question_slug stringlengths 3 77 | title stringlengths 1 183 | slug stringlengths 12 45 | summary stringlengths 1 160 ⌀ | author stringlengths 2 30 | certification stringclasses 2
values | created_at stringdate 2013-10-25 17:32:12 2025-04-12 09:38:24 | updated_at stringdate 2013-10-25 17:32:12 2025-04-12 09:38:24 | hit_count int64 0 10.6M | has_video bool 2
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maximum-number-of-tasks-you-can-assign | C++ greedy + binary search | c-greedy-binary-search-by-robbinb1993-xzef | \nclass Solution {\npublic:\n bool pos(const int M, vector<int>& tasks, vector<int>& workers, int pills, int strength) { \n multiset<int> W;\n | robbinb1993 | NORMAL | 2022-02-20T12:51:15.510738+00:00 | 2022-02-20T12:51:15.510768+00:00 | 341 | false | ```\nclass Solution {\npublic:\n bool pos(const int M, vector<int>& tasks, vector<int>& workers, int pills, int strength) { \n multiset<int> W;\n for (int i = int(workers.size()) - 1; i >= int(workers.size()) - M; i--)\n W.insert(workers[i]);\n \n for (int i = M - 1; i >= 0; i--) {\n auto it = W.lower_bound(tasks[i]);\n if (it == W.end()) {\n if (pills == 0)\n return false;\n it = W.lower_bound(tasks[i] - strength);\n if (it == W.end())\n return false;\n pills--;\n }\n W.erase(it);\n }\n return true; \n }\n \n int maxTaskAssign(vector<int>& tasks, vector<int>& workers, int pills, int strength) {\n sort(tasks.begin(), tasks.end());\n sort(workers.begin(), workers.end());\n int L = 0;\n int R = min(int(tasks.size()), int(workers.size()));\n int ans;\n while (L <= R) {\n int M = (L + R) / 2;\n if (pos(M, tasks, workers, pills, strength)) {\n ans = M;\n L = M + 1; \n }\n else\n R = M - 1;\n }\n return ans;\n }\n};\n``` | 0 | 0 | [] | 0 |
maximum-number-of-tasks-you-can-assign | c++ solution using binary search | c-solution-using-binary-search-by-dilips-nmsb | \nclass Solution {\npublic:\n bool find(vector<int>&t,vector<int>&w,int mid,int pill,int s)\n {\n multiset<int>st(w.begin(),w.end());\n for( | dilipsuthar17 | NORMAL | 2022-01-28T15:23:00.390105+00:00 | 2022-01-28T15:23:00.390143+00:00 | 521 | false | ```\nclass Solution {\npublic:\n bool find(vector<int>&t,vector<int>&w,int mid,int pill,int s)\n {\n multiset<int>st(w.begin(),w.end());\n for(int i=mid-1;i>=0;i--)\n {\n auto it=st.lower_bound(t[i]);\n if(it==st.end())\n {\n it=st.lower_bound(t[i]-s);\n pill--;\n if(it==st.end()||pill<0)\n {\n return false;\n }\n }\n st.erase(it);\n }\n return true;\n }\n int maxTaskAssign(vector<int>& t, vector<int>& w, int pill,int s) \n {\n sort(t.begin(),t.end());\n sort(w.begin(),w.end());\n int n=t.size();\n int m=w.size();\n int l=0;\n int ans=l;\n int r=min(n,m);\n while(l<=r)\n {\n int mid=(l+r)/2;\n if(find(t,w,mid,pill,s))\n {\n ans=mid;\n l=mid+1;\n }\n else\n {\n r=mid-1;\n }\n }\n return ans;\n }\n};\n``` | 0 | 0 | ['C', 'Binary Tree', 'C++'] | 0 |
maximum-number-of-tasks-you-can-assign | C++ | Multiset | Binary Search | c-multiset-binary-search-by-tanishbothra-q279 | \nclass Solution {\npublic:\n int maxTaskAssign(vector<int>& tasks, vector<int>& workers, int pills, int strength) {\n \n sort(begin(tasks),end(tas | tanishbothra22 | NORMAL | 2021-12-27T16:04:42.770372+00:00 | 2021-12-27T16:07:55.273127+00:00 | 390 | false | ```\nclass Solution {\npublic:\n int maxTaskAssign(vector<int>& tasks, vector<int>& workers, int pills, int strength) {\n \n sort(begin(tasks),end(tasks));\n sort(begin(workers),end(workers),greater<int>());\n \n \n int n=tasks.size();\n int m=workers.size();\n \n int low=0;\n int high=n;\n int ans=0;\n \n while(low<=high){\n int mid= low+(high-low)/2;\n int c=0;\n int j=0;\n int k=m-1;\n int p=pills;\n multiset<int,greater<int>>st(begin(workers),begin(workers)+min(mid,m));\n for(int i=mid-1;i>=0;i--){\n if(st.empty())break;\n auto it=st.begin();\n if(*it>=tasks[i]){\n c++;\n st.erase(it);\n }else{\n auto it =st.end();\n it--;\n bool flag=false;\n while(p>0){\n if(*it+strength>=tasks[i]){\n p--;\n flag=true;\n st.erase(it);\n c++;\n break;\n }else{\n if(it==st.begin())break;\n it--;\n }\n }\n \n if(!flag)break;\n }\n }\n\t\tif(c==mid){\n\t\t\tans=mid;\n\t\t\tlow=mid+1;\n\t\t}else{\n\t\t\thigh=mid-1;\n\t\t} \n \n}\n \nreturn ans;\n \n }\n \n};\n``` | 0 | 0 | ['C'] | 0 |
maximum-number-of-tasks-you-can-assign | Why does example 3 return '2' instead of '3' | why-does-example-3-return-2-instead-of-3-f4we | For the 3rd example in the problem description, why does the output expect 2 instead of 3? (0-indexed) Worker 1 can be assigned to task 0, worker 2 can be assig | springathing | NORMAL | 2021-12-16T05:12:08.659775+00:00 | 2021-12-16T05:24:36.100191+00:00 | 102 | false | For the 3rd example in the problem description, why does the output expect 2 instead of 3? (0-indexed) Worker 1 can be assigned to task 0, worker 2 can be assigned to task 1 with 1 pill boost, and worker 3 can be assigned to task 2 with 2 pill boosts.\n```\nInput: tasks = [10,15,30], workers = [0,10,10,10,10], pills = 3, strength = 10\nOutput: 2\n```\n\nHere is my wrong answer code that I believe should give me AC without using Binary Search\n```\npublic class Solution {\n public int MaxTaskAssign(int[] t, int[] w, int p, int s) {\n // Sort both arrays so strongest worker and hardest task are at array.len - 1 position\n Array.Sort(t);\n Array.Sort(w);\n \n int r = 0;\n \n // Find the 1st task that the last worker is able to handle, else iterate down to -1 in the tasks array\n int checkTask = t.Length - 1, checkWorker = w.Length - 1;\n while (checkTask >= 0) {\n if (w[checkWorker] >= t[checkTask]) { // found first task that can be handled without pills\n break;\n }\n checkTask--;\n }\n \n // handle all tasks by workers that don\'t require any pills\n int handleTask = checkTask, handleWorker = checkWorker;\n while (handleTask >= 0 && handleWorker >= 0 && w[handleWorker] >= t[handleTask]) {\n r++;\n handleTask--;\n handleWorker--;\n }\n \n // Starting from the first worker unable to handle any tasks without pills\n int startTask = 0, startWorker = handleWorker; \n while (startTask < t.Length && startWorker >= 0) { \n // Skip the tasks already handled by previous workers\n if (startTask > handleTask && startTask <= checkTask) {\n startTask++;\n continue;\n }\n\n // Apply magic pills until either the worker is strong enough to handle task, \n // or the number of available pills reaches 0\n if (w[startWorker] < t[startTask] && p > 0) { \n while (p > 0 && w[startWorker] < t[startTask]) { \n w[startWorker] += s;\n p--;\n } \n }\n \n // Check to see if the worker is capable of handling the task after any consumption of magic pills\n if (w[startWorker] >= t[startTask]) {\n startTask++;\n r++;\n } \n \n startWorker--;\n }\n \n return r;\n }\n}\n``` | 0 | 0 | [] | 1 |
maximum-number-of-tasks-you-can-assign | C# Solution | c-solution-by-springathing-o9b0 | Binary Search\n\npublic class Solution {\n public int MaxTaskAssign(int[] t, int[] w, int p, int s) {\n Array.Sort(t);\n Array.Sort(w);\n | springathing | NORMAL | 2021-12-16T05:08:25.355572+00:00 | 2021-12-16T05:08:25.355612+00:00 | 129 | false | Binary Search\n```\npublic class Solution {\n public int MaxTaskAssign(int[] t, int[] w, int p, int s) {\n Array.Sort(t);\n Array.Sort(w);\n \n int l = 0, r = Math.Min(t.Length, w.Length);\n while (l + 1 < r) {\n int m = l + (r - l) / 2;\n if (CanAssign(t, w, p, s, m)) {\n l = m;\n } else {\n r = m;\n }\n }\n \n if (CanAssign(t, w, p, s, r)) return r;\n else return l;\n }\n \n public bool CanAssign(int[] t, int[] w, int p, int s, int cnt) {\n List<int> dq = new List<int>();\n int end = w.Length - 1;\n for (int i = cnt - 1; i >= 0; --i) {\n while (end >= w.Length - cnt && w[end] + s >= t[i]) {\n dq.Add(w[end]);\n end--;\n }\n \n if (dq.Count == 0) return false;\n \n if (dq[0] >= t[i]) {\n dq.RemoveAt(0);\n } else {\n dq.RemoveAt(dq.Count - 1);\n p--;\n if (p < 0) return false;\n }\n }\n \n return true;\n }\n}\n``` | 0 | 0 | [] | 0 |
maximum-number-of-tasks-you-can-assign | Python 3 solution | python-3-solution-by-dhananjay79-6hao | After watching striver\'s live coding, I understood the intution behind solving this problem.\nI am dumb :|\n\nclass Solution:\n def maxTaskAssign(self, T: | dhananjay79 | NORMAL | 2021-12-09T20:42:15.053039+00:00 | 2021-12-09T20:42:15.053082+00:00 | 220 | false | After watching striver\'s live coding, I understood the intution behind solving this problem.\nI am dumb :|\n```\nclass Solution:\n def maxTaskAssign(self, T: List[int], W: List[int], pills: int, strength: int) -> int:\n \n \n def isPossible(T,W,pills,strength):\n\n harderTask, strongestMan = len(T) - 1, -1\n \n for _ in range(len(T)):\n if W[strongestMan] >= T[harderTask]:\n W.pop()\n else:\n if not pills: return False\n power_needed = T[harderTask] - strength\n index = bisect.bisect_left(W,power_needed)\n if index >= len(W): return False\n pills -= 1\n W.pop(index)\n harderTask -= 1\n \n return True\n \n \n \n T.sort()\n W.sort()\n \n l,h, = 0, min(len(T),len(W))\n \n while l <= h:\n mid = (l+h) // 2\n\n res = isPossible(T[:mid], W[len(W)-mid:], pills, strength) \n \n if res: l = mid + 1\n else: h = mid - 1\n \n return h\n \n``` | 0 | 0 | [] | 0 |
maximum-number-of-tasks-you-can-assign | Same multiset solution but a bit different approach gets WA | same-multiset-solution-but-a-bit-differe-cswf | My solution a bit different but do not know why it doesn\'t work. \n\n1) Start from hardest task. \n2) Find weakest worker that can do the task without pill\n3) | tahlil | NORMAL | 2021-11-20T03:42:27.495453+00:00 | 2021-11-20T03:53:24.448332+00:00 | 239 | false | My solution a bit different but do not know why it doesn\'t work. \n\n1) Start from hardest task. \n2) Find weakest worker that can do the task without pill\n3) If step 2 fails then find the weakest worker with pill can do it.\n4) If succeeds then remove the worker. Otherwise try the next task.\n\n```\nclass Solution {\npublic:\n int maxTaskAssign(vector<int>& tasks, vector<int>& workers, int pills, int strength) \n {\n sort(tasks.rbegin(),tasks.rend());//Sorting tasks hardest to easiest\n \n multiset<int>w(workers.begin(),workers.end());\n \n int ans = 0;\n for(int i=0);i<tasks.size() && w.size()>0;i++)\n {\n int task = tasks[i];\n int pillUsed = 0;\n \n auto pos = w.lower_bound(task); // Finding the weakest worker that can do it.\n if(pos == w.end() && pills)\n pos = w.lower_bound(task-strength),pillUsed=1; // Finding the weakest workder with pill that can do it.\n \n if(pos != w.end()) // Means found one worker that can do the task\n {\n ans++;\n w.erase(pos); // removing the worker\n pills-=pillUsed; // Decreasing pill count\n }\n \n }\n return ans;\n }\n};```\n \n WA on the following case which is too large to debug. \n [7908,9988,9571,5279,4047,9760,3274,7098,6367,4774,9975,5544,8811,2564,3835,6634,5648,9052,8143,5502,1285,7300,5630,7578,6522,2243,7284,6534,3766,1835,4153,4333,6338,6373,7517,6930,8190,2834,2218,2945,6929,4170,9254,9312,9789,1324,3851,4038,9497,6486,7949,5781,7787,5185,2726,8538,3698,6929,2613,6860,6981,7506,5294,6213,9848,4539,1234,8108,3832,5068,2712,6301,8340,7950,1320,9111,5411,8075,9752,6882,9679,9463,6580,9986,5114,4483,7816,1878,2204,4364,1603,3131,3492,8579,3026,2521,5679,8630,8667,3827,1555,3296,1118,4644,4866,1312,7632,9550,6914,9195,1009,2145,5184,4996,2913,6914,3584,4866,8505,7708,1309,2780,1794,6103,6161,9576,9885,1843,2180,9261,6516,7411,8606,4633,5653,8562,9533,8516,2503,3270,5264,1737,1603,1376,1834,6990,8234,8975,4194,2276,7633,3401,3521,6003,7685,2139,9061,2786,8637,7517,1411,3732,9200,9772,8017,4008,9189,4728,5141,8600,5512,4239,5236,6909,9942,4712,7017,9755,2365,3130,4668,9101,1414,7787,4533,7845,3755,2534,7896,4710,7581,2301,5079,4236,7276,8656,4777,1857]\n[4612,4669,4273,1929,1925,1342,4565,2152,1909,4897,2697,1419,1998,4789,2940,3388,4619,1427,1798,917,2270,1639,1633,4669,2674,2348,3714,3909,4359,3151,1639,4533,3444,3531,887,528,2346,1481,831,2345,3610,4507,2890,4740,3959,648,1468,3063,2416,4091,1151,2196,999,2708,578,978,4113,4229,2052,2154,2149,583,1029,2020,4498,4638,4932,2986,2749,1047,2434,971,1645,570,1395,3603,4581,3607,3158,2758,1046,1171,2204,1421,3708,4769,3399,981,3396,4837,3633,4067,4141,2037,1622,2257,1529,1371,4090,3273,4767,3543,1098,503,3905,4427,3875,2594,4878,2252,912,4838,509,2989,3304,4268,1520,4027,3691,993,600,3529,3762,1854,592,1579,2191,3051,1897,4050,1345,3416,1108,4862,4587,3065,3486,2138,1272,4237,4235,4107,1951,3747,2774,4944,3815,2560,3688,1838,2821,3098,1361,1439,2486,4599,2215,1908,2432,1862,1780,1143,4117,3175,3839,3019,4576,4343,4186,1643,3472,1637,693,4128,4709,4500,2639,4022,2886,1708,2721,4686,4870,772,557,1845,2788,821,3752]\n35\n2208\nOutput:\n113\nExpected:\n118\n | 0 | 0 | [] | 1 |
maximum-number-of-tasks-you-can-assign | [Golang] Can somebody help me to point out why my solution fails at test cases 33? | golang-can-somebody-help-me-to-point-out-yebz | My logic: Do binary search to choose the potential answer k. \n\n1) choose the smallest k tasks and strongest k workers. try to assign it without pill first (fi | shentianjie466357304 | NORMAL | 2021-11-20T03:42:00.055901+00:00 | 2021-11-20T03:45:35.829179+00:00 | 103 | false | My logic: Do binary search to choose the potential answer k. \n\n1) choose the smallest k tasks and strongest k workers. try to assign it without pill first (find the weakest worker possible greedy strategy)\n2) If not try to find the weakest worker with a pill \n3) Otherwise it is impossible to assign k tasks, return false. \n\n\nIt fails at test cases 33: \n```\n[1943,2068,4077,7832,8061,6939,6263,8917,8008,5348,8837,4753,4607,7638,9000,7222,4552,1123,9225,6896,4154,6303,3186,2325,9994,5855,8851,7377,1930,1187,5094,2689,8852,1507,1567,9575,1193,1557,8840,9075,5032,3642,6917,7968,5310,2315,7516,4776,3091,7027,1788,2007,2651,6112,4264,5644,3585,9408,7410,9605,8151,1538,6905,6759,4518,3444,5036,1589,3902,3037,1468,9179,3000,5339,6805,7394,9418,9262,2888,4708,3402,5554,8714,7393,2848,5946,9808,4301,6675,8564,6300,4359,9506,1946,9673,7412,1164,2986,2198,5144,3763,4782,8835,6994,8035,3332,2342,5243,3150,9084,6519,9798,7682,9919,7473,7686,9978,8092,9897,3985,9874,5842,9740,2145,2426,7069,8963,9250,4142,9434,1895,6559,3233,8431,6278,6748,7305,4359,2144,8009,4890,6486,7464,8645,1704,5915,9586,1394,7504,2124,3150,2051,5026,7612,3715,5757,4355,6394,3202,2777,3949,2349,7398,3029,3081,5116,5078,8048,9934,4348,8518,5201,1203,7935,5006,6388,8680,3427,6048,1957,4026,4618,4080]\n[875,2347,939,3664,3926,4555,1947,4406,4601,3502,4964,1307,4232,2968,4572,3139,2788,1847,1208,2019,4184,1664,1747,3690,4333,891,686,1959,2218,4972,806,741,1490,4529,2909,925,2040,1234,1264,1135,3640,1455,2933,3699,2856,3074,4579,2458,2090,833,4140,4534,2336,4363,1948,4546,4155,3735,3577,2780,4874,1747,4844,3482,3053,3534,549,4500,2237,2128,1554,3210,4161,2211,950,3732,2182,1148,4368,4050,1452,1015,3192,4318,3908,2590,1103,2811,2821,690,2718,3360,2659,3315,579,3108,2979,3903,4367,1906,4964,889,4803,825,2270,4794,4825,4485,4461,1639,3857,1330,3169,2425,3694,1980,2268,3002,2177,3225,2499,2517,1916,2844,760,2167,1786,3179,3222,1432,3775,4747,1764,690,3223,4684,890,2701,1045,3034,1381,1011,2150,4798,2247,1334,3058,934,2895,1484,2784,3341,4412,1748,625,2610,3488,4810,669,4275,4929,1014,2104,3111]\n122\n3131\n```\n\nExpected Output 143 and my output 145\n\n\n\tfunc maxTaskAssign(tasks []int, workers []int, pills int, strength int) int {\n\t\tsort.Ints(tasks)\n\t\tsort.Ints(workers)\n\n\t\th := int(math.Min(float64(len(tasks)), float64(len(workers))))\n\t\tl := 0\n\t\tans := 0\n\t\tfor l <= h {\n\t\t\tm := l + (h - l) / 2\n\t\t\tif canDo(tasks[0:m], workers[len(workers)-m:], pills, strength) {\n\t\t\t\tans = m\n\t\t\t\tl = m + 1\n\t\t\t} else {\n\t\t\t\th = m - 1\n\t\t\t}\n\t\t}\n\t\treturn ans\n\t}\n\n\tfunc canDo(tasks, workers []int, pills, strength int) bool {\n\t\tfor j := len(tasks) - 1; j >= 0; j-- {\n\t\t\t// biggest task\n\t\t\ttask := tasks[j]\n\t\t\tidx := findPlace(workers, task)\n\t\t\tflag := false\n\t\t\tif idx >= 0 {\n\t\t\t\tworkers = append(workers[0:idx], workers[idx+1:]...)\n\t\t\t\tflag = true\n\t\t\t} else if idx = findPlace(workers, task - strength); idx >= 0 && pills > 0 {\n\t\t\t\tpills--\n\t\t\t\tworkers = append(workers[0:idx], workers[idx+1:]...)\n\t\t\t\tflag = true\n\t\t\t}\n\n\t\t\tif !flag {\n\t\t\t\treturn false\n\t\t\t}\n\t\t}\n\t\treturn len(workers) == 0\n\t}\n\n\tfunc findPlace(workers []int, task int) int {\n\t\t// find the leftmost worker that can accomplish the task\n\t\tl := 0\n\t\tr := len(workers) - 1\n\t\tans := -1\n\t\tfor l <= r {\n\t\t\tm := l + (r - l) / 2\n\t\t\tif workers[m] >= task {\n\t\t\t\tans = m\n\t\t\t\tr = m - 1\n\t\t\t} else {\n\t\t\t\tl = m + 1\n\t\t\t}\n\t\t}\n\t\treturn ans\n\t} | 0 | 0 | [] | 0 |
maximum-number-of-tasks-you-can-assign | Scala, use a TreeMap for greedy algorithm when validating on the binary search | scala-use-a-treemap-for-greedy-algorithm-1pdv | scala\n\n def maxTaskAssign(tasks: Array[Int], workers: Array[Int], pills: Int, strength: Int): Int = {\n type int = Int\n var res = 0\n tasks.sortInP | qiuqiushasha | NORMAL | 2021-11-18T19:10:35.769002+00:00 | 2021-11-18T19:10:35.769029+00:00 | 65 | false | ```scala\n\n def maxTaskAssign(tasks: Array[Int], workers: Array[Int], pills: Int, strength: Int): Int = {\n type int = Int\n var res = 0\n tasks.sortInPlaceWith((a, b) => a <= b)\n workers.sortInPlaceWith((a, b) => a <= b)\n\n import scala.collection.mutable.TreeMap\n\n val tl = tasks.length\n val wl = workers.length\n\n def f(target: int): Boolean = {\n\n var taken = 0\n var j = wl - 1\n val tm = new TreeMap[int, int]()((a, b) => Integer.compare(a, b))\n\n (target - 1 to 0 by -1).foreach(i => {\n\n val ct = tasks(i)\n while (j >= 0 && workers(j) >= ct) {\n tm.put(workers(j), tm.getOrElse(workers(j), 0) + 1)\n j -= 1\n }\n val weakest = tm.minAfter(ct)\n if (weakest.isDefined) {\n val key = weakest.get._1\n tm.put(key, tm(key) - 1)\n if (tm(key) == 0) tm -= key\n } else {\n if (taken < pills) {\n while (j >= 0 && workers(j) + strength >= ct) {\n tm.put(workers(j), tm.getOrElse(workers(j), 0) + 1)\n j -= 1\n }\n val weakestPill = tm.minAfter(ct - strength)\n if (weakestPill.isDefined) {\n val key = weakestPill.get._1\n tm.put(key, tm(key) - 1)\n if (tm(key) == 0) tm -= key\n taken += 1\n\n } else {\n return false\n }\n\n } else {\n return false\n }\n\n }\n\n })\n\n true\n }\n\n var s = 0\n var e = Math.min(tl, wl)\n while (s <= e) {\n var mid = s + (e - s) / 2\n if (f(mid)) {\n res = Math.max(res, mid)\n s = mid + 1\n } else {\n e = mid - 1\n }\n\n }\n\n res\n\n }\n``` | 0 | 0 | [] | 0 |
maximum-number-of-tasks-you-can-assign | Rust binary search + BTreeMap | rust-binary-search-btreemap-by-robetking-6cnd | Would be nice to have a multiset in rust but can use BTreeMap with counts.\n\nIdea to check if it\'s possible in a binary search iteration: take the K smallest | robetkingnz | NORMAL | 2021-11-14T16:36:39.463116+00:00 | 2021-11-14T16:39:13.856870+00:00 | 315 | false | Would be nice to have a multiset in rust but can use BTreeMap with counts.\n\nIdea to check if it\'s possible in a binary search iteration: take the K smallest tasks and the K strongest workers. Go through the workers left to right assigning the weakest worker to the easiest task. If the worker can\'t do the easiest task, give the worker a pill and take the hardest task the worker can do. If we ever get a worker that can\'t take a task (out of pills or pills not strong enough), it\'s not possible.\n\n```\n// @robertkingnz\nfn possible(tasks: &[i32], workers: &[i32], mut pills: i32, strength: i32) -> bool {\n let mut m: BTreeMap<i32, i32> = BTreeMap::new();\n for &t in tasks {\n let e = m.entry(t).or_insert(0);\n *e += 1;\n }\n for &w in workers {\n let (&first, &first_count) = m.iter().next().unwrap();\n if w >= first {\n if first_count == 1 {\n m.remove(&first);\n } else {\n m.insert(first, first_count - 1);\n }\n } else if pills == 0 {\n return false;\n } else if let Some((&x, &x_count)) = m.range(..=(w+strength)).next_back() {\n pills -= 1;\n if x_count == 1 {\n m.remove(&x);\n } else {\n m.insert(x, x_count - 1);\n }\n } else {\n return false;\n }\n }\n true\n}\n\nimpl Solution {\n pub fn max_task_assign(mut tasks: Vec<i32>, mut workers: Vec<i32>, pills: i32, strength: i32) -> i32 {\n tasks.sort();\n workers.sort();\n let n = tasks.len().min(workers.len());\n tasks.drain(n..tasks.len());\n workers.drain(..(workers.len()-n));\n let mut a = 0;\n let mut b = n+1;\n while a < b {\n let i = a + (b-a)/2;\n let ok = possible(\n &tasks[..i],\n &workers[n-i..],\n pills,\n strength);\n if ok {\n a = i+1;\n } else {\n b = i;\n }\n }\n if a > 0 {\n return (a-1) as i32;\n }\n 0\n }\n}\n``` | 0 | 0 | [] | 0 |
maximum-number-of-tasks-you-can-assign | Easy C++ Solution| Binary Search | MultiSet | easy-c-solution-binary-search-multiset-b-uldz | {Based on solution by @astroash}\nWe first do binary search on the solution space, i.e, 0 to minimum of tasks.size or workers.size().\n\nThe condition we check | harit_1 | NORMAL | 2021-11-14T08:18:19.162272+00:00 | 2021-11-14T08:19:48.434542+00:00 | 217 | false | *{Based on solution by @astroash}*\nWe first do binary search on the solution space, i.e, 0 to minimum of tasks.size or workers.size().\n\nThe condition we check in iteration is it possible to assign the first k smallest tasks to the workers?\n\nFor each task, there can be three cases:\n- A worker without the pill can complete it.\n- A worker with the pill can complete it.\n- No available worker, with or without the pill can complete it.\n\nThis is further explained as comments in the code.\n\nPlease upvote. :)\n\n\n\n```\nclass Solution {\n \n bool possible(vector<int>& tasks, vector<int>& workers, int t, int strength, int mid){\n multiset<int> myset(workers.begin(), workers.end());\n multiset<int>::iterator it;\n \n for(int i=mid-1;i>=0;i--){\n it = myset.end();\n it--;\n if(*it>=tasks[i]){ // we check if a worker without the pill can complete it. Here, we should check for the strongest worker for this task.\n myset.erase(it);\n }\n else { // If worker without the pill can\'t complete it, we check for the weakest worker if he/she can complete the task with the help of pill. I also track the number of pills available and reduce the count if used.\n it = myset.lower_bound(tasks[i]-strength);\n if(t>0 && it!=myset.end()){\n t--;\n myset.erase(it);\n }\n else{ // If above two conditions aren\'t fulfilled, then these mid samllest no. of tasks can\'t be assigned.\n return false;\n } \n }\n }\n \n return true;\n }\n \npublic:\n int maxTaskAssign(vector<int>& tasks, vector<int>& workers, int pills, int strength) {\n int n = tasks.size();\n int m = workers.size();\n sort(tasks.begin(), tasks.end());\n sort(workers.begin(), workers.end());\n \n int l=0, r=min(n,m);\n int ans=0;\n while(l<=r){\n int mid = l+(r-l)/2;\n if(possible(tasks, workers, pills, strength, mid)){\n ans=mid;\n l=mid+1;\n }\n else{\n r=mid-1;\n }\n }\n \n return ans;\n }\n};\n``` | 0 | 0 | ['Binary Search', 'C'] | 0 |
maximum-number-of-tasks-you-can-assign | c++ nlg^2n | c-nlg2n-by-colinyoyo26-39cs | \nclass Solution {\npublic:\n int maxTaskAssign(vector<int>& tasks, vector<int>& ws, int ps, int st) {\n sort(tasks.begin(), tasks.end());\n so | colinyoyo26 | NORMAL | 2021-11-14T01:10:48.240610+00:00 | 2021-11-14T01:10:48.240659+00:00 | 157 | false | ```\nclass Solution {\npublic:\n int maxTaskAssign(vector<int>& tasks, vector<int>& ws, int ps, int st) {\n sort(tasks.begin(), tasks.end());\n sort(ws.begin(), ws.end(), greater<int>());\n int m = tasks.size(), n = ws.size();\n auto isvalid = [&] (int k) {\n if (k > min(m, n)) return false;\n int p = ps;\n multiset<int> ms(ws.begin(), ws.begin() + k);\n for (int j = k - 1; j >= 0; j--) {\n auto it = prev(ms.end());\n if (*it < tasks[j]) {\n it = ms.lower_bound(tasks[j] - st);\n if (it == ms.end() || !p--) return false;\n }\n ms.erase(it);\n }\n return true;\n };\n int l = 1 << 20, ans = 0;\n for (; l; l >>= 1)\n if (isvalid(l | ans)) ans |= l;\n return ans;\n }\n};\n``` | 0 | 1 | [] | 0 |
fizz-buzz-multithreaded | Java, using synchronized with short explanation. | java-using-synchronized-with-short-expla-dyp1 | [Code is at the end]\n\nSo I just keep a shared currentNumber showing where we\'re up to. Each thread has to then check whether or not it should take its turn. | hai_dee | NORMAL | 2019-09-19T04:08:01.108833+00:00 | 2019-09-19T04:08:01.108871+00:00 | 19,022 | false | [Code is at the end]\n\nSo I just keep a shared ```currentNumber``` showing where we\'re up to. Each thread has to then check whether or not it should take its turn. If it\'s not the current thread\'s turn, it calls ```wait()```, thus suspending and giving up the monitor. After each increment of ```currentNumber```, we need to call ```notifyAll()``` so that the other threads are woken and can re-check the condition. They will all be given a chance to run \n\nThe implicit locks, (aka monitors) provided by synchronized can be a bit confusing at first to understand, so I recommend reading up on them if you are confused. I personally found these sites useful:\n+ https://docs.oracle.com/javase/tutorial/essential/concurrency/index.html\n+ https://howtodoinjava.com/java/multi-threading/java-synchronized/\n\nYou might notice something slightly unusual in my wait code, i.e.\n\n```\nif (currentNumber % 3 != 0 || currentNumber % 5 == 0) {\n wait();\n continue;\n}\n```\n\nWhen perhaps you would have expected the more traditional form of:\n```\nwhile (currentNumber % 3 != 0 || currentNumber % 5 == 0) {\n wait();\n}\n```\n\nSeeing as we are always told that waiting conditions must be a loop, right? (Because sometimes it will have to wait more than once for its turn). The reason I have done this though is because otherwise there\'d have to be an additional check in the waiting loop for if the currentNumber value is still below n.\n```\nwhile (currentNumber % 3 != 0 || currentNumber % 5 == 0) {\n wait();\n\t if (currentNumber > n) return;\n}\n```\n\nWhile this does work, I felt it was probably the more convoluted option. But it\'s definitely an option, and I\'d be interested to hear thoughts on this "design" decision. In effect, it is a wait in a loop, it\'s just that it utilises the outer loop\'s condition (by using continue).\n\nI probably could pull some of the repetition into a seperate method. One challenge was that 3 of the methods took a Runnable, and one took an IntConsumer.\n\n```\nclass FizzBuzz {\n \n private int n;\n private int currentNumber = 1;\n \n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public synchronized void fizz(Runnable printFizz) throws InterruptedException {\n while (currentNumber <= n) {\n if (currentNumber % 3 != 0 || currentNumber % 5 == 0) {\n wait();\n continue;\n }\n printFizz.run();\n currentNumber += 1;\n notifyAll();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public synchronized void buzz(Runnable printBuzz) throws InterruptedException {\n while (currentNumber <= n) {\n if (currentNumber % 5 != 0 || currentNumber % 3 == 0) {\n wait();\n continue;\n }\n printBuzz.run();\n currentNumber += 1;\n notifyAll();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public synchronized void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (currentNumber <= n) {\n if (currentNumber % 15 != 0) {\n wait();\n continue;\n }\n printFizzBuzz.run();\n currentNumber += 1;\n notifyAll();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public synchronized void number(IntConsumer printNumber) throws InterruptedException {\n while (currentNumber <= n) {\n if (currentNumber % 3 == 0 || currentNumber % 5 == 0) {\n wait();\n continue;\n }\n printNumber.accept(currentNumber);\n currentNumber += 1;\n notifyAll();\n }\n }\n``` | 126 | 2 | [] | 12 |
fizz-buzz-multithreaded | python, >99.28%, a standard Lock() based solution, with detailed explanation | python-9928-a-standard-lock-based-soluti-0ph0 | \nimport threading\n\nclass FizzBuzz:\n def __init__(self, n: int): \n self.n = n\n self.f = threading.Lock()\n self.b = threading. | rmoskalenko | NORMAL | 2020-03-18T01:27:11.901818+00:00 | 2020-08-28T03:40:10.206829+00:00 | 8,136 | false | ```\nimport threading\n\nclass FizzBuzz:\n def __init__(self, n: int): \n self.n = n\n self.f = threading.Lock()\n self.b = threading.Lock()\n self.fb = threading.Lock()\n self.f.acquire()\n self.b.acquire()\n self.fb.acquire()\n self.main = threading.Lock()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n while True:\n self.f.acquire()\n if self.n == 0 :\n return\n printFizz()\n self.main.release()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n while True:\n self.b.acquire()\n if self.n == 0:\n return\n printBuzz()\n self.main.release()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n while True:\n self.fb.acquire()\n if self.n == 0:\n return\n printFizzBuzz()\n self.main.release()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for i in range(1, self.n+1):\n #print("number:",i)\n self.main.acquire()\n if i % 15 == 0:\n self.fb.release()\n elif i % 3 == 0:\n self.f.release()\n elif i % 5 == 0:\n self.b.release()\n else:\n printNumber(i)\n self.main.release()\n\n self.main.acquire() \n self.n = 0\n self.f.release()\n self.b.release()\n self.fb.release()\n return\n\n```\n\nSome background first. Python gives us a tool called Lock(). It\'s basically a flag and it can be either acquired or released. So an acquire() call will wait until Lock is released. Originally locks are created as released. So all we need here is Lock() to create a lock and two methods: acquire() and release().\n\nThis is very similar to Semaphore(), but semaphores are deprecated and going to be removed, so let\'s stick with Locks.\n\nOk, now we are familiar with the special tools, let\'s think about the app logic.\n\nWe have 4 threads. 3 of them (Fizz, Buzz and FizzBuzz) are more specialized and they print only very specific numbers, the fourth one (number) is used more frequently, so we can use it as an orchestrator or "main" thread.\n\nSo on a high level, the number thread is going to acquier its own lock, then it will check the current number, if it\'s %15, %3 or %5 - it\'s going to release a corresponding lock, otherwise it\'s going to print the number itself and release its own lock.\n\nThe other 3 threads will be spinning in loops waiting for their lock to be acquired, then they print the current number (during that time the number thread is locked), then they release the main lock.\n\nOkey, good, we\'ve got the main framework figured out, now we need to add the details.\n\nFirst of all, when the class is initialized, we want only the main thread to be released, the other three threads should stay locked. We are going to do it by:\n```\n self.f.acquire()\n self.b.acquire()\n self.fb.acquire()\n```\n\nAt this point we can get our program started. Now we need to think how to stop it nicely.\n\nThe number thread has a `for` loop, so it will spin exactly as many cycles as needed and it will finish. But how can we terminate the other 3?\n\nThere could be a few ways.\n\n1. Use some global variable to tell all threads to stop or continue. For example, we can set self.n to 0 once we are done and in all three threads check if `self.n != 0`. Another way would be to use a dedicated flag ( in this example it is `self.done`).\n2. Let every thread count how many cycles it needs to execute. Basically instead of having `while True ... if flag is set then break` we can say `for c in range(self.n // 15)` . An example of such code is below:\n\n```\nimport threading\n\nclass FizzBuzz:\n def __init__(self, n):\n self.n = n\n self.f = threading.Lock()\n self.b = threading.Lock()\n self.fb = threading.Lock()\n self.main = threading.Lock() \n self.f.acquire()\n self.b.acquire()\n self.fb.acquire()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz):\n for i in range (self.n // 3 - self.n // 15):\n self.f.acquire()\n printFizz()\n self.main.release()\n \n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz):\n for i in range (self.n // 5 - self.n // 15):\n self.b.acquire()\n printBuzz()\n self.main.release()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz):\n for i in range (self.n // 15):\n self.fb.acquire()\n printFizzBuzz()\n self.main.release() \n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber):\n for i in range(1, self.n + 1): \n self.main.acquire() \n if i % 15 == 0:\n self.fb.release()\n elif i % 3 == 0:\n self.f.release()\n elif i % 5 == 0:\n self.b.release()\n else:\n printNumber(i)\n self.main.release() \n```\n\nSo what is the difference between 2 approaches?\n\nPerformance wise, they are very comparable, both showing results in high 90% range. \nThe second approach produces a noticably shorter code. \n\nBut there is a more philosophical difference.\n\nThe global flag approach keeps one thread as a master where all logic is implemented while the other three threads are dumb workers. They repeat exactly same step until they are told to stop. The other approach has logic spread between all 4 threads. So while workers are becoming more sophisticated, they are also more independent and they require fewer communication channels.\n\nGenerally speaking, on a very large scale the second approach has advantages. Every communication between the threads can become a bottleneck, so the more independent threads the better (just imagine that you\'re running it on some super broad cluster. Syncing the state of every shared resource comes with a price, so Lock vs Lock+GlobaFlag can make a difference).\n\nBut on a small scale, keeping most of the logic in one place has some advantages too. \n | 70 | 1 | [] | 10 |
fizz-buzz-multithreaded | Java implementation using Semaphore as token 4ms | java-implementation-using-semaphore-as-t-t6xs | \n\nclass FizzBuzz {\n private int n;\n\tprivate Semaphore fizz = new Semaphore(0);\n\tprivate Semaphore buzz = new Semaphore(0);\n\tprivate Semaphore fizzbu | franklee9527 | NORMAL | 2019-10-08T06:45:44.867795+00:00 | 2019-10-08T06:45:44.867831+00:00 | 6,127 | false | \n```\nclass FizzBuzz {\n private int n;\n\tprivate Semaphore fizz = new Semaphore(0);\n\tprivate Semaphore buzz = new Semaphore(0);\n\tprivate Semaphore fizzbuzz = new Semaphore(0);\n\tprivate Semaphore num = new Semaphore(1);\n\n\tpublic FizzBuzz(int n) {\n this.n = n;\n }\n\n\t// printFizz.run() outputs "fizz".\n\tpublic void fizz(Runnable printFizz) throws InterruptedException {\n\t\tfor (int k = 1; k <= n; k++) {\n\t\t\tif (k % 3 == 0 && k % 5 != 0) {\n\t\t\t\tfizz.acquire();\n\t\t\t\tprintFizz.run();\n\t\t\t\treleaseLock(k + 1);\n\t\t\t}\n\t\t}\n\t}\n\n\t// printBuzz.run() outputs "buzz".\n\tpublic void buzz(Runnable printBuzz) throws InterruptedException {\n\t\tfor (int k = 1; k <= n; k++) {\n\t\t\tif (k % 5 == 0 && k % 3 != 0) {\n\t\t\t\tbuzz.acquire();\n\t\t\t\tprintBuzz.run();\n\t\t\t\treleaseLock(k + 1);\n\t\t\t}\n\t\t}\n\t}\n\n\t// printFizzBuzz.run() outputs "fizzbuzz".\n\tpublic void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n\t\tfor (int k = 1; k <= n; k++) {\n\t\t\tif (k % 15 == 0) {\n\t\t\t\tfizzbuzz.acquire();\n\t\t\t\tprintFizzBuzz.run();\n\t\t\t\treleaseLock(k + 1);\n\t\t\t}\n\t\t}\n\t}\n\n\t// printNumber.accept(x) outputs "x", where x is an integer.\n\tpublic void number(IntConsumer printNumber) throws InterruptedException {\n\t\tfor (int k = 1; k <= n; k++) {\n\t\t\tif (k % 3 != 0 && k % 5 != 0) {\n\t\t\t\tnum.acquire();\n\t\t\t\tprintNumber.accept(k);\n\t\t\t\treleaseLock(k + 1);\n\t\t\t}\n\t\t}\n\t}\n\n\tpublic void releaseLock(int n) {\n\t\tif (n % 3 == 0 && n % 5 != 0) {\n\t\t\tfizz.release();\n\t\t} else if (n % 5 == 0 && n % 3 != 0) {\n\t\t\tbuzz.release();\n\t\t} else if (n % 15 == 0) {\n\t\t\tfizzbuzz.release();\n\t\t} else {\n\t\t\tnum.release();\n\t\t}\n\t}\n}\n``` | 69 | 0 | [] | 10 |
fizz-buzz-multithreaded | C++ mutex / condition_variable, please suggest improvements | c-mutex-condition_variable-please-sugges-w5p0 | ```\nprivate:\n int n;\n int count;\n mutex m;\n condition_variable cv;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n this->count | grokus | NORMAL | 2019-09-22T16:10:36.308025+00:00 | 2019-09-22T16:10:36.308063+00:00 | 8,977 | false | ```\nprivate:\n int n;\n int count;\n mutex m;\n condition_variable cv;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n this->count = 1;\n }\n\n void fizz(function<void()> printFizz) {\n while (true) {\n unique_lock<mutex> lock(m);\n while (count <= n && (count % 3 != 0 || count % 5 == 0))\n cv.wait(lock);\n if (count > n) return;\n printFizz();\n ++count;\n cv.notify_all();\n }\n }\n\n void buzz(function<void()> printBuzz) {\n while (true) {\n unique_lock<mutex> lock(m);\n while (count <= n && (count % 5 != 0 || count % 3 == 0))\n cv.wait(lock);\n if (count > n) return;\n printBuzz();\n ++count;\n cv.notify_all();\n }\n }\n\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while (true) {\n unique_lock<mutex> lock(m);\n while (count <= n && (count % 5 != 0 || count % 3 != 0))\n cv.wait(lock);\n if (count > n) return;\n printFizzBuzz();\n ++count;\n cv.notify_all();\n }\n }\n\n void number(function<void(int)> printNumber) {\n while (true) {\n unique_lock<mutex> lock(m);\n while (count <= n && (count % 5 == 0 || count % 3 == 0))\n cv.wait(lock);\n if (count > n) return;\n printNumber(count++);\n cv.notify_all();\n }\n } | 48 | 1 | [] | 15 |
fizz-buzz-multithreaded | Python 3 non-cheesy solution with semaphores | python-3-non-cheesy-solution-with-semaph-p138 | My solution is similar to other Semaphore solutions, but it doesn\'t need math formulas to calculate how many times we should print fizz or buzz.\nI feel that i | ilgor | NORMAL | 2020-01-08T02:32:03.195872+00:00 | 2020-01-08T02:32:03.195921+00:00 | 6,126 | false | My solution is similar to other Semaphore solutions, but it doesn\'t need math formulas to calculate how many times we should print fizz or buzz.\nI feel that it\'s a code smell and not true to the spirit of multi-threading.\nInstead I used **done** flag which is set by controlling thread and allows slave threads to peacefully finish on time without some extra inherent knowledge about the task.\n\nHope you\'ll like it.\n\n```\n# IDEA: use four semaphores with only number one starting unlocked, number-thread will loop numbers and distribute work\n# to other threads with releases, number-thread will set done flag when its loop finishes and other threads will break on this flag\n#\nclass FizzBuzz:\n def __init__(self, n: int):\n self.done = False \n self.n = n\n self.fSem = threading.Semaphore(0)\n self.bSem = threading.Semaphore(0)\n self.fbSem = threading.Semaphore(0)\n self.nSem = threading.Semaphore(1)\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n while True:\n self.fSem.acquire()\n if self.done: break\n printFizz()\n self.nSem.release()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n while True:\n self.bSem.acquire()\n if self.done: break\n printBuzz()\n self.nSem.release()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n while True:\n self.fbSem.acquire()\n if self.done: break\n printFizzBuzz()\n self.nSem.release()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for i in range(1, self.n+1):\n self.nSem.acquire()\n if i % 15 == 0:\n self.fbSem.release()\n elif i % 3 == 0:\n self.fSem.release()\n elif i % 5 == 0:\n self.bSem.release()\n else:\n printNumber(i)\n self.nSem.release()\n self.nSem.acquire() # needed so this thread waits to set done flag only when other threads are done with printing\n self.done = True\n self.fSem.release() # let all other threads to break and finish\n self.bSem.release() #\n self.fbSem.release() #\n``` | 37 | 0 | ['Python', 'Python3'] | 7 |
fizz-buzz-multithreaded | C++ condition_variable waiting on predicate | c-condition_variable-waiting-on-predicat-sm1t | \nclass\xA0FizzBuzz\xA0{\n\xA0\xA0\xA0\xA0private:\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0int\xA0n;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0atomic<int>\xA0current;\n\xA0\xA0 | igorb | NORMAL | 2020-01-20T00:09:24.602439+00:00 | 2020-01-20T00:09:24.602494+00:00 | 3,139 | false | ```\nclass\xA0FizzBuzz\xA0{\n\xA0\xA0\xA0\xA0private:\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0int\xA0n;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0atomic<int>\xA0current;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0mutex\xA0mx;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0condition_variable\xA0cv;\n\xA0\xA0\xA0\xA0public:\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0FizzBuzz(int\xA0n)\xA0{\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0this->n\xA0=\xA0n;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0current\xA0=\xA01;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0}\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0//\xA0printFizz()\xA0outputs\xA0"fizz".\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0void\xA0fizz(function<void()>\xA0printFizz)\xA0\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0{\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0do_work([&](int\xA0i){printFizz();},\xA0[&]{return\xA0(current\xA0%\xA03\xA0==\xA00\xA0&&\xA0current\xA0%\xA05\xA0!=\xA00);});\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0}\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0//\xA0printBuzz()\xA0outputs\xA0"buzz".\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0void\xA0buzz(function<void()>\xA0printBuzz)\xA0\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0{\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0do_work([&](int\xA0i){printBuzz();},\xA0[&]{return\xA0(current\xA0%\xA05\xA0==\xA00\xA0&&\xA0current\xA0%\xA03\xA0!=\xA00);});\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0}\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0//\xA0printFizzBuzz()\xA0outputs\xA0"fizzbuzz".\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0void\xA0fizzbuzz(function<void()>\xA0printFizzBuzz)\xA0\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0{\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0do_work([&](int\xA0i){printFizzBuzz();},\xA0[&]{return\xA0(current\xA0%\xA05\xA0==\xA00\xA0&&\xA0current\xA0%\xA03\xA0==\xA00);});\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0}\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0//\xA0printNumber(x)\xA0outputs\xA0"x",\xA0where\xA0x\xA0is\xA0an\xA0integer.\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0void\xA0number(function<void(int)>\xA0printNumber)\xA0\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0{\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0do_work(printNumber,\xA0[&]{return\xA0(current\xA0%\xA05\xA0!=\xA00\xA0&&\xA0current\xA0%\xA03\xA0!=\xA00);});\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0}\n\xA0\xA0\xA0\xA0protected:\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0void\xA0do_work(function<void(int)>\xA0printFunc,\xA0function<bool()>\xA0evalFunc)\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0{\xA0\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0while(current\xA0<=\xA0n)\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0{\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0unique_lock<mutex>\xA0ul(mx);\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0cv.wait(ul,\xA0[&]{return\xA0(evalFunc()\xA0||\xA0current\xA0>\xA0n);});\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0if(current\xA0>\xA0n)\xA0break;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0printFunc(current);\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0++current;\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0cv.notify_all();\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0}\n\xA0\xA0\xA0\xA0\xA0\xA0\xA0\xA0}\n};\n\n```\n | 19 | 0 | ['C'] | 4 |
fizz-buzz-multithreaded | Java Solutions with Explanation (Approach 1 - object lock, Approach 2- Semaphore) | java-solutions-with-explanation-approach-c9sk | Intuition\nFour separate threads is supposed to operate on thie FizzBuzz class. We need to guard the block of code that has the logic to decide if the number is | mitesh_pv | NORMAL | 2023-01-22T04:15:06.173971+00:00 | 2023-01-22T11:47:44.685466+00:00 | 3,933 | false | # Intuition\nFour separate threads is supposed to operate on thie FizzBuzz class. We need to guard the block of code that has the logic to decide if the number is multiple of 3&5, 3|5 or none.\n\n# Approach 1 - Using Object Lock\nUsing two instance variables, `n` which is the the last number, `i` which is the currrent number to be printed.\nEach time `i` is incremented, check if it is divisible by 3, 5 according to the functions requireemnts. <br>\nAwait the thread if condition does not satisfy, else increment and notify.\n\n# Code\n```java\nclass FizzBuzz {\n private int n;\n private int i;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.i = 1;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%3==0 && i%5!=0) {\n printFizz.run();\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%3!=0 && i%5==0) {\n printBuzz.run();\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%15==0) {\n printFizzBuzz.run();\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%3!=0 && i%5!=0) {\n printNumber.accept(i);\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n}\n```\n\n# Approach 2 - Using Semaphore\nThe main logic remains same as above. <br>\nIn place of object lock, here we make use of `Semaphore`.\nWe take 3 semaphores, `fizzSem`, `buzzSem`, `fizzBuzzSem` and `numSem`. <br>\nBased on what is the next value of `currentNum` we release the required semaphore to continue. <br>\nLastly we need to make sure that the program doesn\'t goes on bounded wait, for that we need to release all the semaphores if any acquired. <br>\n\nThis is achieved in `else` part of `release()` function.\n\n# Code\n\n```java\nclass FizzBuzz {\n private int num;\n private int currentNum;\n private Semaphore fizzSem;\n private Semaphore buzzSem;\n private Semaphore fizzBuzzSem;\n private Semaphore numberSem;\n\n public FizzBuzz(int num) {\n this.num = num;\n this.currentNum = 1;\n this.fizzSem = new Semaphore(0);\n this.buzzSem = new Semaphore(0);\n this.fizzBuzzSem = new Semaphore(0);\n this.numberSem = new Semaphore(1);\n }\n\n private void release() {\n currentNum++;\n if (currentNum <= num) {\n if (currentNum % 3 == 0 && currentNum % 5 != 0) {\n fizzSem.release();\n } else if (currentNum % 3 != 0 && currentNum % 5 == 0) {\n buzzSem.release();\n } else if (currentNum % 15 == 0) {\n fizzBuzzSem.release();\n } else {\n numberSem.release();\n }\n } else {\n fizzSem.release();\n buzzSem.release();\n fizzBuzzSem.release();\n numberSem.release();\n }\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while (currentNum <= num) {\n fizzSem.acquire();\n if (currentNum <= num) {\n printFizz.run();\n }\n release();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while (currentNum <= num) {\n buzzSem.acquire();\n if (currentNum <= num) {\n printBuzz.run();\n }\n release();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (currentNum <= num) {\n fizzBuzzSem.acquire();\n if (currentNum <= num) {\n printFizzBuzz.run();\n }\n release();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while (currentNum <= num) {\n numberSem.acquire();\n if (currentNum <= num) {\n printNumber.accept(currentNum);\n }\n release();\n } \n }\n}\n``` | 18 | 0 | ['Concurrency', 'Java'] | 6 |
fizz-buzz-multithreaded | Java non-blocking solution using AtomicInteger | java-non-blocking-solution-using-atomici-cent | java\nimport java.util.ConcurrentModificationException;\nimport java.util.concurrent.atomic.AtomicInteger;\nimport java.util.function.IntConsumer;\n\nclass Fizz | dimkagorhover | NORMAL | 2019-09-19T19:16:35.155375+00:00 | 2019-09-19T19:16:35.155423+00:00 | 4,929 | false | ```java\nimport java.util.ConcurrentModificationException;\nimport java.util.concurrent.atomic.AtomicInteger;\nimport java.util.function.IntConsumer;\n\nclass FizzBuzz {\n\n private final AtomicInteger counter;\n\n private final int n;\n\n public FizzBuzz(int n) {\n this.n = n;\n counter = new AtomicInteger(1);\n }\n\n private void updateToNext(int count) {\n if (!counter.compareAndSet(count, count + 1))\n throw new ConcurrentModificationException();\n }\n\n public void fizz(Runnable printFizz) throws InterruptedException {\n int count;\n while ((count = counter.get()) <= n) {\n if (count % 3 == 0 && count % 5 != 0) {\n printFizz.run();\n updateToNext(count);\n }\n }\n }\n\n public void buzz(Runnable printBuzz) throws InterruptedException {\n int count;\n while ((count = counter.get()) <= n) {\n if (count % 3 != 0 && count % 5 == 0) {\n printBuzz.run();\n updateToNext(count);\n }\n }\n }\n\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n int count;\n while ((count = counter.get()) <= n) {\n if (count % 3 == 0 && count % 5 == 0) {\n printFizzBuzz.run();\n updateToNext(count);\n }\n }\n }\n\n public void number(IntConsumer printNumber) throws InterruptedException {\n int count;\n while ((count = counter.get()) <= n) {\n if (count % 3 != 0 && count % 5 != 0) {\n printNumber.accept(count);\n updateToNext(count);\n }\n }\n }\n}\n``` | 17 | 1 | ['Java'] | 8 |
fizz-buzz-multithreaded | Java: Fun and simple CyclicBarrier solution | java-fun-and-simple-cyclicbarrier-soluti-5oan | In this solution we use a CyclicBarrier to hold each iteration of the while loop until each thread has an opportunity to execute. Once all four threads have exe | Reves | NORMAL | 2020-03-15T16:06:36.052020+00:00 | 2020-03-15T16:11:48.963624+00:00 | 943 | false | In this solution we use a CyclicBarrier to hold each iteration of the while loop until each thread has an opportunity to execute. Once all four threads have executed, the Barrier is tripped, the counter increased, and all threads advance to the next iteration.\n\n\n```\nclass FizzBuzz {\n private int n;\n private CyclicBarrier cyclicBarrier;\n private int i;\n\n public FizzBuzz(int n) {\n this.n = n;\n cyclicBarrier = new CyclicBarrier(4, () -> i++); //Barrier tripped when all four threads call await(), which increases the counter\n i = 1;\n }\n\n public void fizz(Runnable printFizz) throws InterruptedException {\n while(i <= n){\n if(i % 3 == 0 && i % 5 != 0)\n printFizz.run();\n \n try{\n cyclicBarrier.await();\n }catch(BrokenBarrierException e){}\n }\n }\n\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while(i <= n){\n if(i % 3 != 0 && i % 5 == 0)\n printBuzz.run();\n \n try{\n cyclicBarrier.await();\n }catch(BrokenBarrierException e){}\n }\n }\n\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while(i <= n){\n if(i % 3 == 0 && i % 5 == 0)\n printFizzBuzz.run();\n \n try{\n cyclicBarrier.await();\n }catch(BrokenBarrierException e){}\n }\n }\n\n public void number(IntConsumer printNumber) throws InterruptedException {\n while(i <= n){\n if(i % 3 != 0 && i % 5 != 0)\n printNumber.accept(i);\n \n try{\n cyclicBarrier.await();\n }catch(BrokenBarrierException e){}\n }\n }\n}\n\n``` | 14 | 0 | [] | 4 |
fizz-buzz-multithreaded | Java Using Lock (Mutex Simulation) | java-using-lock-mutex-simulation-by-mjay-1nxy | Logic is pretty simple, just lock the mutex before starting any operation, check the condition, if true do the desired task, if not unlock the mutex so it can b | mjay4 | NORMAL | 2020-08-04T05:54:30.699444+00:00 | 2020-08-04T05:56:20.116390+00:00 | 2,656 | false | Logic is pretty simple, just lock the mutex before starting any operation, check the condition, if true do the desired task, if not unlock the mutex so it can be used by some other thread. For every mutex repeat the same operation.\nOne thing to note, if our count is more than n we need to unlock the mutex before it return else it will keep shifting control from one thread to another and won\'t do anything ie, We will get TLE. \nHope this helps. Let me know if u don\'t understand something and do upvote if it helps. Thank u . \n\n\n```\nclass FizzBuzz {\n private int n;\n private int count;\n private final Lock mutex = new ReentrantLock(true);\n public FizzBuzz(int n) {\n this.n = n;\n count = 1;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while(1>0){\n mutex.lock();\n if(count>n){\n mutex.unlock();\n return;\n }\n if(count%3==0 && count%5!=0){ \n printFizz.run();\n count++;\n }\n mutex.unlock();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while(1>0){\n mutex.lock();\n if(count>n){\n mutex.unlock();\n return;\n }\n if(count%3!=0 && count%5==0){ \n printBuzz.run();\n count++;\n }\n mutex.unlock();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while(1>0){\n mutex.lock();\n if(count>n){\n mutex.unlock();\n return;\n }\n if(count%3==0 && count%5==0){ \n printFizzBuzz.run();\n count++;\n }\n mutex.unlock();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while(1>0){\n mutex.lock();\n if(count>n){\n mutex.unlock();\n return;\n }\n if(count%3!=0 && count%5!=0){ \n printNumber.accept(count);\n count++;\n }\n mutex.unlock();\n }\n }\n} | 13 | 1 | ['Java'] | 1 |
fizz-buzz-multithreaded | Python 3 | 5 Approaches (Lock/Semaphore/Event/Condition) | Explanation | python-3-5-approaches-locksemaphoreevent-leqp | Explanation\n- Semaphore(1) can be used to replace Lock(), therefore 5 approaches\n- Very similar to 1116. Print Zero Even Odd\n- Make sure we have control over | idontknoooo | NORMAL | 2022-12-27T06:55:37.025076+00:00 | 2022-12-27T07:17:23.560418+00:00 | 1,876 | false | ## Explanation\n- `Semaphore(1)` can be used to replace `Lock()`, therefore 5 approaches\n- Very similar to [1116. Print Zero Even Odd](https://leetcode.com/problems/print-zero-even-odd/description/)\n- Make sure we have control over the executing order by using `Lock/Semaphore/Condition/Lock`.\n- The `Barrier` solution is slightly different, as it doens\'t really care about the executing order, but keep 4 threads in sync for each iteration. The performance might compromise a little bit as it\'s running more iterations than other solutions.\n\n## Approaches \\#1 & 2. Lock/Semaphore\n```python\nfrom threading import Lock\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.fifteen = self.n // 15\n self.three = self.n // 3 - self.fifteen\n self.five = self.n // 5 - self.fifteen\n self.rest = self.n - self.three - self.fifteen - self.five\n self.fl = Lock() # Semaphore(1)\n self.bl = Lock() # Semaphore(1)\n self.fbl = Lock() # Semaphore(1)\n self.nl = Lock() # Semaphore(1)\n self.fl.acquire()\n self.bl.acquire()\n self.fbl.acquire()\n self.cur = 1\n\n def release_lock(self, is_number_thread=False):\n if self.cur % 15 == 0:\n self.fbl.release()\n elif self.cur % 3 == 0:\n self.fl.release()\n elif self.cur % 5 == 0:\n self.bl.release()\n else:\n if not is_number_thread:\n self.nl.release()\n return True\n return False\n\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for _ in range(self.three):\n with self.fl:\n printFizz()\n self.cur += 1\n self.release_lock()\n self.fl.acquire() \n\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.five):\n with self.bl:\n printBuzz()\n self.cur += 1\n self.release_lock()\n self.bl.acquire() \n\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.fifteen):\n with self.fbl:\n printFizzBuzz()\n self.cur += 1\n self.release_lock()\n self.fbl.acquire() \n \n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for _ in range(self.rest):\n again = True \n with self.nl:\n printNumber(self.cur)\n self.cur += 1\n again = self.release_lock(is_number_thread=True)\n if not again:\n self.nl.acquire() \n```\n\n## Approaches \\#3. Condition\n```python\nfrom threading import Condition\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.c = Condition()\n self.cur = 1\n self.fb_cnt = n // 15\n self.fizz_cnt = n // 3 - self.fb_cnt\n self.buzz_cnt = n // 5 - self.fb_cnt\n self.other = n - self.fb_cnt - self.fizz_cnt - self.buzz_cnt\n\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for _ in range(self.fizz_cnt):\n with self.c:\n self.c.wait_for(lambda: self.cur % 3 == 0 and self.cur % 5 != 0)\n printFizz()\n self.cur += 1\n self.c.notify_all()\n\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.buzz_cnt):\n with self.c:\n self.c.wait_for(lambda: self.cur % 3 != 0 and self.cur % 5 == 0)\n printBuzz()\n self.cur += 1\n self.c.notify_all()\n\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.fb_cnt):\n with self.c:\n self.c.wait_for(lambda: self.cur % 15 == 0)\n printFizzBuzz()\n self.cur += 1\n self.c.notify_all()\n \n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for _ in range(self.other):\n with self.c:\n self.c.wait_for(lambda: self.cur % 15 and self.cur % 3 and self.cur % 5)\n printNumber(self.cur)\n self.cur += 1\n self.c.notify_all()\n```\n## Approaches \\#4. Event\n```python\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.ef = Event()\n self.eb = Event()\n self.efb = Event()\n self.en = Event()\n self.cur = 1\n self.fb_cnt = n // 15\n self.fizz_cnt = n // 3 - self.fb_cnt\n self.buzz_cnt = n // 5 - self.fb_cnt\n self.other = n - self.fb_cnt - self.fizz_cnt - self.buzz_cnt\n\n def set_flag(self):\n if self.cur % 15 == 0:\n self.efb.set()\n elif self.cur % 5 == 0:\n self.eb.set()\n elif self.cur % 3 == 0:\n self.ef.set()\n else:\n self.en.set()\n\n\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for _ in range(self.fizz_cnt):\n while not (self.cur % 3 == 0 and self.cur % 5 != 0):\n self.ef.wait()\n printFizz()\n self.cur += 1\n self.ef.clear()\n self.set_flag()\n\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.buzz_cnt):\n while not (self.cur % 3 != 0 and self.cur % 5 == 0):\n self.eb.wait()\n printBuzz()\n self.cur += 1\n self.eb.clear()\n self.set_flag()\n\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.fb_cnt):\n while not (self.cur % 15 == 0):\n self.efb.wait()\n printFizzBuzz()\n self.cur += 1\n self.efb.clear()\n self.set_flag()\n \n\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for _ in range(self.other):\n while not (self.cur % 15 and self.cur % 3 and self.cur % 5):\n self.en.wait()\n printNumber(self.cur)\n self.cur += 1\n self.en.clear()\n self.set_flag()\n```\n\n## Approaches \\#5. Barrier\n```python\nfrom threading import Barrier\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n + 1\n self.br = Barrier(4)\n\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 == 0 and cur % 5 != 0:\n printFizz()\n self.br.wait()\n\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 != 0 and cur % 5 == 0:\n printBuzz()\n self.br.wait()\n\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 == 0 and cur % 5 == 0:\n printFizzBuzz()\n self.br.wait()\n\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 != 0 and cur % 5 != 0:\n printNumber(cur)\n self.br.wait()\n``` | 11 | 0 | ['Concurrency', 'Python3'] | 2 |
fizz-buzz-multithreaded | Python beats 100% using Semaphore | python-beats-100-using-semaphore-by-utad-npcm | When we know N, we know how many times 3\'s multiple appears, which is N/3. We also know N/5 is the number of 5\'s multiple, N/15 is the number of 15\'s multipl | utada | NORMAL | 2019-09-19T03:30:21.238094+00:00 | 2019-09-19T03:52:13.910123+00:00 | 2,891 | false | When we know N, we know how many times 3\'s multiple appears, which is N/3. We also know N/5 is the number of 5\'s multiple, N/15 is the number of 15\'s multiple. \nTotally, we print fuzzbuzz N/15 times, print fuzz N/3-N-15 times, and print buzz N/5-N/15 times.\nWe firstly execute thread function number(),and according to x we are meeting now, we choose which kind of thread to execute and then back to thread number() until x>N.\n```\nimport threading\nclass FizzBuzz(object):\n def __init__(self, n):\n self.n = n\n self.fz = threading.Semaphore(0)\n self.bz = threading.Semaphore(0)\n self.fzbz = threading.Semaphore(0)\n self.num = threading.Semaphore(1)\n\n def fizz(self, printFizz):\n for i in range(self.n/3-self.n/15):\n self.fz.acquire()\n printFizz()\n self.num.release()\n\n def buzz(self, printBuzz):\n for i in range(self.n/5-self.n/15):\n self.bz.acquire()\n printBuzz()\n self.num.release()\n\n def fizzbuzz(self, printFizzBuzz):\n for i in range(self.n/15):\n self.fzbz.acquire()\n printFizzBuzz()\n self.num.release()\n \n def number(self, printNumber):\n for i in range(1, self.n+1):\n self.num.acquire()\n if i%3==0 and i%5 ==0:\n self.fzbz.release()\n elif i%3==0:\n self.fz.release()\n elif i%5==0:\n self.bz.release()\n else:\n printNumber(i)\n self.num.release()\n \n```\n\n | 11 | 3 | ['Python'] | 2 |
fizz-buzz-multithreaded | Multi-threaded FizzBuzz using Mutex and Condition Variable [O(n)] | multi-threaded-fizzbuzz-using-mutex-and-kfphb | Intuition\n Describe your first thoughts on how to solve this problem. \nThe code uses a mutex and condition variable to synchronize the output of the different | freddyt18 | NORMAL | 2023-04-29T14:04:49.810372+00:00 | 2023-04-29T14:04:49.810416+00:00 | 1,965 | false | # Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\nThe code uses a mutex and condition variable to synchronize the output of the different methods (fizz, buzz, fizzbuzz, and number) and ensure that they are executed in the correct order. \n\nThe wait conditions for each method are defined using lambda functions. \n\nThe private member variable "i" keeps track of the current number being printed and is incremented in each method after the corresponding output has been printed. \n\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\nThe approach used in this code is known as multi-threaded programming, which involves creating multiple threads of execution that can run concurrently to perform different tasks or parts of a task. \n\nThe use of a mutex and condition variable is a common technique for synchronizing the access to shared resources or coordinating the execution of different threads. This approach is widely used in systems programming, parallel computing, and distributed computing, among other areas.\n> This approach simplifies the logic of the wait conditions and avoids duplicating code in each method, resulting in a concise and efficient implementation of the FizzBuzz problem.\n\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\nThe time complexity of this code is O(n), where n is the maximum number to be printed. This is because each number from 1 to n is printed exactly once. \n\nThe time complexity of each of the four methods (fizz, buzz, fizzbuzz, and number) is also O(n), as each method is called exactly n/3, n/5, n/15, and (n - n/3 - n/5 + n/15) times respectively, which simplifies to O(n) for each method. The use of multi-threading does not affect the time complexity of the code, as each thread executes the same amount of work and the threads are synchronized to ensure that the output is printed in the correct order.\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\nThe space complexity of this code is O(1), which is constant space complexity. \n\nThis is because the code does not use any data structures that grow in size with the input size n. \n\nThe only memory usage is for the private member variables "n" and "i", which are integers and therefore have a constant size, as well as the mutex and condition variable, which are also constant in size. The code does not allocate any dynamic memory or use any other data structures that grow with n. Therefore, the space complexity of the code is constant and does not depend on the input size.\n\n# Code\n```\nclass FizzBuzz {\nprivate:\n int n;\n int i;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n this->i = 1;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while (true) {\n unique_lock<mutex> lock(m);\n cv.wait(lock, [&]{return (i % 3 == 0 && i % 5 != 0) || i > n;});\n if (i > n) return;\n printFizz();\n ++i;\n cv.notify_all();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while (true) {\n unique_lock<mutex> lock(m);\n cv.wait(lock, [&]{return (i % 5 == 0 && i % 3 != 0) || i > n;});\n if (i > n) return;\n printBuzz();\n ++i;\n cv.notify_all();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n void fizzbuzz(function<void()> printFizzBuzz) {\n while (true) {\n unique_lock<mutex> lock(m);\n cv.wait(lock, [&]{return i % 15 == 0 || i > n;});\n if (i > n) return;\n printFizzBuzz();\n ++i;\n cv.notify_all();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while (true) {\n unique_lock<mutex> lock(m);\n cv.wait(lock, [&]{return (i % 3 != 0 && i % 5 != 0) || i > n;});\n if (i > n) return;\n printNumber(i);\n ++i;\n cv.notify_all();\n }\n }\n\nprivate:\n mutex m;\n condition_variable cv;\n};\n\n``` | 9 | 0 | ['C++'] | 1 |
fizz-buzz-multithreaded | Python, Condition, wait_for() | python-condition-wait_for-by-marboni-qy7j | \nimport threading\nfrom functools import partial\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.cur = 1\n self.co | marboni | NORMAL | 2020-12-20T20:13:22.718978+00:00 | 2020-12-20T20:13:22.719011+00:00 | 903 | false | ```\nimport threading\nfrom functools import partial\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.cur = 1\n self.condition = threading.Condition()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n \tself._execute(lambda cur: printFizz(), lambda cur: cur % 3 == 0 and cur % 5 != 0)\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n \tself._execute(lambda cur: printBuzz(), lambda cur: cur % 3 != 0 and cur % 5 == 0)\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n self._execute(lambda cur: printFizzBuzz(), lambda cur: cur % 3 == 0 and cur % 5 == 0)\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n self._execute(lambda cur: printNumber(cur), lambda cur: cur % 3 != 0 and cur % 5 != 0)\n \n def _execute(self, func, condition_func):\n with self.condition:\n while True:\n self.condition.wait_for(lambda: condition_func(self.cur) or self.cur > self.n)\n \n try:\n if self.cur > self.n:\n return\n else:\n func(self.cur)\n self.cur += 1\n finally: \n self.condition.notify_all()\n```\t\t\t\t\t | 9 | 1 | [] | 0 |
fizz-buzz-multithreaded | C++ Very Simple Solution Using 3 Semaphores | c-very-simple-solution-using-3-semaphore-ci6d | \n#include <semaphore.h>\nclass FizzBuzz {\nprivate:\n int n;\n sem_t fizz_sem;\n sem_t buzz_sem;\n sem_t fizzbuzz_sem;\n\npublic:\n FizzBuzz(int | yehudisk | NORMAL | 2020-11-19T18:29:25.800975+00:00 | 2020-11-19T18:29:25.801015+00:00 | 1,235 | false | ```\n#include <semaphore.h>\nclass FizzBuzz {\nprivate:\n int n;\n sem_t fizz_sem;\n sem_t buzz_sem;\n sem_t fizzbuzz_sem;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n sem_init(&fizz_sem, 0, 0);\n sem_init(&buzz_sem, 0, 0);\n sem_init(&fizzbuzz_sem, 0, 0);\n }\n \n ~FizzBuzz() {\n sem_destroy(&fizz_sem);\n sem_destroy(&buzz_sem);\n sem_destroy(&fizzbuzz_sem);\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n for (int i = 3; i <= n; i += 3) {\n // divides by 3 but not by 5\n if (i % 5) { \n sem_wait(&fizz_sem);\n printFizz();\n }\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n for (int i = 5; i <= n; i += 5) {\n // divides by 5 but not by 3\n if (i % 3) {\n sem_wait(&buzz_sem);\n printBuzz();\n }\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n for (int i = 15; i <= n; i += 15) {\n sem_wait(&fizzbuzz_sem);\n printFizzBuzz();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n for (int i = 1; i <= n; i++) {\n if (i % 3 == 0) {\n if (i % 5 == 0)\n sem_post(&fizzbuzz_sem);\n else\n sem_post(&fizz_sem);\n }\n else if (i % 5 == 0)\n sem_post(&buzz_sem);\n else\n printNumber(i);\n }\n }\n};\n```\n**Like it? please upvote\nHave any comments? I\'d love to hear!** | 9 | 6 | ['C'] | 4 |
fizz-buzz-multithreaded | JAVA using Synchronized | java-using-synchronized-by-shivbaba-5w89 | \nTaking a shared variable - count. Protecting it using synchronized. If condition is not correct, wait(). Else print, increase the count and notify other waiti | shivbaba | NORMAL | 2021-07-18T17:37:21.296062+00:00 | 2021-07-18T17:37:43.041001+00:00 | 1,592 | false | \nTaking a shared variable - count. Protecting it using synchronized. If condition is not correct, wait(). Else print, increase the count and notify other waiting threads so that they can resume running. \n\nclass FizzBuzz {\n private int n;\n private int count;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.count = 1;\n }\n\n // printFizz.run() outputs "fizz".\n synchronized public void fizz(Runnable printFizz) throws InterruptedException {\n while (count <= n) {\n if (count % 3 == 0 && count % 5 != 0) {\n count++;\n printFizz.run();\n notifyAll();\n } else {\n wait();\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n synchronized public void buzz(Runnable printBuzz) throws InterruptedException {\n while (count <= n) {\n if (count % 5 == 0 && count % 3 != 0) {\n printBuzz.run();\n count++;\n notifyAll();\n } else {\n wait();\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n synchronized public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (count <= n) {\n if (count % 15 == 0) {\n printFizzBuzz.run();\n count++;\n notifyAll();\n } else {\n wait();\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n synchronized public void number(IntConsumer printNumber) throws InterruptedException {\n while (count <= n) {\n if (count % 3 == 0 || count % 5 == 0) {\n wait();\n } else {\n printNumber.accept(count);\n count++;\n notifyAll();\n }\n }\n }\n} | 8 | 0 | ['Java'] | 2 |
fizz-buzz-multithreaded | Easy Mutex Solution || Love Babbar Approach || Best Way 🔥🔥 | easy-mutex-solution-love-babbar-approach-q2k6 | Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time | abhi_pandit_18 | NORMAL | 2023-07-13T06:09:11.805113+00:00 | 2023-07-13T06:09:11.805158+00:00 | 1,339 | false | # Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass FizzBuzz {\nprivate:\n int n;\n mutex m;\n condition_variable c;\n int i;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n this->i = 1;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while(i<=n)\n {\n unique_lock<mutex> lock(m);\n while(i<=n && (((i%3) == 0) && ((i%5) != 0)) == 0)\n {\n c.wait(lock);\n }\n if(i<=n)\n {\n printFizz();\n i++;\n }\n c.notify_all();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while(i<=n)\n {\n unique_lock<mutex> lock(m);\n while(i<=n && (((i%3) != 0) && ((i%5) == 0)) == 0)\n {\n c.wait(lock);\n }\n if(i<=n)\n {\n printBuzz();\n i++;\n }\n c.notify_all();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while(i<=n)\n {\n unique_lock<mutex> lock(m);\n while(i<=n && (((i%3) == 0) && ((i%5) == 0)) == 0)\n {\n c.wait(lock);\n }\n if(i<=n)\n {\n printFizzBuzz();\n i++;\n }\n c.notify_all();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while(i<=n)\n {\n unique_lock<mutex> lock(m);\n while(i<=n && (((i%3) != 0) && ((i%5) != 0)) == 0)\n {\n c.wait(lock);\n }\n if(i<=n)\n {\n printNumber(i++);\n }\n c.notify_all();\n }\n }\n};\n``` | 7 | 0 | ['C++'] | 3 |
fizz-buzz-multithreaded | Java wait/notifyAll | java-waitnotifyall-by-softarium-lsuu | \nclass FizzBuzz {\n private final int max;\n private int counter = 1;\n public FizzBuzz(int n) { this.max = n; }\n\n private synchronized void sync | softarium | NORMAL | 2021-12-03T21:02:49.845025+00:00 | 2021-12-03T21:02:49.845051+00:00 | 578 | false | ```\nclass FizzBuzz {\n private final int max;\n private int counter = 1;\n public FizzBuzz(int n) { this.max = n; }\n\n private synchronized void synchronizedPrint(final Runnable print, final IntPredicate predicate) throws InterruptedException {\n while (counter <= max) {\n if (predicate.test(counter)) {\n print.run();\n counter++;\n this.notifyAll();\n } else {\n this.wait();\n }\n }\n }\n\n public void fizz(final Runnable printFizz) throws InterruptedException {\n synchronizedPrint(printFizz, n -> n % 3 == 0 && n % 5 != 0);\n }\n\n public void buzz(final Runnable printBuzz) throws InterruptedException {\n synchronizedPrint(printBuzz, n -> n % 5 == 0 && n % 3 != 0);\n }\n\n public void fizzbuzz(final Runnable printFizzBuzz) throws InterruptedException {\n synchronizedPrint(printFizzBuzz, n -> n % 15 == 0);\n }\n\n public void number(final IntConsumer printNumber) throws InterruptedException {\n synchronizedPrint(() -> printNumber.accept(counter), n -> n % 3 != 0 && n % 5 != 0);\n }\n}\n``` | 7 | 0 | [] | 2 |
fizz-buzz-multithreaded | Java - 8 ms - Use a semaphore with one permit | java-8-ms-use-a-semaphore-with-one-permi-grjy | \nclass FizzBuzz {\n private static int NUMBER_OF_PRINT_LICENSES = 1;\n \n private int n;\n private int printIndex;\n private Semaphore printLice | ed-karabinus | NORMAL | 2021-04-18T07:06:43.201147+00:00 | 2021-04-18T07:06:43.201190+00:00 | 928 | false | ```\nclass FizzBuzz {\n private static int NUMBER_OF_PRINT_LICENSES = 1;\n \n private int n;\n private int printIndex;\n private Semaphore printLicense;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.printIndex = 1;\n this.printLicense = new Semaphore(NUMBER_OF_PRINT_LICENSES);\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n runRunnableBasedOnPredicate(\n printFizz, \n (printIndex) -> printIndex % 3 == 0 && printIndex % 15 != 0\n );\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n runRunnableBasedOnPredicate(\n printBuzz, \n (printIndex) -> printIndex % 5 == 0 && printIndex % 15 != 0\n );\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n runRunnableBasedOnPredicate(\n printFizzBuzz, \n (printIndex) -> printIndex % 15 == 0\n );\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while (shouldLoopContinue()) {\n printLicense.acquire();\n if (shouldLoopContinue() &&\n printIndex % 3 != 0 && \n printIndex % 5 != 0\n ) {\n printNumber.accept(printIndex);\n printIndex++;\n }\n printLicense.release();\n }\n }\n \n private void runRunnableBasedOnPredicate(\n Runnable runnable, \n Predicate<Integer> predicate\n ) throws InterruptedException {\n while (shouldLoopContinue()) {\n printLicense.acquire();\n if (shouldLoopContinue() && \n predicate.test(printIndex)\n ) {\n runnable.run();\n printIndex++;\n }\n printLicense.release();\n }\n }\n \n private Boolean shouldLoopContinue() {\n return printIndex <= n;\n }\n}\n``` | 7 | 0 | ['Java'] | 4 |
fizz-buzz-multithreaded | Beats 100% Other Solutions | beats-100-other-solutions-by-day_tripper-8b69 | \nimport threading\n\nclass FizzBuzz:\n def __init__(self, n: int): \n self.n = n\n self.f = threading.Lock()\n self.b = threading. | Day_Tripper | NORMAL | 2022-07-21T03:41:39.874544+00:00 | 2022-07-21T03:41:39.874588+00:00 | 1,314 | false | ```\nimport threading\n\nclass FizzBuzz:\n def __init__(self, n: int): \n self.n = n\n self.f = threading.Lock()\n self.b = threading.Lock()\n self.fb = threading.Lock()\n self.f.acquire()\n self.b.acquire()\n self.fb.acquire()\n self.main = threading.Lock()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n while True:\n self.f.acquire()\n if self.n == 0 :\n return\n printFizz()\n self.main.release()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n while True:\n self.b.acquire()\n if self.n == 0:\n return\n printBuzz()\n self.main.release()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n while True:\n self.fb.acquire()\n if self.n == 0:\n return\n printFizzBuzz()\n self.main.release()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for i in range(1, self.n+1):\n #print("number:",i)\n self.main.acquire()\n if i % 15 == 0:\n self.fb.release()\n elif i % 3 == 0:\n self.f.release()\n elif i % 5 == 0:\n self.b.release()\n else:\n printNumber(i)\n self.main.release()\n\n self.main.acquire() \n self.n = 0\n self.f.release()\n self.b.release()\n self.fb.release()\n return\n``` | 6 | 0 | [] | 0 |
fizz-buzz-multithreaded | C++, single mutex, but not spinlock or roundrobin | c-single-mutex-but-not-spinlock-or-round-x8vz | Each thread checks for its unique condition, so it\'s safe but slower\n\nclass FizzBuzz {\nprivate:\n int n;\n int current_number;\n mutex number_mutex | nalivai | NORMAL | 2020-09-09T20:18:25.881308+00:00 | 2020-09-09T20:21:39.877324+00:00 | 1,328 | false | Each thread checks for its unique condition, so it\'s safe but slower\n```\nclass FizzBuzz {\nprivate:\n int n;\n int current_number;\n mutex number_mutex;\n const int number_of_threads = 4;\n bool done = true;\n \npublic:\n FizzBuzz(int n) {\n this->n = n;\n if (n > 0){\n done = false;\n }\n current_number = 1;\n }\n\nprivate: \n void nextNumber(){\n if (current_number < n){\n scoped_lock lock(number_mutex);\n current_number++;\n } else{\n done = true;\n }\n }\n\npublic: \n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) { \n while (!done){\n if (!(current_number % 3 ) && (current_number % 5)){\n printFizz();\n nextNumber(); \n }\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) { \n while (!done){\n if ((current_number % 3 ) && !(current_number % 5)){\n printBuzz();\n nextNumber(); \n }\n }\n }\n \n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while (!done){\n if (!(current_number % 3 ) && !(current_number % 5)){\n printFizzBuzz();\n nextNumber(); \n }\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n \n while (!done){\n if ((current_number % 3 ) && (current_number % 5)){\n printNumber(current_number);\n nextNumber(); \n }\n }\n }\n};\n``` | 6 | 0 | ['C', 'C++'] | 2 |
fizz-buzz-multithreaded | C# SemaphoreSlim Array | c-semaphoreslim-array-by-olegbelousov77-ci49 | csharp\nusing System.Threading;\n\npublic class FizzBuzz {\n \n private enum FizzBuzzEnum {\n Fizz = 0,\n Buzz = 1,\n FizzBuzz = 2,\n | olegbelousov77 | NORMAL | 2021-11-21T21:13:27.148870+00:00 | 2021-11-21T21:13:27.148922+00:00 | 658 | false | ```csharp\nusing System.Threading;\n\npublic class FizzBuzz {\n \n private enum FizzBuzzEnum {\n Fizz = 0,\n Buzz = 1,\n FizzBuzz = 2,\n Number = 3\n }\n \n private int _n;\n private int _k;\n private SemaphoreSlim[] _semaphores;\n private CancellationTokenSource _cts;\n\n public FizzBuzz(int n) {\n _n = n;\n _k = 0;\n _semaphores = Enum\n .GetValues<FizzBuzzEnum>()\n .Select(v => new SemaphoreSlim(0,1))\n .ToArray();\n _cts = new CancellationTokenSource();\n _semaphores[(int)GetFizzBuzz(++_k)].Release();\n }\n\n public void Fizz(Action printFizz) => \n Execute(FizzBuzzEnum.Fizz, printFizz);\n\n public void Buzz(Action printBuzz) => \n Execute(FizzBuzzEnum.Buzz, printBuzz);\n\n public void Fizzbuzz(Action printFizzBuzz) => \n Execute(FizzBuzzEnum.FizzBuzz, printFizzBuzz);\n\n public void Number(Action<int> printNumber) => \n Execute(FizzBuzzEnum.Number, () => printNumber(_k));\n \n private void Execute(FizzBuzzEnum fizzbuzz, Action action) {\n try {\n while (_k <= _n) {\n _semaphores[(int)fizzbuzz].Wait(_cts.Token);\n if (_k <= _n) {\n action();\n _semaphores[(int)GetFizzBuzz(++_k)].Release();\n }\n }\n _cts.Cancel();\n } catch (OperationCanceledException) {\n \n }\n }\n \n private FizzBuzzEnum GetFizzBuzz(int i) {\n if (i % 3 == 0 && i % 5 == 0)\n return FizzBuzzEnum.FizzBuzz;\n if (i % 3 == 0 && i % 5 != 0)\n return FizzBuzzEnum.Fizz;\n if (i % 3 != 0 && i % 5 == 0)\n return FizzBuzzEnum.Buzz;\n return FizzBuzzEnum.Number;\n }\n}\n``` | 5 | 0 | ['C#'] | 1 |
fizz-buzz-multithreaded | Python3 four locks | python3-four-locks-by-mxmb-vp6p | python\nimport threading as t\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.count = 1\n self.num_lock, self.fizz_lo | mxmb | NORMAL | 2021-08-21T18:57:49.406449+00:00 | 2021-08-21T19:01:07.556241+00:00 | 937 | false | ```python\nimport threading as t\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.count = 1\n self.num_lock, self.fizz_lock, self.buzz_lock, self.fizzbuzz_lock = t.Lock(), t.Lock(), t.Lock(), t.Lock()\n self.fizz_lock.acquire()\n self.buzz_lock.acquire()\n self.fizzbuzz_lock.acquire()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for _ in range(self.n//3-self.n//15):\n self.fizz_lock.acquire()\n printFizz()\n self.num_lock.release()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.n//5-self.n//15):\n self.buzz_lock.acquire()\n printBuzz()\n self.num_lock.release()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for _ in range(self.n//15):\n self.fizzbuzz_lock.acquire()\n printFizzBuzz()\n self.num_lock.release()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for i in range(1,self.n+1):\n self.num_lock.acquire()\n if not i%15:\n self.fizzbuzz_lock.release()\n elif not i%3:\n self.fizz_lock.release()\n elif not i%5:\n self.buzz_lock.release()\n else:\n printNumber(i)\n self.num_lock.release()\n``` | 5 | 0 | ['Python', 'Python3'] | 1 |
fizz-buzz-multithreaded | Java Solution with Locks | java-solution-with-locks-by-anjana9-o0it | \nclass FizzBuzz {\n private int n;\n private int count;\n private Object lock;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.coun | anjana9 | NORMAL | 2020-10-12T05:49:06.750774+00:00 | 2020-10-12T05:56:42.269903+00:00 | 1,289 | false | ```\nclass FizzBuzz {\n private int n;\n private int count;\n private Object lock;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.count = 1;\n this.lock = new Object();\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while(count<=n) {\n synchronized (lock) {\n if (count<=n && count % 3 == 0 && count % 5 != 0) {\n printFizz.run();\n count++;\n }\n }\n\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while(count<=n) {\n synchronized (lock) {\n if (count<=n && count % 5 == 0 && count % 3 != 0) {\n printBuzz.run();\n count++;\n }\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while(count<=n) {\n synchronized (lock) {\n if (count<=n && count % 5 == 0 && count % 3 == 0) {\n printFizzBuzz.run();\n count++;\n }\n }\n }\n\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while(count<=n) {\n synchronized (lock) {\n if (count<=n && count % 3 != 0 && count % 5 != 0) {\n printNumber.accept(count);\n count++;\n }\n }\n }\n }\n}\n``` | 5 | 1 | ['Java'] | 6 |
fizz-buzz-multithreaded | Easy C !! One mutex and One Condition variable. | easy-c-one-mutex-and-one-condition-varia-5gzi | Use the mutex for locking the current number.\n- Fizz() thread sleeps on the condition variable if either the current number is divisible by 5 or not divisible | csd2592 | NORMAL | 2019-10-13T00:50:11.498111+00:00 | 2019-10-13T00:50:11.498147+00:00 | 1,048 | false | Use the mutex for locking the current number.\n- Fizz() thread sleeps on the condition variable if either the current number is divisible by 5 or not divisible by 3.\n- Buzz() thread sleeps on the condition variable if either the current number is divisible by 3 or not divisible by 5.\n- FizzBuzz() thread sleeps on the condition variable if either the current number is not divisible by 3 or not divisible by 5.\n- Number() thread sleeps on the condition variable if either the current number is divisible by 3 or divisible by 5. \n\n```\n#include <stdlib.h>\n#include <stdio.h>\n#include <pthread.h>\n\n\ntypedef struct {\n int n;\n int curr;\n pthread_mutex_t m;\n pthread_cond_t cv;\n} FizzBuzz;\n\nFizzBuzz* fizzBuzzCreate(int n) {\n FizzBuzz* obj = (FizzBuzz*) malloc(sizeof(FizzBuzz));\n obj->n = n;\n obj->curr = 1;\n pthread_mutex_init(&obj->m, NULL);\n pthread_cond_init(&obj->cv, NULL);\n return obj;\n}\n\n// printFizz() outputs "fizz".\nvoid fizz(FizzBuzz* obj) {\n while (1) {\n pthread_mutex_lock(&obj->m);\n while (obj->curr <= obj->n &&\n (obj->curr % 5 == 0 || obj->curr % 3 != 0)) {\n pthread_cond_wait(&obj->cv, &obj->m);\n }\n\n if (obj->curr > obj->n) {\n pthread_mutex_unlock(&obj->m);\n return;\n }\n\n printFizz();\n obj->curr++;\n pthread_cond_broadcast(&obj->cv);\n pthread_mutex_unlock(&obj->m);\n }\n}\n\n// printBuzz() outputs "buzz".\nvoid buzz(FizzBuzz* obj) {\n while (1) {\n pthread_mutex_lock(&obj->m);\n while (obj->curr <= obj->n &&\n (obj->curr % 5 != 0 || obj->curr % 3 == 0)) {\n pthread_cond_wait(&obj->cv, &obj->m);\n }\n\n if (obj->curr > obj->n) {\n pthread_mutex_unlock(&obj->m);\n return;\n }\n\n printBuzz();\n obj->curr++;\n pthread_cond_broadcast(&obj->cv);\n pthread_mutex_unlock(&obj->m);\n } \n}\n\n// printFizzBuzz() outputs "fizzbuzz".\nvoid fizzbuzz(FizzBuzz* obj) {\n while (1) {\n pthread_mutex_lock(&obj->m);\n while (obj->curr <= obj->n &&\n (obj->curr % 5 != 0 || obj->curr % 3 != 0)) {\n pthread_cond_wait(&obj->cv, &obj->m);\n }\n\n if (obj->curr > obj->n) {\n pthread_mutex_unlock(&obj->m);\n return;\n }\n\n printFizzBuzz();\n obj->curr++;\n pthread_cond_broadcast(&obj->cv);\n pthread_mutex_unlock(&obj->m);\n } \n}\n\n// You may call global function `void printNumber(int x)`\n// to output "x", where x is an integer.\nvoid number(FizzBuzz* obj) {\n while (1) {\n pthread_mutex_lock(&obj->m);\n while (obj->curr <= obj->n &&\n (obj->curr % 5 == 0 || obj->curr % 3 == 0)) {\n pthread_cond_wait(&obj->cv, &obj->m);\n }\n\n if (obj->curr > obj->n) {\n pthread_mutex_unlock(&obj->m);\n return;\n }\n\n printNumber(obj->curr);\n obj->curr++;\n pthread_cond_broadcast(&obj->cv);\n pthread_mutex_unlock(&obj->m);\n } \n}\n\nvoid fizzBuzzFree(FizzBuzz* obj) {\n pthread_mutex_destroy(&obj->m);\n pthread_cond_destroy(&obj->cv);\n free(obj);\n}\n``` | 5 | 0 | [] | 0 |
fizz-buzz-multithreaded | Python using just 1 Semaphore | python-using-just-1-semaphore-by-lamnguy-38i4 | Unlike other solutions which use 4 semaphores, mine uses just one. This sole semaphore acts as a lock that prevent concurrent access to self.cur. Whenever one o | lamnguyen2187 | NORMAL | 2019-09-20T00:23:41.493327+00:00 | 2019-09-20T00:23:41.493374+00:00 | 1,296 | false | Unlike other solutions which use 4 semaphores, mine uses just one. This sole semaphore acts as a lock that prevent concurrent access to `self.cur`. Whenever one of `fizz`, `buzz`, `fizzbuzz`, and `number` manages to acquire the lock, it checks if if its turn and act accordingly it if is. Before releasing the lock, it increases `self.cur` by `1`. When `self.cur` becomes bigger than `self.n`, all the while loops in these 4 functions are terminated.\n\n```\nimport threading\n\nclass FizzBuzz(object):\n def __init__(self, n):\n self.n = n\n self.cur = 1\n self.sem = threading.Semaphore(1)\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz):\n """\n :type printFizz: method\n :rtype: void\n """\n while True:\n self.sem.acquire()\n if self.cur <= self.n and self.cur % 3 == 0 and self.cur % 5 != 0:\n printFizz()\n self.cur += 1\n self.sem.release()\n \n if self.cur > self.n:\n break\n \t\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz):\n """\n :type printBuzz: method\n :rtype: void\n """\n while True:\n self.sem.acquire()\n if self.cur <= self.n and self.cur % 5 == 0 and self.cur % 3 != 0:\n printBuzz()\n self.cur += 1\n self.sem.release()\n\n if self.cur > self.n:\n break\n \t\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz):\n """\n :type printFizzBuzz: method\n :rtype: void\n """\n while True:\n self.sem.acquire()\n if self.cur <= self.n and self.cur % 3 == 0 and self.cur % 5 == 0:\n printFizzBuzz()\n self.cur += 1\n self.sem.release()\n \n if self.cur > self.n:\n break\n\t\t\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber):\n """\n :type printNumber: method\n :rtype: void\n """\n while True:\n self.sem.acquire() \n if self.cur <= self.n and self.cur % 3 != 0 and self.cur % 5 != 0:\n printNumber(self.cur)\n self.cur += 1\n self.sem.release()\n \n if self.cur > self.n:\n break\n``` | 5 | 3 | [] | 1 |
fizz-buzz-multithreaded | Python clean symmetric solution using Condition | python-clean-symmetric-solution-using-co-z2lf | It may not be as fast as the most voted python solution but I think it\'s more concise in a sense that all 4 methods do the same thing but just the condition to | redtree1112 | NORMAL | 2022-02-26T07:30:23.774228+00:00 | 2022-02-26T07:30:23.774260+00:00 | 563 | false | It may not be as fast as the most voted python solution but I think it\'s more concise in a sense that all 4 methods do the same thing but just the condition to wait is different.\n\n```\nfrom threading import *\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.cur = 1\n self.cond = Condition()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n while True:\n with self.cond:\n self.cond.wait_for(lambda: self.cur > self.n or (self.cur % 3 == 0 and self.cur % 5 != 0))\n if self.cur > self.n:\n return\n printFizz()\n self.cur += 1\n self.cond.notify_all()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n while True:\n \t with self.cond:\n self.cond.wait_for(lambda: self.cur > self.n or (self.cur % 3 != 0 and self.cur % 5 == 0))\n if self.cur > self.n:\n return\n printBuzz()\n self.cur += 1\n self.cond.notify_all()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n while True:\n with self.cond:\n self.cond.wait_for(lambda: self.cur > self.n or (self.cur % 3 == 0 and self.cur % 5 == 0))\n if self.cur > self.n:\n return\n printFizzBuzz()\n self.cur += 1\n self.cond.notify_all()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n while True:\n with self.cond:\n self.cond.wait_for(lambda: self.cur > self.n or (self.cur % 3 != 0 and self.cur % 5 != 0))\n if self.cur > self.n:\n return\n printNumber(self.cur)\n self.cur += 1\n self.cond.notify_all()\n \n \n \n``` | 4 | 0 | [] | 1 |
fizz-buzz-multithreaded | C++ | Condition Variable | c-condition-variable-by-vineet0692-5lw8 | We can take advantage of condition variables predicate feature to our advantage so that only one thread is waken up to do its job.\n\n\nclass FizzBuzz {\nprivat | vineet0692 | NORMAL | 2021-07-03T16:40:41.273492+00:00 | 2021-07-03T16:40:41.273532+00:00 | 459 | false | We can take advantage of condition variables predicate feature to our advantage so that only one thread is waken up to do its job.\n\n```\nclass FizzBuzz {\nprivate:\n int n;\n int i;\n mutex mtx;\n condition_variable cv;\n\npublic:\n FizzBuzz(int n) {\n i = 1;\n this->n = n;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while( true ){\n unique_lock<mutex> lock(mtx);\n cv.wait(lock, [this](){return i>n || (i%3 == 0 && i%5 != 0);});\n if( i > n ) break;\n printFizz(); i++;\n cv.notify_all();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while( true ){\n unique_lock<mutex> lock(mtx);\n cv.wait(lock, [this]{return i>n || (i%3 != 0 && i%5 == 0);});\n if( i > n ) break;\n printBuzz(); i++;\n cv.notify_all();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while( true ){\n unique_lock<mutex> lock(mtx);\n cv.wait(lock, [this]{return i>n || (i%3 == 0 && i%5 == 0);});\n if( i > n ) break;\n printFizzBuzz(); i++;\n cv.notify_all();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while( true ){\n unique_lock<mutex> lock(mtx);\n cv.wait(lock, [this]{return i>n || (i%3 != 0 && i%5 != 0);});\n if( i > n ) break;\n printNumber(i++);\n cv.notify_all();\n }\n }\n};\n``` | 4 | 0 | [] | 0 |
fizz-buzz-multithreaded | C++ condition variable based sln, clean code | c-condition-variable-based-sln-clean-cod-y30g | ```\nclass FizzBuzz {\nprivate:\n int n;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n }\n\n void do_staff(function check, function print) | dmitrii_bokovikov | NORMAL | 2021-03-24T17:44:10.391240+00:00 | 2021-03-24T17:44:10.391281+00:00 | 573 | false | ```\nclass FizzBuzz {\nprivate:\n int n;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n }\n\n void do_staff(function<bool()> check, function<void()> print) {\n while (true) {\n unique_lock lck(mt);\n cv.wait(lck, [&check, this]() { return std::invoke(check) || current > n; });\n if (current <= n) {\n print();\n }\n \n ++current;\n cv.notify_all();\n if (current > n) {\n break;\n }\n }\n }\n \n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n do_staff([this]() { return current % 3 == 0 && current % 5 != 0; }, printFizz);\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n do_staff([this]() { return current % 3 != 0 && current % 5 == 0; }, printBuzz);\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n do_staff([this]() { return current % 3 == 0 && current % 5 == 0; }, printFizzBuzz);\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n do_staff([this]() { return current % 3 != 0 && current % 5 != 0; }, [printNumber, this]() {printNumber(current);});\n }\n \n mutex mt;\n condition_variable cv;\n int current = 1;\n}; | 4 | 0 | [] | 1 |
fizz-buzz-multithreaded | Python3 solution using barrier | python3-solution-using-barrier-by-johnny-gwrs | python\nfrom threading import Barrier\n\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.barrier = Barrier(4)\n\n # prin | johnny5 | NORMAL | 2021-01-01T13:10:13.977714+00:00 | 2021-01-01T13:10:13.977743+00:00 | 453 | false | ```python\nfrom threading import Barrier\n\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.barrier = Barrier(4)\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for number in range(1, self.n+1):\n if number % 3 == 0 and number % 5:\n printFizz()\n self.barrier.wait()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for number in range(1, self.n+1):\n if number % 3 and number % 5 == 0:\n printBuzz()\n self.barrier.wait()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for number in range(1, self.n+1):\n if number % 15 == 0:\n printFizzBuzz()\n self.barrier.wait()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for number in range(1, self.n+1):\n if number % 3 and number % 5:\n printNumber(number)\n self.barrier.wait()\n``` | 4 | 0 | [] | 3 |
fizz-buzz-multithreaded | C# basic lock approach | c-basic-lock-approach-by-superfooman-oq2a | \npublic class FizzBuzz {\n private int n;\n private static int count = 1;\n private Object baton = new Object();\n\t\n\tpublic FizzBuzz(int n) {\n | superfooman | NORMAL | 2020-12-09T04:05:53.134172+00:00 | 2020-12-09T04:05:53.134222+00:00 | 306 | false | ```\npublic class FizzBuzz {\n private int n;\n private static int count = 1;\n private Object baton = new Object();\n\t\n\tpublic FizzBuzz(int n) {\n this.n = n;\n }\n\t\n private void syncRun(Func<int, bool> condition, Action<int> action){\n\t\twhile(true){ \n lock(baton){\n \n if(count > n)\n return;\n \n if(condition(count)){\n action(count);\n count++;\n }\n }\n }\n }\n\t\n // printFizz() outputs "fizz".\n public void Fizz(Action printFizz) {\n syncRun( i => i%3 == 0 && i%5 != 0, x => printFizz());\n }\n\n // printBuzzz() outputs "buzz".\n public void Buzz(Action printBuzz) {\n syncRun( i => i%5 == 0 && i%3 != 0, x => printBuzz());\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n public void Fizzbuzz(Action printFizzBuzz) {\n syncRun( i => i%3 == 0 && i%5== 0 , x => printFizzBuzz());\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n public void Number(Action<int> printNumber) {\n syncRun( i => i%3 != 0 && i%5 != 0 , x => printNumber(x)); \n }\n \n}\n``` | 4 | 0 | [] | 0 |
fizz-buzz-multithreaded | C# using Barrier | c-using-barrier-by-polybios-f0k0 | \nusing System.Threading;\npublic class FizzBuzz {\n \n private int n;\n private Barrier b = new Barrier(4);\n\n public FizzBuzz(int n)\n {\n | polybios | NORMAL | 2020-06-06T17:17:40.531487+00:00 | 2020-06-06T17:19:24.107535+00:00 | 562 | false | ```\nusing System.Threading;\npublic class FizzBuzz {\n \n private int n;\n private Barrier b = new Barrier(4);\n\n public FizzBuzz(int n)\n {\n this.n = n;\n }\n\n // printFizz() outputs "fizz".\n public void Fizz(Action printFizz)\n {\n for (int i = 1; i <= n; ++i)\n {\n if (i % 3 == 0 && i % 5 != 0) printFizz();\n b.SignalAndWait();\n }\n }\n\n // printBuzzz() outputs "buzz".\n public void Buzz(Action printBuzz)\n {\n for (int i = 1; i <= n; ++i)\n {\n if (i % 3 != 0 && i % 5 == 0) printBuzz();\n b.SignalAndWait();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n public void Fizzbuzz(Action printFizzBuzz)\n {\n for (int i = 1; i <= n; ++i)\n {\n if (i % 3 == 0 && i % 5 == 0) printFizzBuzz();\n b.SignalAndWait();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n public void Number(Action<int> printNumber)\n {\n for (int i = 1; i <= n; ++i)\n {\n if (i % 3 != 0 && i % 5 != 0) printNumber(i);\n b.SignalAndWait();\n }\n }\n}\n``` | 4 | 0 | [] | 5 |
fizz-buzz-multithreaded | Python using Condition and Lock | python-using-condition-and-lock-by-lacg-3cbs | The other solutions I saw used Semaphores, so I am just sharing mine that is using Lock and Condition.\nI hope it can help someone.\nThe idea behind the lock is | lacg | NORMAL | 2019-10-14T15:53:20.947549+00:00 | 2019-10-14T17:02:01.845875+00:00 | 1,236 | false | The other solutions I saw used Semaphores, so I am just sharing mine that is using Lock and Condition.\nI hope it can help someone.\nThe idea behind the lock is to avoid the other threads look at the counter while one of the process updates its value.\nAlso, if one thread have the right condition, all the other threads wait until the right condition thread updates the count and notify all to wake the sleeping threads.\n\n```\nfrom threading import Condition, Lock\n\n\nclass FizzBuzz:\n\n def __init__(self, n: int):\n self.n = n\n self.count = 1\n self.condition = Condition()\n self.lock = Lock()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n with self.condition:\n while self.count <= self.n:\n if not self.count % 3 and self.count % 5:\n self.lock.acquire()\n printFizz()\n self.count += 1\n self.lock.release()\n self.condition.notifyAll()\n else:\n self.condition.wait()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n with self.condition:\n while self.count <= self.n:\n if not self.count % 5 and self.count % 3:\n self.lock.acquire()\n printBuzz()\n self.count += 1\n self.lock.release()\n self.condition.notifyAll()\n else:\n self.condition.wait()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n with self.condition:\n while self.count <= self.n:\n if not self.count % 3 and not self.count % 5:\n self.lock.acquire()\n printFizzBuzz()\n self.count += 1\n self.lock.release()\n self.condition.notifyAll()\n else:\n self.condition.wait()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n with self.condition:\n while self.count <= self.n:\n if self.count % 3 and self.count % 5:\n self.lock.acquire()\n printNumber(self.count)\n self.count += 1\n self.lock.release()\n self.condition.notifyAll()\n else:\n self.condition.wait()\n```\n\nAnd then we can improve it to:\n\n```\nfrom threading import Condition, Lock\nfrom inspect import signature\n\n\nclass FizzBuzz:\n\n def __init__(self, n: int):\n self.n = n\n self.count = 1\n self.condition = Condition()\n self.lock = Lock()\n\n def produce(self, cond, func) -> None:\n with self.condition:\n while self.count <= self.n:\n if cond(self.count):\n self.lock.acquire()\n if list(signature(func).parameters):\n func(self.count)\n else:\n func()\n self.count += 1\n self.lock.release()\n self.condition.notifyAll()\n else:\n self.condition.wait()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n lFizz = lambda i: not i % 3 and i % 5\n self.produce(lFizz, printFizz)\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n lBuzz = lambda i: not i % 5 and i % 3\n self.produce(lBuzz, printBuzz)\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n lFizzBuzz = lambda i: not i % 3 and not i % 5\n self.produce(lFizzBuzz, printFizzBuzz)\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n lNumber = lambda i: i % 3 and i % 5\n self.produce(lNumber, printNumber)\n``` | 4 | 0 | ['Python', 'Python3'] | 2 |
fizz-buzz-multithreaded | Python 100% Semaphore | python-100-semaphore-by-awice-y8i1 | \nfrom threading import Semaphore\n\nclass FizzBuzz(object):\n def __init__(self, n):\n self.n = n\n self.sem0 = Semaphore(1)\n self.sem | awice | NORMAL | 2019-09-21T23:51:47.160892+00:00 | 2019-09-21T23:51:47.160946+00:00 | 1,185 | false | ```\nfrom threading import Semaphore\n\nclass FizzBuzz(object):\n def __init__(self, n):\n self.n = n\n self.sem0 = Semaphore(1)\n self.sem3 = Semaphore(0)\n self.sem5 = Semaphore(0)\n self.sem15 = Semaphore(0)\n\n def fizz(self, printFizz):\n for i in xrange(3, self.n + 1, 3):\n if i % 15:\n self.sem3.acquire()\n printFizz()\n self._release(i+1)\n \n def buzz(self, printBuzz):\n for i in xrange(5, self.n + 1, 5):\n if i % 15:\n self.sem5.acquire()\n printBuzz()\n self._release(i+1)\n \n def fizzbuzz(self, printFizzBuzz):\n for i in xrange(15, self.n + 1, 15):\n self.sem15.acquire()\n printFizzBuzz()\n self._release(i+1)\n\n def number(self, printNumber):\n for i in xrange(1, self.n + 1):\n if i % 3 and i % 5:\n self.sem0.acquire()\n printNumber(i)\n self._release(i+1)\n \n def _release(self, i):\n if i % 3 and i % 5:\n self.sem0.release()\n elif i % 5:\n self.sem3.release()\n elif i % 3:\n self.sem5.release()\n else:\n self.sem15.release()\n``` | 4 | 0 | [] | 0 |
fizz-buzz-multithreaded | very simple and easy to understand solution | very-simple-and-easy-to-understand-solut-xa3o | Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time | Kishore_raok | NORMAL | 2024-04-25T06:08:56.256227+00:00 | 2024-04-25T06:08:56.256255+00:00 | 570 | false | # Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass FizzBuzz {\n private int n;\n Semaphore A,B,C,D;\n public FizzBuzz(int n) {\n this.n = n;\n A = new Semaphore(1);\n B = new Semaphore(0);\n C = new Semaphore(0);\n D = new Semaphore(0);\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for(int i =1;i<=n;i++){\n A.acquire();\n if(i%3==0 && i%5 != 0){\n printFizz.run();\n }\n B.release();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for(int i =1;i<=n;i++){\n B.acquire();\n if(i%3 != 0 && i%5 == 0){\n printBuzz.run();\n }\n C.release();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for(int i =1;i<=n;i++){\n C.acquire();\n if(i%3==0 && i%5 == 0){\n printFizzBuzz.run();\n }\n D.release();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n for(int i =1;i<=n;i++){\n D.acquire();\n if(i%3 !=0 && i%5 != 0){\n printNumber.accept(i);\n }\n A.release();\n }\n }\n}\n\n\n\n\n \n``` | 3 | 0 | ['Java'] | 2 |
fizz-buzz-multithreaded | Optimized Lock-Free C++ Solution with atomics | optimized-lock-free-c-solution-with-atom-9gkz | Approach\n- Using cache-line-sized alignment for atomics\n- Using weak memory ordering where possible\n- Using yield() instead of waiting\n\n# Code\n\nclass Fiz | nikmy | NORMAL | 2023-02-21T12:25:33.066340+00:00 | 2023-02-21T12:27:00.066462+00:00 | 747 | false | # Approach\n- Using cache-line-sized alignment for atomics\n- Using weak memory ordering where possible\n- Using `yield()` instead of waiting\n\n# Code\n```\nclass FizzBuzz {\nprivate:\n int n;\n atomic_int i{1};\n\n alignas(64) atomic_bool n_turn {true} ;\n alignas(64) atomic_bool f_turn {false};\n alignas(64) atomic_bool b_turn {false};\n alignas(64) atomic_bool fb_turn {false};\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while (i.load() <= n) {\n while (!f_turn.exchange(false, memory_order_relaxed)) {\n if (i.load(memory_order_relaxed) > n) {\n return;\n }\n std::this_thread::yield();\n }\n printFizz();\n step();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while (i.load() <= n) {\n while (!b_turn.exchange(false, memory_order_relaxed)) {\n if (i.load(memory_order_relaxed) > n) {\n return;\n }\n std::this_thread::yield();\n }\n printBuzz();\n step();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while (i.load() <= n) {\n while (!fb_turn.exchange(false, memory_order_relaxed)) {\n if (i.load(memory_order_relaxed) > n) {\n return;\n }\n std::this_thread::yield();\n }\n printFizzBuzz();\n step();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while (i.load() <= n) {\n while (!n_turn.exchange(false, memory_order_relaxed)) {\n if (i.load(memory_order_relaxed) > n) {\n return;\n }\n std::this_thread::yield();\n }\n printNumber(i.load(memory_order_relaxed));\n step();\n }\n }\n\nprivate:\n void step() {\n int c = i.fetch_add(1) + 1;\n if (c > n) {\n return;\n }\n bool f = (c % 3 == 0);\n bool b = (c % 5 == 0);\n if (f && b) {\n fb_turn.store(true);\n return;\n }\n if (f) {\n f_turn.store(true);\n return;\n }\n if (b) {\n b_turn.store(true);\n return;\n }\n n_turn.store(true);\n }\n};\n``` | 3 | 0 | ['Concurrency', 'C++'] | 3 |
fizz-buzz-multithreaded | C++ using semaphores | c-using-semaphores-by-anshu2-jh4v | \n# Code\n\n#include <semaphore.h>\n\nclass FizzBuzz {\nprivate:\n int n;\n sem_t sem_f, sem_b, sem_fb, sem_i;\n int f_cnt = 0, b_cnt = 0, fb_cnt = 0, | anshu2 | NORMAL | 2022-11-17T02:58:01.135086+00:00 | 2022-11-17T02:58:01.135130+00:00 | 256 | false | \n# Code\n```\n#include <semaphore.h>\n\nclass FizzBuzz {\nprivate:\n int n;\n sem_t sem_f, sem_b, sem_fb, sem_i;\n int f_cnt = 0, b_cnt = 0, fb_cnt = 0, i_cnt = 0;\n int i = 1;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n\n sem_init(&sem_f, 0, 0);\n sem_init(&sem_b, 0, 0);\n sem_init(&sem_fb, 0, 0);\n sem_init(&sem_i, 0, 1);\n\n for (int i = 1; i <= n; ++i) {\n if (i % 3 == 0 && i % 5 == 0) ++fb_cnt;\n else if (i % 3 == 0 && i % 5 != 0) ++f_cnt;\n else if (i % 3 != 0 && i % 5 == 0) ++b_cnt;\n else ++i_cnt;\n }\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while(f_cnt > 0) {\n sem_wait(&sem_f);\n printFizz();\n ++i;\n postSem();\n --f_cnt;\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while(b_cnt > 0) {\n sem_wait(&sem_b);\n printBuzz();\n ++i;\n postSem();\n --b_cnt;\n }\n }\n\n void postSem() {\n if (i % 3 == 0 && i % 5 == 0) sem_post(&sem_fb);\n else if (i % 3 == 0 && i % 5 != 0) sem_post(&sem_f);\n else if (i % 3 != 0 && i % 5 == 0) sem_post(&sem_b);\n else sem_post(&sem_i);\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while(fb_cnt > 0) {\n sem_wait(&sem_fb);\n printFizzBuzz();\n ++i;\n postSem();\n --fb_cnt;\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while(i_cnt > 0) {\n sem_wait(&sem_i);\n printNumber(i);\n ++i;\n postSem();\n --i_cnt;\n }\n }\n};\n``` | 3 | 0 | ['C++'] | 0 |
fizz-buzz-multithreaded | _Fizz Buzz Multithreaded Java - no using any classes java.util.concurrent.* | fizz-buzz-multithreaded-java-no-using-an-sqx9 | I don\'t get what knowledge "1195. Fizz Buzz Multithreaded problem tries to check.\nHow don\'t write multithreaded or concurrent programs on Java?\n\nRuntime: 8 | zazzazzza | NORMAL | 2022-08-01T11:46:56.178295+00:00 | 2022-08-01T11:46:56.178337+00:00 | 734 | false | I don\'t get what knowledge "[1195. Fizz Buzz Multithreaded](https://leetcode.com/problems/fizz-buzz-multithreaded) problem tries to check.\nHow don\'t write multithreaded or concurrent programs on Java?\n\nRuntime: 8 ms, faster than 81.09% of Java online submissions for Fizz Buzz Multithreaded.\nMemory Usage: 41.5 MB, less than 99.03% of Java online submissions for Fizz Buzz Multithreaded.\n```\nclass FizzBuzz { \n private volatile int cursor = 1;\n private int n;\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while (cursor <= n) {\n synchronized (this) {\n if (cursor % 15 != 0 && cursor % 3 == 0 && cursor <= n) {\n printFizz.run();\n cursor++;\n }\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while (cursor <= n) {\n synchronized (this) {\n if (cursor % 15 != 0 && cursor % 5 == 0 && cursor <= n) {\n printBuzz.run();\n cursor++;\n }\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (cursor <= n) {\n synchronized (this) {\n if (cursor % 15 == 0 && cursor <= n) {\n printFizzBuzz.run();\n cursor++;\n }\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while (cursor <= n) {\n synchronized (this) {\n if (cursor % 5 != 0 && cursor % 3 != 0 && cursor <= n) {\n printNumber.accept(cursor);\n cursor++;\n }\n }\n }\n }\n}\n``` | 3 | 0 | ['Java'] | 3 |
fizz-buzz-multithreaded | Python3 | Very Simple solution using Barriers (only) | Beats 72% | python3-very-simple-solution-using-barri-8opp | \nfrom threading import Barrier\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.bar = Barrier(4)\n\n # printFizz() output | thunderVan | NORMAL | 2022-07-23T22:43:56.260928+00:00 | 2022-07-23T22:44:47.062075+00:00 | 1,014 | false | ```\nfrom threading import Barrier\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.bar = Barrier(4)\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n \t\n for i in range(1,self.n+1):\n if i%5!=0 and i%3==0:\n printFizz()\n self.bar.wait()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n \n for i in range(1,self.n+1):\n if i%3!=0 and i %5 ==0:\n printBuzz()\n self.bar.wait()\n \t\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n \n for i in range(1,self.n+1):\n if i%5==0 and i%3==0:\n printFizzBuzz()\n self.bar.wait()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n \n for i in range(1,self.n+1):\n \n if (i % 3) !=0 and (i%5) !=0:\n printNumber(i)\n self.bar.wait()\n\n``` | 3 | 0 | ['Python'] | 1 |
fizz-buzz-multithreaded | Java 5ms Simple Semaphores Solution | java-5ms-simple-semaphores-solution-by-a-cr8y | Few pointers:\n1. Semphore(0) makes some threads locked initially\n2. After every fizz, buzz or fizzBuzz we would always print a number.\n\n\n\nclass FizzBuzz { | amma | NORMAL | 2022-07-07T00:58:48.586659+00:00 | 2022-07-07T00:58:48.586718+00:00 | 388 | false | Few pointers:\n1. Semphore(0) makes some threads locked initially\n2. After every fizz, buzz or fizzBuzz we would always print a number.\n\n\n```\nclass FizzBuzz {\n private int n;\n\n private Semaphore number, fizz , buzz, fizzBuzz;\n \n public FizzBuzz(int n) {\n this.n = n;\n\t\tnumber = new Semaphore(1);\n fizz = new Semaphore(0);\n\t\tbuzz = new Semaphore(0);\n\t\tfizzBuzz = new Semaphore(0);\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for(int i = 3; i<= n; i+=3){\n if (i%5 != 0)\n {\n fizz.acquire();\n printFizz.run();\n number.release();\n }\n }\n \n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for(int i = 5; i<= n; i+=5){\n if (i%3 != 0)\n {\n buzz.acquire();\n printBuzz.run();\n number.release();\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for(int i = 15; i<= n; i+=15){\n \n fizzBuzz.acquire();\n printFizzBuzz.run();\n number.release();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n for(int i=1; i<=n ;i++){\n number.acquire();\n if (i%15 == 0)\n fizzBuzz.release();\n else if ( i % 5 == 0)\n buzz.release();\n else if (i %3 == 0 )\n fizz.release();\n else\n {\n printNumber.accept(i);\n number.release();\n }\n }\n }\n}\n``` | 3 | 0 | ['Java'] | 0 |
fizz-buzz-multithreaded | Java solution, 99% faster using Lock, includes test code | java-solution-99-faster-using-lock-inclu-6uqi | Java solution, faster than 99% Java submisions, also includes the code that I used for tests below.\n\n\nclass FizzBuzz {\n private final int n;\n private | stefancomanita | NORMAL | 2022-03-10T21:45:35.222366+00:00 | 2022-03-10T21:45:35.222396+00:00 | 1,514 | false | Java solution, faster than 99% Java submisions, also includes the code that I used for tests below.\n\n```\nclass FizzBuzz {\n private final int n;\n private int currentValue = 1;\n private final java.util.concurrent.locks.Lock lock = new java.util.concurrent.locks.ReentrantLock();\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n\n while(currentValue <= n) {\n\n lock.lock();\n try {\n if (currentValue <= n && (currentValue % 3 == 0 && currentValue % 5 != 0)) {\n\n printFizz.run();\n currentValue++;\n }\n } finally {\n lock.unlock();\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while(currentValue <= n) {\n\n lock.lock();\n try {\n if (currentValue <= n && (currentValue % 3 != 0 && currentValue % 5 == 0)) {\n\n printBuzz.run();\n currentValue++;\n }\n } finally {\n lock.unlock();\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while(currentValue <= n) {\n\n lock.lock();\n try {\n if (currentValue <= n && (currentValue % 3 == 0 && currentValue % 5 == 0)) {\n\n printFizzBuzz.run();\n currentValue++;\n }\n } finally {\n lock.unlock();\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(java.util.function.IntConsumer printNumber) throws InterruptedException {\n\n while(currentValue <= n) {\n\n lock.lock();\n try {\n if (currentValue <= n && (currentValue % 3 != 0 && currentValue % 5 != 0)) {\n\n printNumber.accept(currentValue);\n currentValue++;\n }\n } finally {\n lock.unlock();\n }\n }\n\n }\n}\n```\n\nCode that I used for testing/debuging\n\n```\n private static void testFizzBuzz() {\n\n\n FizzBuzz fizzBuzz = new FizzBuzz(15);\n\n Runnable fizz = () -> System.out.print("fizz");\n Runnable buzz = () -> System.out.print("buzz");\n Runnable fBuzz = () -> System.out.print("fizzbuzz");\n\n IntConsumer number = System.out::print;\n\n\n new Thread(() -> {\n\n try {\n fizzBuzz.fizz(fizz);\n } catch (InterruptedException e) {\n\n e.printStackTrace();\n\n throw new RuntimeException(e);\n }\n }).start();\n\n new Thread(() -> {\n\n try {\n fizzBuzz.buzz(buzz);\n } catch (InterruptedException e) {\n\n e.printStackTrace();\n\n throw new RuntimeException(e);\n }\n }).start();\n\n new Thread(() -> {\n\n try {\n fizzBuzz.fizzbuzz(fBuzz);\n } catch (InterruptedException e) {\n\n e.printStackTrace();\n\n throw new RuntimeException(e);\n }\n }).start();\n\n new Thread(() -> {\n\n try {\n fizzBuzz.number(number);\n } catch (InterruptedException e) {\n\n e.printStackTrace();\n\n throw new RuntimeException(e);\n }\n }).start();\n }\n``` | 3 | 0 | ['Java'] | 2 |
fizz-buzz-multithreaded | Java using ReentrantLock and Condition | java-using-reentrantlock-and-condition-b-2qje | This is the essentially the same idea taken from Java, using synchronized with short explanation.. Thanks @Hai_dee for the great explanation there.\n\nJava\ncla | cielong | NORMAL | 2022-01-17T03:02:27.252012+00:00 | 2022-01-17T03:02:27.252055+00:00 | 613 | false | This is the essentially the same idea taken from [Java, using synchronized with short explanation.](https://leetcode.com/problems/fizz-buzz-multithreaded/discuss/385395/Java-using-synchronized-with-short-explanation.). Thanks [@Hai_dee](https://leetcode.com/Hai_dee/) for the great explanation there.\n\n```Java\nclass FizzBuzz { \n private final Lock lock = new ReentrantLock();\n private final Condition nextNumber = lock.newCondition();\n \n private final int n;\n private int currentIndex;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.currentIndex = 1;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while (currentIndex <= n) {\n lock.lock();\n try {\n if (currentIndex % 3 != 0 || currentIndex % 5 == 0) {\n nextNumber.await();\n continue;\n }\n\n //System.out.println("fizz " + currentIndex);\n\n printFizz.run();\n currentIndex++;\n\t\t\t\t\n\t\t\t\t// the reason we use signalAll instead of signal because signal may awake the wrong thread\n\t\t\t\t// and incur signal miss\n nextNumber.signalAll();\n } finally {\n lock.unlock();\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while (currentIndex <= n) {\n lock.lock();\n try {\n if (currentIndex % 5 != 0 || currentIndex % 3 == 0) {\n nextNumber.await();\n continue;\n }\n\n //System.out.println("buzz " + currentIndex);\n\n printBuzz.run();\n currentIndex++;\n nextNumber.signalAll();\n } finally {\n lock.unlock();\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (currentIndex <= n) {\n lock.lock();\n \n try {\n if (currentIndex % 15 != 0) {\n nextNumber.await();\n continue;\n }\n //System.out.println("fizzbuzz " + currentIndex);\n\n printFizzBuzz.run();\n currentIndex++;\n nextNumber.signalAll();\n } finally {\n lock.unlock();\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while (currentIndex <= n) {\n lock.lock();\n try {\n if (currentIndex % 3 == 0 || currentIndex % 5 == 0) {\n nextNumber.await();\n continue; \n }\n //System.out.println("number " + currentIndex);\n\n printNumber.accept(currentIndex++);\n nextNumber.signalAll();\n } finally {\n lock.unlock();\n }\n }\n } \n}\n``` | 3 | 0 | ['Java'] | 1 |
fizz-buzz-multithreaded | Java 's semaphore solution's explaination for most multithread problem | java-s-semaphore-solutions-explaination-m0dpd | Overall, a semaphore is a kind of token counter controlled by us (developer). \n\nEach time, when a thread runs acquire() method, it acuqires , and then, immed | laodasb | NORMAL | 2020-12-01T10:59:29.060922+00:00 | 2020-12-22T23:31:59.252272+00:00 | 349 | false | Overall, a semaphore is a kind of token counter controlled by us (developer). \n\nEach time, when a thread runs acquire() method, it acuqires , and then, **immediately consumes** that permit token, which allows the thread to run but also decrease its permit token by one.\n\nBy contrast, if a thread calls its release() method,it will release a permit token, and then can be acquired by others later.\n\nIn conclusion, acquire() makes a decrement of token held by us (developer) and release() makes an increment, once a thread acquire, it can run.\n\nHope it can help.\n```\nimport java.util.concurrent.Semaphore;\nclass FizzBuzz {\n private int n;\n private Semaphore s1,s3,s5,s15;\n public FizzBuzz(int n) {\n this.n = n;\n s1=new Semaphore(1);\n s3=new Semaphore(0);\n s5=new Semaphore(0);\n s15=new Semaphore(0);\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for(int i=3;i<=n;i+=3){\n if(i%5==0) continue;\n s3.acquire();\n printFizz.run();\n s1.release();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for(int i=5;i<=n;i+=5){\n if(i%3==0) continue;\n s5.acquire();\n printBuzz.run();\n s1.release();\n } \n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for(int i=15;i<=n;i+=15){\n s15.acquire();\n printFizzBuzz.run();\n s1.release();\n } \n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n for(int i=1;i<=n;i+=1){\n s1.acquire();\n if(i%15==0){\n s15.release();\n }else if(i%5==0){\n s5.release();\n }else if(i%3==0){\n s3.release();\n }else{\n printNumber.accept(i);\n s1.release();\n }\n } \n }\n}\n``` | 3 | 0 | [] | 0 |
fizz-buzz-multithreaded | Python Solution with Condition Variable | python-solution-with-condition-variable-ap2g1 | The idea is that each of 4 threads tries to print numbers that it\'s responsible for. fizz prints numbers divisible only by 3, buzz prints numbers divisible onl | saulpayne | NORMAL | 2020-05-19T20:57:54.005684+00:00 | 2020-05-19T20:57:54.005736+00:00 | 422 | false | The idea is that each of 4 threads tries to print numbers that it\'s responsible for. ```fizz``` prints numbers divisible only by 3, ```buzz``` prints numbers divisible only by 5, ```fizzbuzz``` prints numbers divisible by 15, and ```number``` prints remaining numbers. But we have to handle order of prints.\n\n```\nfrom threading import Condition\n\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.cv = Condition() # condition variable\n self.n = n #\n self.k = 1 # current number\n\n \n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n i = 3\n while i <= self.n: # iterate over multiples of 3\n with self.cv:\n self.cv.wait_for(lambda: self.k == i) # check if it\'s fizz\'s turn to print\n printFizz()\n self.k += 1\n self.cv.notify_all() # notify other threads that self.k has been changed and they can check their conditions (other threads are blocked in their wait_for statements)\n i += 3\n if i % 5 == 0: # skip, because \'i\' is divisible by 15 and it should be handled by \'fizzbuzz\'\n i += 3\n \n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n i = 5\n while i <= self.n: # iterate over multiples of 5\n with self.cv:\n self.cv.wait_for(lambda: self.k == i) # check if it\'s buzz\'s turn to print\n printBuzz()\n self.k += 1\n self.cv.notify_all() # notify other threads that self.k has been changed and they can check their conditions (other threads are blocked in their wait_for statements)\n i += 5\n if i % 3 == 0: # skip, because \'i\' is divisible by 15 and it should be handled by \'fizzbuzz\'\n i += 5\n \t\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for i in range(15, self.n + 1, 15): # iterate over multiples of 15\n with self.cv:\n self.cv.wait_for(lambda: self.k == i) # check if it\'s fizzbuzz\'s turn to print\n printFizzBuzz()\n self.k += 1\n self.cv.notify_all() # notify other threads that self.k has been changed and they can check their conditions (other threads are blocked in their wait_for statements)\n\n \n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n i = 1\n while i <= self.n:\n if i % 3 and i % 5: # consider only numbers that are not divisible by 3 and 5\n with self.cv:\n self.cv.wait_for(lambda: self.k == i) # check if it\'s number\'s turn to print\n printNumber(self.k)\n self.k += 1\n self.cv.notify_all() # notify other threads that self.k has been changed and they can check their conditions (other threads are blocked in their wait_for statements)\n i += 1\n \n\t\t\t\n```\n\nNumbers printed by 4 threads are mutually exclusive; therefore, we can be sure that at each change of ```k``` only one ```print``` is called. Also, union of numbers of each thread gives all numbers in the range ```[1, n]```, so we can be sure that deadlock won\'t occur.\n | 3 | 0 | [] | 1 |
fizz-buzz-multithreaded | c# faster than 94% (44ms) using AutoResetEvent | c-faster-than-94-44ms-using-autoreseteve-9c5t | csharp\npublic class FizzBuzz\n\t{\n private readonly AutoResetEvent fizz = new AutoResetEvent(false);\n\t\tprivate readonly AutoResetEvent buzz = new Au | giometrix | NORMAL | 2020-04-24T17:07:13.092460+00:00 | 2020-04-24T17:07:13.092513+00:00 | 404 | false | ```csharp\npublic class FizzBuzz\n\t{\n private readonly AutoResetEvent fizz = new AutoResetEvent(false);\n\t\tprivate readonly AutoResetEvent buzz = new AutoResetEvent(false);\n\t\tprivate readonly AutoResetEvent buzzComplete = new AutoResetEvent(false);\n\t\tprivate readonly AutoResetEvent fizzbuzz = new AutoResetEvent(false);\n\t\tprivate readonly AutoResetEvent fizzBuzzComplete = new AutoResetEvent(false);\n\t\tprivate readonly AutoResetEvent fizzComplete = new AutoResetEvent(false);\n\t\t\n private readonly int n;\n private int curr = 1;\n\n\t\tpublic FizzBuzz(int n)\n\t\t{\n\t\t\tthis.n = n;\n\t\t}\n\n\t\t// printFizz() outputs "fizz".\n\t\tpublic void Fizz(Action printFizz)\n\t\t{\n\t\t\twhile (fizz.WaitOne() && curr <= n)\n\t\t\t{\n\t\t\t\t//fizz.WaitOne();\n\t\t\t\tprintFizz();\n\t\t\t\tfizzComplete.Set();\n\t\t\t}\n\t\t}\n\n\t\t// printBuzzz() outputs "buzz".\n\t\tpublic void Buzz(Action printBuzz)\n\t\t{\n\t\t\twhile (buzz.WaitOne() && curr <= n)\n\t\t\t{\n\t\t\t\tprintBuzz();\n\t\t\t\tbuzzComplete.Set();\n\t\t\t}\n\t\t}\n\n\t\t// printFizzBuzz() outputs "fizzbuzz".\n\t\tpublic void Fizzbuzz(Action printFizzBuzz)\n\t\t{\n\t\t\twhile (fizzbuzz.WaitOne() && curr <= n)\n\t\t\t{\n\t\t\t\tprintFizzBuzz();\n\t\t\t\tfizzBuzzComplete.Set();\n\t\t\t}\n\t\t}\n\n\t\t// printNumber(x) outputs "x", where x is an integer.\n\t\tpublic void Number(Action<int> printNumber)\n\t\t{\n\t\t\tfor (; curr <= n; curr++)\n\t\t\t\tif (curr % 3 == 0 && curr % 5 == 0)\n\t\t\t\t{\n\t\t\t\t\tfizzbuzz.Set();\n\t\t\t\t\tfizzBuzzComplete.WaitOne();\n\t\t\t\t}\n\t\t\t\telse if (curr % 3 == 0 && curr % 5 > 0)\n\t\t\t\t{\n\t\t\t\t\tfizz.Set();\n\t\t\t\t\tfizzComplete.WaitOne();\n\t\t\t\t}\n\t\t\t\telse if (curr % 3 > 0 && curr % 5 == 0)\n\t\t\t\t{\n\t\t\t\t\tbuzz.Set();\n\t\t\t\t\tbuzzComplete.WaitOne();\n\t\t\t\t}\n\t\t\t\telse\n\t\t\t\t{\n\t\t\t\t\tprintNumber(curr);\n\t\t\t\t}\n\n\t\t\tfizz.Set();\n\t\t\tbuzz.Set();\n\t\t\tfizzbuzz.Set();\n\t\t}\n\t}\n\t\n\t``` | 3 | 0 | [] | 0 |
fizz-buzz-multithreaded | Python3 using Lock, 96% | python3-using-lock-96-by-nightybear-l8u0 | Attached is the solution using Lock, welcome to discuss.\n\npython\n\nfrom threading import Lock\n\nclass FizzBuzz:\n def __init__(self, n: int):\n se | nightybear | NORMAL | 2019-11-13T01:31:04.023876+00:00 | 2019-11-13T01:31:04.023954+00:00 | 922 | false | Attached is the solution using Lock, welcome to discuss.\n\n```python\n\nfrom threading import Lock\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.l1 = [Lock() for _ in range(3)]\n self.l2 = [Lock() for _ in range(3)]\n \n # lock all the locks\n for i in range(3):\n self.l1[i].acquire()\n self.l2[i].acquire()\n \n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n \tfor val in range(1, self.n+1):\n if val % 3 == 0 and val % 5:\n self.l1[0].acquire()\n printFizz()\n self.l2[0].release()\n \n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n \tfor val in range(1, self.n+1):\n if val % 5 == 0 and val % 3:\n self.l1[1].acquire()\n printBuzz()\n self.l2[1].release()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n \tfor val in range(1, self.n+1):\n if val % 3 == 0 and val % 5 == 0:\n self.l1[2].acquire()\n printFizzBuzz()\n self.l2[2].release()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n \tfor val in range(1, self.n+1):\n if val % 3 and val % 5:\n printNumber(val)\n elif val % 3 == 0 and val % 5:\n # fizz\n self.l1[0].release()\n self.l2[0].acquire()\n \n elif val % 5 == 0 and val % 3:\n # Buzz\n self.l1[1].release()\n self.l2[1].acquire()\n else:\n # FizzBuzz\n self.l1[2].release()\n self.l2[2].acquire()\n\n``` | 3 | 1 | ['Python3'] | 0 |
fizz-buzz-multithreaded | unique_lock and condition variable C++ | unique_lock-and-condition-variable-c-by-dikad | class FizzBuzz {\nprivate:\n int n;\n mutex mtx;\n condition_variable cv;\n int tmp; bool a;\n \npublic:\n FizzBuzz(int n) {\n this->n | _CodeSlayer_ | NORMAL | 2019-10-28T05:03:18.992992+00:00 | 2019-10-28T05:03:18.993038+00:00 | 594 | false | class FizzBuzz {\nprivate:\n int n;\n mutex mtx;\n condition_variable cv;\n int tmp; bool a;\n \npublic:\n FizzBuzz(int n) {\n this->n = n; this->tmp=1;//this->tmp2=0;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while(tmp<=n) {\n { \n // a = ; //cout<<a ;\n unique_lock<mutex> lk(mtx);\n cv.wait(lk, [this]() {return (((tmp%5)!=0)&&(((tmp%3)==0))); }); cout<<"fizz";\n printFizz() ;\n tmp++; \n }\n cv.notify_all();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while(tmp<=n) {\n {\n unique_lock<mutex> lk(mtx);\n cv.wait(lk, [this]() { return ((tmp%3)!=0)&&(((tmp%5)==0)) ; });\n cout<<"buzz" ;\n printBuzz() ;\n tmp++; \n }\n cv.notify_all();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while(tmp<=n) {\n {\n unique_lock<mutex> lk(mtx);\n cv.wait(lk, [this]() { return (((tmp%5)==0)&&(((tmp%3)==0))); }); cout<<"fizz-Buzz";\n printFizzBuzz() ; //printFizz() ;\n tmp++; \n }\n cv.notify_all();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while(tmp<=n) {\n {\n unique_lock<mutex> lk(mtx);\n cv.wait(lk, [this]() { return (((tmp%5)!=0)&&(((tmp%3)!=0))); }); cout<<tmp;\n printNumber(tmp) ;\n tmp++; \n }\n cv.notify_all();\n }\n }\n};\n\n\nSomeone please help me out with the bug :( | 3 | 0 | ['C'] | 1 |
fizz-buzz-multithreaded | Intuitive Java Solution With Explanation | intuitive-java-solution-with-explanation-u1uw | Idea\nUse Guarded Blocks and the logic is similar to producer-consumer problem from\nhttps://docs.oracle.com/javase/tutorial/essential/concurrency/guardmeth.htm | naveen_kothamasu | NORMAL | 2019-10-06T01:11:48.496803+00:00 | 2019-10-06T01:11:48.496855+00:00 | 481 | false | **Idea**\nUse `Guarded Blocks` and the logic is similar to producer-consumer problem from\nhttps://docs.oracle.com/javase/tutorial/essential/concurrency/guardmeth.html\n\n```\nclass FizzBuzz {\n private int n;\n private int counter = 1;\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public synchronized void fizz(Runnable printFizz) throws InterruptedException {\n while(true){\n while(counter <= n && (counter % 3 != 0 || counter % 5 == 0)){\n wait();\n }\n if(counter > n) break;\n printFizz.run();\n ++counter;\n notifyAll();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public synchronized void buzz(Runnable printBuzz) throws InterruptedException {\n while(true){\n while(counter <= n && (counter % 5 != 0 || counter % 3 == 0)){\n wait();\n }\n if(counter > n) break;\n printBuzz.run();\n ++counter;\n notifyAll();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public synchronized void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while(true){\n while(counter <= n && !(counter % 3 == 0 && counter % 5 == 0)){\n wait();\n }\n if(counter > n) break;\n printFizzBuzz.run();\n ++counter;\n notifyAll();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public synchronized void number(IntConsumer printNumber) throws InterruptedException {\n while(true){\n while(counter <= n && (counter % 3 == 0 || counter % 5 == 0)){\n wait();\n }\n if(counter > n) break;\n printNumber.accept(counter);\n ++counter;\n notifyAll();\n }\n }\n}\n``` | 3 | 0 | [] | 1 |
fizz-buzz-multithreaded | C# 52 ms, barrier | c-52-ms-barrier-by-csuporj-fwbn | \tpublic class FizzBuzz\n {\n private int n;\n private int i;\n private System.Threading.Barrier barrier;\n\n public FizzBuzz(int | csuporj | NORMAL | 2019-09-22T00:11:50.675205+00:00 | 2019-09-22T00:16:10.833396+00:00 | 473 | false | \tpublic class FizzBuzz\n {\n private int n;\n private int i;\n private System.Threading.Barrier barrier;\n\n public FizzBuzz(int n)\n {\n this.n = n;\n barrier = new System.Threading.Barrier(4);\n }\n\n // printFizz() outputs "fizz".\n public void Fizz(Action printFizz)\n {\n while (true)\n {\n barrier.SignalAndWait();\n if (i > n)\n {\n break;\n }\n if (i % 3 == 0 && i % 5 != 0)\n {\n printFizz();\n }\n barrier.SignalAndWait();\n }\n }\n\n // printBuzzz() outputs "buzz".\n public void Buzz(Action printBuzz)\n {\n while (true)\n {\n barrier.SignalAndWait();\n if (i > n)\n {\n break;\n }\n if (i % 5 == 0 && i % 3 != 0)\n {\n printBuzz();\n }\n barrier.SignalAndWait();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n public void Fizzbuzz(Action printFizzBuzz)\n {\n while (true)\n {\n barrier.SignalAndWait();\n if (i > n)\n {\n break;\n }\n if (i % 15 == 0)\n {\n printFizzBuzz();\n }\n barrier.SignalAndWait();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n public void Number(Action<int> printNumber)\n {\n while (true)\n {\n i++;\n barrier.SignalAndWait();\n if (i > n)\n {\n break;\n }\n if (i % 3 != 0 && i % 5 != 0)\n {\n printNumber(i);\n }\n barrier.SignalAndWait();\n }\n }\n }\n | 3 | 0 | [] | 2 |
fizz-buzz-multithreaded | Simple std::barrier solution | simple-stdbarrier-solution-by-user4153oo-t7gv | \n# Code\ncpp []\n#include <barrier>\n\nclass FizzBuzz {\nprivate:\n int n;\n std::barrier<> sync_point{ 4 };\npublic:\n FizzBuzz(int n) {\n thi | user4153oO | NORMAL | 2024-10-15T19:12:28.058985+00:00 | 2024-10-15T19:12:28.059009+00:00 | 225 | false | \n# Code\n```cpp []\n#include <barrier>\n\nclass FizzBuzz {\nprivate:\n int n;\n std::barrier<> sync_point{ 4 };\npublic:\n FizzBuzz(int n) {\n this->n = n;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n for (unsigned i = 1; i <= n; ++i)\n {\n if ((i % 3 == 0) && (i % 5 != 0)) {\n printFizz();\n }\n sync_point.arrive_and_wait();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n for (unsigned i = 1; i <= n; ++i)\n {\n if ((i % 3 != 0) && (i % 5 == 0)) {\n printBuzz();\n }\n sync_point.arrive_and_wait();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n for (unsigned i = 1; i <= n; ++i)\n {\n if ((i % 3 == 0) && (i % 5 == 0)) {\n printFizzBuzz();\n }\n sync_point.arrive_and_wait();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n for (unsigned i = 1; i <= n; ++i)\n {\n if ((i % 3 != 0) && (i % 5 != 0)) {\n printNumber(i);\n }\n sync_point.arrive_and_wait();\n }\n }\n};\n``` | 2 | 0 | ['C++'] | 1 |
fizz-buzz-multithreaded | Java - Sync-step with Phaser | java-sync-step-with-phaser-by-give_me_th-o6mv | Intuition\nThe result for a given number n is deterministic, and only 1 of the operations will produce output. The shared resource is essentially the iteration | give_me_the_formuoli | NORMAL | 2024-05-02T17:00:45.195422+00:00 | 2024-05-02T17:00:45.195444+00:00 | 396 | false | # Intuition\nThe result for a given number `n` is deterministic, and only 1 of the operations will produce output. The shared resource is essentially the iteration order, so we produce synchronization around that. Additionally, there is only a single result for each value `n`, so each call/thread can independently determine if it should call it\'s input function. Using a barrier allows the threads to be parked allowing for other work to be scheduled on them.\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n- Each thread independently determines if it should call it\'s `Runnable`/`IntConsumer`. If it is supposed to call it, it calls it. We are guaranteed exactly 1 call per "round"\n- Each thread parks at the `Phaser`, awaiting for the others\n- Only when all threads arrive to the `Phaser`, do they sync-step and advance to the next number.\n\n# Complexity\n- Time complexity: $O(n)$ - each function iterates $n$ times\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: $O(1)$ - a single, shared `Phaser` instance\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass FizzBuzz {\n private final int n;\n private final Phaser phaser = new Phaser(4);\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n var shouldPrint = i % 3 == 0 && i % 5 != 0;\n if (shouldPrint) printFizz.run();\n phaser.arriveAndAwaitAdvance();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n var shouldPrint = i % 5 == 0 && i % 3 != 0;\n if (shouldPrint) printBuzz.run();\n phaser.arriveAndAwaitAdvance();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n var shouldPrint = i % 5 == 0 && i % 3 == 0;\n if (shouldPrint) printFizzBuzz.run();\n phaser.arriveAndAwaitAdvance();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n var shouldPrint = i % 3 != 0 && i % 5 != 0;\n if (shouldPrint) printNumber.accept(i);\n phaser.arriveAndAwaitAdvance();\n }\n }\n}\n``` | 2 | 0 | ['Java'] | 0 |
fizz-buzz-multithreaded | Best Java Solution || Beats 100% | best-java-solution-beats-100-by-ravikuma-5idz | Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time | ravikumar50 | NORMAL | 2023-09-28T09:30:24.215074+00:00 | 2023-09-28T09:30:24.215095+00:00 | 1,308 | false | # Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass FizzBuzz {\n // taken help\n \n private int n;\n private int i;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.i = 1;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%3==0 && i%5!=0) {\n printFizz.run();\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%3!=0 && i%5==0) {\n printBuzz.run();\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%15==0) {\n printFizzBuzz.run();\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n synchronized (this) {\n while (i<=n) {\n if (i%3!=0 && i%5!=0) {\n printNumber.accept(i);\n i+=1;\n notifyAll(); \n } else {\n wait();\n }\n }\n }\n }\n}\n``` | 2 | 0 | ['Java'] | 1 |
fizz-buzz-multithreaded | C++ EASY SOLUTION | c-easy-solution-by-arpiii_7474-gatw | Code\n\nclass FizzBuzz {\nprivate:\n int n;\n mutex m;\n condition_variable cv;\n int i;\npublic:\n FizzBuzz(int n) {\n this->n = n;\n | arpiii_7474 | NORMAL | 2023-09-26T05:21:46.909746+00:00 | 2023-09-26T05:21:46.909770+00:00 | 677 | false | # Code\n```\nclass FizzBuzz {\nprivate:\n int n;\n mutex m;\n condition_variable cv;\n int i;\npublic:\n FizzBuzz(int n) {\n this->n = n;\n this->i=1;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while(i<=n){\n unique_lock<mutex> lock(m);\n while(i<=n && !((i%3==0) && (i%5!=0))) cv.wait(lock);\n if(i<=n){\n printFizz();\n i++;\n }\n cv.notify_all();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while(i<=n){\n unique_lock<mutex> lock(m);\n while(i<=n && !((i%3!=0) && (i%5==0))) cv.wait(lock);\n if(i<=n){\n printBuzz();\n i++;\n }\n cv.notify_all();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while(i<=n){\n unique_lock<mutex> lock(m);\n while(i<=n && !((i%3==0) && (i%5==0))) cv.wait(lock);\n if(i<=n){\n printFizzBuzz();\n i++;\n }\n cv.notify_all();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while(i<=n){\n unique_lock<mutex> lock(m);\n while(i<=n && !((i%3!=0) && (i%5!=0))) cv.wait(lock);\n if(i<=n){\n printNumber(i);\n i++;\n }\n cv.notify_all();\n }\n }\n};\n``` | 2 | 0 | ['C++'] | 0 |
fizz-buzz-multithreaded | Trivial C++ beats 100% | trivial-c-beats-100-by-shoumikhin-khfl | \n\nclass FizzBuzz {\nprivate:\n int n;\n atomic_int i{1};\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n }\n\n // printFizz() outputs "f | shoumikhin | NORMAL | 2023-02-01T03:50:27.350798+00:00 | 2023-02-01T03:50:27.350845+00:00 | 301 | false | \n```\nclass FizzBuzz {\nprivate:\n int n;\n atomic_int i{1};\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n for (auto ii = i.load(); ii <= n; ii = i.load()) {\n if (ii % 3 == 0 && ii % 5 != 0) {\n printFizz();\n i.store(ii + 1);\n }\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n for (auto ii = i.load(); ii <= n; ii = i.load()) {\n if (ii % 5 == 0 && ii % 3 != 0) {\n printBuzz();\n i.store(ii + 1);\n }\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n for (auto ii = i.load(); ii <= n; ii = i.load()) {\n if (ii % 3 == 0 && ii % 5 == 0) {\n printFizzBuzz();\n i.store(ii + 1);\n }\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n for (auto ii = i.load(); ii <= n; ii = i.load()) {\n if (ii % 3 != 0 && ii % 5 != 0) {\n printNumber(ii);\n i.store(ii + 1);\n }\n }\n }\n};\n``` | 2 | 0 | ['C++'] | 1 |
fizz-buzz-multithreaded | Python Barrier Solution | python-barrier-solution-by-christopher71-x80v | Straight forward simple solution.\n\nAll 4 threads work on 1 iteration the loop together concurrently, then step together after all have reached.\n\n```\nfrom t | christopher71 | NORMAL | 2022-12-05T10:13:37.382238+00:00 | 2022-12-05T10:13:37.382276+00:00 | 355 | false | Straight forward simple solution.\n\nAll 4 threads work on 1 iteration the loop together concurrently, then step together after all have reached.\n\n```\nfrom threading import Barrier\n\nbarrier = Barrier(4)\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n + 1\n\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 == 0 and cur % 5 != 0:\n printFizz()\n\n barrier.wait()\n\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 != 0 and cur % 5 == 0:\n printBuzz()\n\n barrier.wait()\n\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 == 0 and cur % 5 == 0:\n printFizzBuzz()\n\n barrier.wait()\n\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for cur in range(1, self.n):\n if cur % 3 != 0 and cur % 5 != 0:\n printNumber(cur)\n\n barrier.wait() | 2 | 0 | [] | 1 |
fizz-buzz-multithreaded | C++ using mutex, condition_variable, and unique_lock with Core Guideline annotations | c-using-mutex-condition_variable-and-uni-12ka | I added notes and links to the excellent C++ Core Guidelines section on Concurrency.\n\n\nclass FizzBuzz {\npublic:\n explicit FizzBuzz(int n)\n : n(n | user6040iN | NORMAL | 2022-09-08T17:31:19.513874+00:00 | 2022-09-08T17:31:19.513922+00:00 | 584 | false | I added notes and links to the excellent [C++ Core Guidelines section on Concurrency](https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#SScp-con).\n\n```\nclass FizzBuzz {\npublic:\n explicit FizzBuzz(int n)\n : n(n), i(1), mutex(), condition()\n {\n }\n\n // printFizz() outputs "fizz".\n void fizz(std::function<void()> printFizz)\n {\n auto predicate = [](int v) { return (v % 3 == 0) && (v % 5 != 0); };\n auto printer = [printFizz](int) { printFizz(); };\n run(printer, predicate);\n }\n\n // printBuzz() outputs "buzz".\n void buzz(std::function<void()> printBuzz)\n {\n auto predicate = [](int v) { return (v % 3 != 0) && (v % 5 == 0); };\n auto printer = [printBuzz](int) { printBuzz(); };\n run(printer, predicate);\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n void fizzbuzz(std::function<void()> printFizzBuzz)\n {\n auto predicate = [](int v) { return (v % 3 == 0) && (v % 5 == 0); };\n auto printer = [printFizzBuzz](int) { printFizzBuzz(); };\n run(printer, predicate);\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(std::function<void(int)> printNumber)\n {\n auto predicate = [](int v) { return (v % 3 != 0) && (v % 5 != 0); };\n run(printNumber, predicate);\n }\n\nprivate:\n int n;\n int i;\n std::mutex mutex;\n std::condition_variable condition;\n\n // Thread function, do it once to make sure we have uniform behavior\n template <typename Printer, typename Predicate>\n void run(Printer printer, Predicate predicate)\n {\n for (;;) {\n int v = 0;\n {\n // CP.20: Use RAII, never plain lock()/unlock()\n // https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#cp20-use-raii-never-plain-lockunlock\n std::unique_lock<std::mutex> lock(mutex);\n\n // Wait until predicate is satisfied or we are finished\n // CP.42: Don\'t wait without a condition\n // https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#cp42-dont-wait-without-a-condition\n condition.wait(lock, [this, predicate]() {\n return (i > n) || predicate(i);\n });\n\n if (i > n) {\n break;\n }\n\n v = i;\n }\n\n // CP.22: Never call unknown code while holding a lock (e.g., a\n // callback)\n // https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#cp22-never-call-unknown-code-while-holding-a-lock-eg-a-callback\n printer(v);\n\n {\n std::unique_lock<std::mutex> lock(mutex);\n i++;\n }\n\n // We called our printer, allow the other threads to take their turn\n condition.notify_all();\n }\n }\n};\n``` | 2 | 0 | ['C'] | 0 |
fizz-buzz-multithreaded | Efficient Java Solution using Semaphore | efficient-java-solution-using-semaphore-98azi | \nclass FizzBuzz {\n private int n;\n private int current;\n private int fizzBuzzTotal;\n private int fizzTotal;\n private int buzzTotal;\n pr | HYRFAL | NORMAL | 2022-05-07T16:41:14.780270+00:00 | 2022-05-07T16:41:14.780314+00:00 | 374 | false | ```\nclass FizzBuzz {\n private int n;\n private int current;\n private int fizzBuzzTotal;\n private int fizzTotal;\n private int buzzTotal;\n private int numTotal;\n private Semaphore fizzBuzzSem = new Semaphore(0);\n private Semaphore fizzSem = new Semaphore(0);\n private Semaphore buzzSem = new Semaphore(0);\n private Semaphore numSem = new Semaphore(1);\n\n\n public FizzBuzz(int n) {\n this.n = n;\n this.current = 1;\n // figure out how many total times each thing should print\n this.fizzBuzzTotal = n/15;\n this.fizzTotal = n/3 - fizzBuzzTotal;\n this.buzzTotal = n/5 - fizzBuzzTotal;\n this.numTotal = n - fizzTotal - buzzTotal - fizzBuzzTotal;\n\n }\n\n private void signalNext() {\n current++;\n if (current % 15 == 0) {\n fizzBuzzSem.release();\n } else if (current % 3 == 0) {\n fizzSem.release();\n } else if (current % 5 == 0) {\n buzzSem.release();\n } else {\n numSem.release();\n }\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for (int i = 0; i < fizzTotal; i++) {\n fizzSem.acquire();\n printFizz.run();\n signalNext();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for (int i = 0; i < buzzTotal; i++) {\n buzzSem.acquire();\n printBuzz.run();\n signalNext();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for (int i = 0; i < fizzBuzzTotal; i++) {\n fizzBuzzSem.acquire();\n printFizzBuzz.run();\n signalNext();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n int num = 1;\n for (int i = 0; i < numTotal; i++) {\n numSem.acquire();\n printNumber.accept(num);\n // find the next number\n num++;\n while (num % 3 == 0 || num % 5 == 0) {\n num++;\n }\n signalNext();\n }\n }\n}\n``` | 2 | 0 | [] | 1 |
fizz-buzz-multithreaded | Java 3 solutions | java-3-solutions-by-mypanacea-3u5x | Semaphors\n\n\npublic class Solution1195 {\n\n\tprivate int n;\n\n\tSemaphore fizz = new Semaphore(0);\n\n\tSemaphore buzz = new Semaphore(0);\n\n\tSemaphore fi | mypanacea | NORMAL | 2022-02-15T21:26:04.423763+00:00 | 2022-02-15T21:27:11.120418+00:00 | 326 | false | Semaphors\n\n```\npublic class Solution1195 {\n\n\tprivate int n;\n\n\tSemaphore fizz = new Semaphore(0);\n\n\tSemaphore buzz = new Semaphore(0);\n\n\tSemaphore fizzbuzz = new Semaphore(0);\n\n\tSemaphore number = new Semaphore(1);\n\n\tprivate int count;\n\n\tpublic Solution1195(int n) {\n\t\tthis.n = n;\n\t\tthis.count = 1;\n\t}\n\n\tpublic void fizz(Runnable printFizz) throws InterruptedException {\n\t\twhile (count <= n) {\n\t\t\tif (count % 3 == 0 && count % 5 != 0) {\n\t\t\t\tfizz.acquire();\n\t\t\t\tprintFizz.run();\n\t\t\t\tcount++;\n\t\t\t\treleaseSemaphore(count);\n\t\t\t}\n\t\t}\n\t}\n\n\tpublic void buzz(Runnable printBuzz) throws InterruptedException {\n\t\twhile (count <= n) {\n\t\t\tif (count % 5 == 0 && count % 3 != 0) {\n\t\t\t\tbuzz.acquire();\n\t\t\t\tprintBuzz.run();\n\t\t\t\tcount++;\n\t\t\t\treleaseSemaphore(count);\n\t\t\t}\n\t\t}\n\t}\n\n\tpublic void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n\t\twhile (count <= n) {\n\t\t\tif (count % 15 == 0) {\n\t\t\t\tfizzbuzz.acquire();\n\t\t\t\tprintFizzBuzz.run();\n\t\t\t\tcount++;\n\t\t\t\treleaseSemaphore(count);\n\t\t\t}\n\t\t}\n\t}\n\n\tpublic void number(IntConsumer printNumber) throws InterruptedException {\n\t\twhile (count <= n) {\n\t\t\tif (count % 5 != 0 && count % 3 != 0) {\n\t\t\t\tnumber.acquire();\n\t\t\t\tprintNumber.accept(count);\n\t\t\t\tcount++;\n\t\t\t\treleaseSemaphore(count);\n\t\t\t}\n\t\t}\n\t}\n\n\tprivate void releaseSemaphore(final int i) {\n\t\tif (i % 15 == 0) {\n\t\t\tfizzbuzz.release();\n\t\t\treturn;\n\t\t}\n\t\tif (i % 3 == 0) {\n\t\t\tfizz.release();\n\t\t\treturn;\n\t\t}\n\t\tif (i % 5 == 0) {\n\t\t\tbuzz.release();\n\t\t\treturn;\n\t\t}\n\t\tnumber.release();\n\t}\n}\n\n```\nWait-notify\n\n```\npublic class Solution1195v2 {\n\n\tprivate final int n;\n\n\tprivate int count = 1;\n\n\tpublic Solution1195v2(int n) {\n\t\tthis.n = n;\n\t}\n\n\t// printFizz.run() outputs "fizz".\n\tpublic void fizz(Runnable printFizz) throws InterruptedException {\n\t\tcheckAndPrint(printFizz, x -> x % 3 == 0 && x % 5 != 0);\n\t}\n\n\t// printBuzz.run() outputs "buzz".\n\tpublic void buzz(Runnable printBuzz) throws InterruptedException {\n\t\tcheckAndPrint(printBuzz, x -> x % 5 == 0 && x % 3 != 0);\n\t}\n\n\t// printFizzBuzz.run() outputs "fizzbuzz".\n\tpublic void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n\t\tcheckAndPrint(printFizzBuzz, x -> x % 15 == 0);\n\t}\n\n\t// printNumber.accept(x) outputs "x", where x is an integer.\n\tpublic void number(IntConsumer printNumber) throws InterruptedException {\n\t\tcheckAndPrint(() -> printNumber.accept(count), x -> x % 3 != 0 && x % 5 != 0);\n\t}\n\n\tprivate synchronized void checkAndPrint(final Runnable runnable, final IntPredicate predicate) throws InterruptedException {\n\t\twhile (count <= n) {\n\t\t\tif (predicate.test(count)) {\n\t\t\t\trunnable.run();\n\t\t\t\tcount++;\n\t\t\t\tnotifyAll();\n\t\t\t} else {\n\t\t\t\twait();\n\t\t\t}\n\t\t}\n\t}\n}\n```\n\nAtomicInteger\n\n```\npublic class Solution1195v3 {\n\n\tprivate final AtomicInteger count = new AtomicInteger(1);\n\n\tprivate final int n;\n\n\tpublic Solution1195v3(int n) {\n\t\tthis.n = n;\n\t}\n\n\t// printFizz.run() outputs "fizz".\n\tpublic void fizz(Runnable printFizz) throws InterruptedException {\n\t\tint i;\n\t\twhile ((i = count.get()) <= n) {\n\t\t\tif (i % 3 == 0 && i % 5 != 0) {\n\t\t\t\tprintFizz.run();\n\t\t\t\tcount.compareAndSet(i, i + 1);\n\t\t\t}\n\t\t}\n\t}\n\n\t// printBuzz.run() outputs "buzz".\n\tpublic void buzz(Runnable printBuzz) throws InterruptedException {\n\t\tint i;\n\t\twhile ((i = count.get()) <= n) {\n\t\t\tcount.get();\n\t\t\tif (i % 5 == 0 && i % 3 != 0) {\n\t\t\t\tprintBuzz.run();\n\t\t\t\tcount.compareAndSet(i, i + 1);\n\t\t\t}\n\t\t}\n\t}\n\n\t// printFizzBuzz.run() outputs "fizzbuzz".\n\tpublic void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n\t\tint i;\n\t\twhile ((i = count.get()) <= n) {\n\t\t\tif (i % 15 == 0) {\n\t\t\t\tprintFizzBuzz.run();\n\t\t\t\tcount.compareAndSet(i, i + 1);\n\t\t\t}\n\t\t}\n\t}\n\n\t// printNumber.accept(x) outputs "x", where x is an integer.\n\tpublic void number(IntConsumer printNumber) throws InterruptedException {\n\t\tint i;\n\t\twhile ((i = count.get()) <= n) {\n\t\t\tif (i % 5 != 0 && i % 3 != 0) {\n\t\t\t\tprintNumber.accept(i);\n\t\t\t\tcount.compareAndSet(i, i + 1);\n\t\t\t}\n\t\t}\n\t}\n}\n```\n | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | [Java] Poor Coder's Concurrency - no lock, mutex, semaphore, or other nonsense | java-poor-coders-concurrency-no-lock-mut-4h12 | ```\n// Is this a solution that respects the electricty costs of slamming every thread every millisecond? No.\n// This bad boy is, however, faster than 98.88% o | mikedupuis | NORMAL | 2021-12-16T06:56:25.391461+00:00 | 2021-12-16T07:00:51.278442+00:00 | 374 | false | ```\n// Is this a solution that respects the electricty costs of slamming every thread every millisecond? No.\n// This bad boy is, however, faster than 98.88% of other Java submissions as of 12/16/2021.\n// This is poor coder\'s concurrency, where we need not worry about fancy semaphores, mutexes, locks, etc.\n// Fair warning: if you implement this in a coding interview, you will likely face some... concerned looks.\nclass FizzBuzz {\n private int n;\n \n // The value being printed, fizzed, buzzed, or fizzbuzzed\n int value = 1;\n \n // Whose turn is it?\n int turn = 0;\n \n // Turn sequence, works nicely because fizzbuzz has a cycle length of 15\n // Yes, an enum would be nicer, don\'t @ me\n // 0 - number\n // 1 - fizz\n // 2 - buzz\n // 3 - fizzbuzz\n int turns[] = {\n 0, 0, 1, 0, 2,\n 1, 0, 0, 1, 2,\n 0, 1, 0, 0, 3\n };\n \n // Iterate through turn sequence and increment value\n void nextTurn() {\n turn = (turn + 1)% 15;\n value++;\n }\n \n boolean numTurn() {\n return turns[turn] == 0;\n }\n \n boolean fizzTurn() {\n return turns[turn] == 1;\n }\n \n boolean buzzTurn() {\n return turns[turn] == 2;\n }\n \n boolean fizzBuzzTurn() {\n return turns[turn] == 3;\n }\n \n boolean done() {\n return value == n + 1;\n }\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while (true) {\n if (done()) {\n return;\n }\n \n if (!fizzTurn()) {\n Thread.sleep(1);\n continue;\n }\n \n printFizz.run();\n nextTurn();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while (true) {\n if (done()) {\n return;\n }\n \n if (!buzzTurn()) {\n Thread.sleep(1);\n continue;\n }\n \n printBuzz.run();\n nextTurn();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (true) {\n if (done()) {\n return;\n }\n \n if (!fizzBuzzTurn()) {\n Thread.sleep(1);\n continue;\n }\n \n printFizzBuzz.run();\n nextTurn();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while (true) {\n if (done()) {\n return;\n }\n \n if (!numTurn()) {\n Thread.sleep(1);\n continue;\n }\n \n printNumber.accept(value);\n nextTurn();\n } \n }\n} | 2 | 0 | ['Java'] | 0 |
fizz-buzz-multithreaded | Java Synchronized, very easy to understand and implement, faster than 99% | java-synchronized-very-easy-to-understan-zzou | \nimport java.util.function.Function;\nimport java.util.function.IntConsumer;\n\nclass FizzBuzz {\n private int n;\n private int i;\n\n public FizzBuzz | quandang2002 | NORMAL | 2021-12-05T06:06:17.172692+00:00 | 2021-12-05T06:15:50.570194+00:00 | 260 | false | ```\nimport java.util.function.Function;\nimport java.util.function.IntConsumer;\n\nclass FizzBuzz {\n private int n;\n private int i;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.i = 1;\n }\n\n private synchronized boolean testAndIncrease(Function<Integer, Boolean> fn) {\n if (i <= n && fn.apply(i))\n i++;\n return i <= n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while (\n testAndIncrease((index) -> {\n if (index % 3 == 0 && index % 5 != 0) {\n printFizz.run();\n return true;\n }\n return false;\n })\n ) ;\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while (\n testAndIncrease((index) -> {\n if (index % 3 != 0 && index % 5 == 0) {\n printBuzz.run();\n return true;\n }\n return false;\n })\n ) ;\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (\n testAndIncrease((index) -> {\n if (index % 3 == 0 && index % 5 == 0) {\n printFizzBuzz.run();\n return true;\n }\n return false;\n })\n ) ;\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while (\n testAndIncrease((index) -> {\n if (index % 3 != 0 && index % 5 != 0) {\n printNumber.accept(index);\n return true;\n }\n return false;\n })\n ) ;\n }\n}\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | JAVA EASY SOLUTION | java-easy-solution-by-aniket7419-r40n | \nclass FizzBuzz {\n private int i;\n private int n=1;\n public FizzBuzz(int n) {\n i = n;\n }\n\n // printFizz.run() outputs "fizz".\n | aniket7419 | NORMAL | 2021-11-29T13:38:50.290912+00:00 | 2021-11-29T13:38:50.290950+00:00 | 251 | false | ```\nclass FizzBuzz {\n private int i;\n private int n=1;\n public FizzBuzz(int n) {\n i = n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while(n<=i)\n {\n synchronized(FizzBuzz.class){\n if(n<=i)\n if(n%3==0&&n%5!=0)\n {\n printFizz.run();\n n++;\n }\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while(n<=i){\n synchronized(FizzBuzz.class){\n if(n<=i)\n if(n%3!=0&&n%5==0)\n {\n printBuzz.run();\n n++;\n }\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while(n<=i){\n synchronized(FizzBuzz.class){\n if(n<=i)\n if(n%5==0&&n%3==0){\n printFizzBuzz.run();\n n++;\n }\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while(n<=i){ \n synchronized(FizzBuzz.class){\n if(n<=i)\n if(n%5!=0&&n%3!=0){\n printNumber.accept(n);\n n++;\n }\n }\n }\n }\n}\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Python3 solution using Barrier | python3-solution-using-barrier-by-barema-5ee7 | Most of the solutions on here are more complicated than they need to be. If you use Barrier to make sure that each thread is looping\nthrough n elements in a sy | baremaximum | NORMAL | 2021-11-06T07:39:23.814157+00:00 | 2021-11-06T07:39:23.814198+00:00 | 149 | false | Most of the solutions on here are more complicated than they need to be. If you use Barrier to make sure that each thread is looping\nthrough `n` elements in a synchronized way, the solution isn\'t much different than regular fizzbuzz.\n```\nfrom threading import Barrier\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.b = Barrier(4)\n self.n = n\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n \n for cnt in range(1, self.n + 1):\n \n if cnt % 3 == 0 and cnt % 5 != 0:\n printFizz()\n \n self.b.wait()\n \n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n \n for cnt in range(1, self.n + 1):\n\n if cnt % 3 != 0 and cnt % 5 == 0:\n printBuzz()\n\n self.b.wait()\n \t\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n \n for cnt in range(1, self.n + 1):\n \n if cnt % 3 == 0 and cnt % 5 == 0:\n printFizzBuzz()\n \n self.b.wait()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n \n for cnt in range(1, self.n + 1):\n \n if cnt % 3 != 0 and cnt % 5 != 0:\n printNumber(cnt)\n \n self.b.wait()\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Very Simple Java ReentrantLock solution | very-simple-java-reentrantlock-solution-nqiaf | All the methods do the same thing, this can be abstracted out. Acquire the lock, do your business, unlock for others and continue. \n\n\n\nclass FizzBuzz {\n | hughesj919 | NORMAL | 2021-09-08T03:17:41.550351+00:00 | 2021-09-08T03:17:41.550391+00:00 | 291 | false | All the methods do the same thing, this can be abstracted out. Acquire the lock, do your business, unlock for others and continue. \n\n```\n\nclass FizzBuzz {\n private int n;\n private int i;\n private ReentrantLock lock;\n\n public FizzBuzz(int n) {\n this.n = n;\n this.i = 1;\n this.lock = new ReentrantLock();\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n Predicate<Integer> pred = val -> val % 5 != 0 && val % 3 == 0;\n runThread(() -> printFizz.run(), pred);\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n Predicate<Integer> pred = val -> val % 5 == 0 && val % 3 != 0;\n runThread(() -> printBuzz.run(), pred);\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n Predicate<Integer> pred = val -> val % 3 == 0 && val % 5 == 0;\n runThread(() -> printFizzBuzz.run(), pred);\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n Predicate<Integer> pred = val -> val % 3 != 0 && val % 5 != 0;\n runThread(() -> printNumber.accept(i), pred);\n }\n \n \n private void runThread(Runnable runnable, Predicate p) throws InterruptedException {\n try {\n lock.lock();\n while (i <= n) {\n if (p.test(i)) {\n runnable.run();\n i++;\n }\n lock.unlock();\n lock.lock();\n }\n \n } finally {\n lock.unlock();\n }\n }\n}\n\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Java | Clean code with synchronized helper function | java-clean-code-with-synchronized-helper-ssu8 | \nclass FizzBuzz {\n private final int n;\n private int i = 1;\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n \n private synchronized | arruw | NORMAL | 2021-07-12T14:50:45.250978+00:00 | 2021-07-12T14:50:45.251025+00:00 | 231 | false | ```\nclass FizzBuzz {\n private final int n;\n private int i = 1;\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n \n private synchronized void helper(Runnable printer, boolean divBy3, boolean divBy5) throws InterruptedException {\n while (i <= n) {\n if ((i % 3 == 0) == divBy3 && (i % 5 == 0) == divBy5) {\n printer.run();\n i++;\n notifyAll();\n } else {\n wait();\n }\n }\n }\n \n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n helper(printFizz, true, false);\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n helper(printBuzz, false, true);\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n helper(printFizzBuzz, true, true);\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n final Runnable printer = new Runnable() {\n @Override\n public void run() {\n printNumber.accept(i);\n }\n };\n helper(printer, false, false);\n }\n}\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | C++ Semaphores / Efficient, Clean, and Easy to Understand | c-semaphores-efficient-clean-and-easy-to-oon4 | \n#include <semaphore.h>\n\nclass FizzBuzz {\nprivate:\n int n;\n \n int count = 1;\n \n sem_t sem_fizz;\n sem_t sem_buzz;\n sem_t sem_fizz | unpoopenzoid | NORMAL | 2021-07-07T22:31:23.132909+00:00 | 2021-07-07T22:33:43.671968+00:00 | 223 | false | ```\n#include <semaphore.h>\n\nclass FizzBuzz {\nprivate:\n int n;\n \n int count = 1;\n \n sem_t sem_fizz;\n sem_t sem_buzz;\n sem_t sem_fizzbuzz;\n sem_t sem_number;\n \n void notify_next() {\n count++;\n \n if (count > n) {\n sem_post(&sem_fizz);\n sem_post(&sem_buzz);\n sem_post(&sem_fizzbuzz);\n sem_post(&sem_number);\n return; \n }\n\n if (count % 15 == 0) {\n sem_post(&sem_fizzbuzz);\n } else if (count % 3 == 0) {\n sem_post(&sem_fizz);\n } else if (count % 5 == 0) {\n sem_post(&sem_buzz);\n } else {\n sem_post(&sem_number);\n }\n }\npublic:\n FizzBuzz(int n) {\n this->n = n;\n sem_init(&sem_fizz, 0, 0);\n sem_init(&sem_buzz, 0, 0);\n sem_init(&sem_fizzbuzz, 0, 0);\n sem_init(&sem_number, 0, 1);\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n while (1) {\n sem_wait(&sem_fizz);\n if (count > n) {\n return;\n }\n printFizz();\n notify_next();\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n while (1) {\n sem_wait(&sem_buzz);\n if (count > n) {\n return;\n }\n printBuzz();\n notify_next();\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n while (1) {\n sem_wait(&sem_fizzbuzz);\n if (count > n) {\n return;\n }\n printFizzBuzz();\n notify_next();\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n while (1) {\n sem_wait(&sem_number);\n if (count > n) {\n return;\n }\n printNumber(count);\n notify_next();\n }\n }\n};\n```\n\nThis code uses a semaphore per thread / function, doesn\'t have the clunky for loop logic of a lot of solutions on here, and efficitiently notifies only threads that need to wake up. The `number()` thread is always the first to print, so that semaphore is initialized to `1`.\n\nOne note about the variable `count`, which is accessed without locks by multiple threads. The code is structured so that only one thread will ever be modifying `count` at a time (in the `notify_next()` function) and during that time no other thread will be reading it. When `count > n` and we need to finish executing, multiple threads will be reading from `count`, but this isn\'t a problem.\n\nPlease let me know if you have any questions or suggestions. Thanks! | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Java, no locks and non-blocking solution | java-no-locks-and-non-blocking-solution-ce6wl | Optimistic locking/ Conditional writes based solution. \n\n\nclass FizzBuzz {\n private int n;\n private int max;\n\n public FizzBuzz(int n) {\n | azhartas | NORMAL | 2021-05-25T10:36:33.485788+00:00 | 2021-05-25T10:42:45.864862+00:00 | 471 | false | Optimistic locking/ Conditional writes based solution. \n\n```\nclass FizzBuzz {\n private int n;\n private int max;\n\n public FizzBuzz(int n) {\n this.max = n;\n this.n = 1;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while(true) {\n int tmp = this.n;\n if(tmp > this.max)\n break;\n if(tmp % 3 == 0 && tmp % 5 != 0) {\n printFizz.run();\n n++;\n }}\n\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while(true) {\n int tmp = this.n;\n if(tmp > this.max)\n break;\n if(tmp % 3 != 0 && tmp % 5 == 0 ) {\n printBuzz.run();\n n++;\n }}\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while(true) {\n int tmp = this.n;\n if(tmp > this.max)\n break;\n if(tmp % 3 == 0 && tmp % 5 == 0) {\n printFizzBuzz.run();\n n++;\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while(true) {\n int tmp = this.n;\n if(tmp > this.max)\n break;\n if(tmp % 3 != 0 && tmp % 5 != 0) {\n printNumber.accept(tmp);\n n++;\n }\n }\n }\n}\n``` | 2 | 1 | ['Java'] | 1 |
fizz-buzz-multithreaded | [Python3] using Lock() | python3-using-lock-by-ye15-bdq8 | \n\nfrom threading import Lock\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.fizzLock = Lock(); self.fizzLock.acquire()\ | ye15 | NORMAL | 2021-05-14T20:19:43.021181+00:00 | 2021-05-14T20:19:43.021208+00:00 | 688 | false | \n```\nfrom threading import Lock\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.fizzLock = Lock(); self.fizzLock.acquire()\n self.buzzLock = Lock(); self.buzzLock.acquire()\n self.fzbzLock = Lock(); self.fzbzLock.acquire()\n self.numberLock = Lock()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n \twhile True: \n self.fizzLock.acquire()\n if self.n == 0: break \n printFizz()\n self.numberLock.release()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n \twhile True: \n self.buzzLock.acquire()\n if self.n == 0: break \n printBuzz()\n self.numberLock.release()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n while True: \n self.fzbzLock.acquire()\n if self.n == 0: break \n printFizzBuzz()\n self.numberLock.release()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for x in range(1, self.n+1):\n self.numberLock.acquire()\n if x % 15 == 0: \n self.fzbzLock.release()\n elif x % 3 == 0: \n self.fizzLock.release()\n elif x % 5 == 0: \n self.buzzLock.release()\n else: \n printNumber(x)\n self.numberLock.release()\n \n self.numberLock.acquire()\n self.n = 0 \n self.fizzLock.release()\n self.buzzLock.release()\n self.fzbzLock.release()\n \n``` | 2 | 0 | ['Python3'] | 0 |
fizz-buzz-multithreaded | C++ MUTEX AND CONDITIONAL VARIABLE 40MS | c-mutex-and-conditional-variable-40ms-by-jcr9 | \nclass FizzBuzz {\nprivate:\n int n;\n mutex m;\n condition_variable fizzCond;\n condition_variable buzzCond;\n condition_variable fizzbuzzCond; | abhi_tom | NORMAL | 2021-04-11T05:04:27.927081+00:00 | 2021-04-11T05:04:27.927110+00:00 | 288 | false | ```\nclass FizzBuzz {\nprivate:\n int n;\n mutex m;\n condition_variable fizzCond;\n condition_variable buzzCond;\n condition_variable fizzbuzzCond;\n condition_variable numberCond;\n int cnt;\n \n bool onlyDivByThree(int n){\n if(n%3==0 and n%5!=0)\n return true;\n return false;\n }\n bool onlyDivByFive(int n){\n if(n%3!=0 and n%5==0)\n return true;\n return false;\n }\n bool DivByBoth(int n){\n if(n%3==0 and n%5==0)\n return true;\n return false;\n }\n bool DivByNone(int n){\n if(n%3!=0 and n%5!=0)\n return true;\n return false;\n }\npublic:\n FizzBuzz(int n) {\n this->n = n;\n cnt=1;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n unique_lock<mutex> locker(m);\n \n while(cnt<=n){\n fizzCond.wait_for(locker,50ms,[&](){\n return onlyDivByThree(cnt);\n });\n \n if(cnt>n){\n cnt++;\n return;\n }\n \n printFizz();\n cnt++;\n \n if(onlyDivByFive(cnt)){\n buzzCond.notify_one();\n } else if(DivByBoth(cnt)){\n fizzbuzzCond.notify_one();\n }else{\n numberCond.notify_one();\n }\n }\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n unique_lock<mutex> locker(m);\n \n while(cnt<=n){\n buzzCond.wait_for(locker,50ms,[&](){\n return onlyDivByFive(cnt);\n });\n \n if(cnt>n){\n cnt++;\n return;\n }\n \n printBuzz();\n cnt++;\n \n if(onlyDivByThree(cnt)){\n fizzCond.notify_one();\n } else if(DivByBoth(cnt)){\n fizzbuzzCond.notify_one();\n }else{\n numberCond.notify_one();\n }\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n unique_lock<mutex> locker(m);\n \n while(cnt<=n){\n fizzbuzzCond.wait_for(locker,50ms,[&](){\n return DivByBoth(cnt);\n });\n \n if(cnt>n){\n cnt++;\n return;\n }\n \n printFizzBuzz();\n cnt++;\n \n if(onlyDivByThree(cnt)){\n fizzCond.notify_one();\n } else if(onlyDivByFive(cnt)){\n buzzCond.notify_one();\n }else{\n numberCond.notify_one();\n }\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n unique_lock<mutex> locker(m);\n \n while(cnt<=n){\n numberCond.wait_for(locker,50ms,[&](){\n return DivByNone(cnt);\n });\n \n if(cnt>n){\n cnt++;\n return;\n }\n \n printNumber(cnt);\n cnt++;\n \n if(onlyDivByThree(cnt)){\n fizzCond.notify_one();\n } else if(onlyDivByFive(cnt)){\n buzzCond.notify_one();\n }else if(DivByBoth(cnt)){\n fizzbuzzCond.notify_one();\n }else{\n numberCond.notify_one();\n }\n }\n }\n};\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | [Java] 7ms | 99% using semaphores for each type of 'token writer' | java-7ms-99-using-semaphores-for-each-ty-a6qq | \nclass FizzBuzz {\n private final int n;\n private final Semaphore numberSemaphore = new Semaphore(1);\n private final Semaphore fizzSemaphore = new S | TheRuminator | NORMAL | 2021-03-10T14:31:26.933628+00:00 | 2021-03-10T14:55:09.051900+00:00 | 480 | false | ```\nclass FizzBuzz {\n private final int n;\n private final Semaphore numberSemaphore = new Semaphore(1);\n private final Semaphore fizzSemaphore = new Semaphore(0);\n private final Semaphore buzzSemaphore = new Semaphore(0);\n private final Semaphore fizzbuzzSemaphore = new Semaphore(0);\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n if (i % 3 == 0 && i % 5 != 0) {\n fizzSemaphore.acquire();\n printFizz.run();\n releaseNextSemaphore(i + 1);\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n if (i % 5 == 0 && i % 3 != 0) {\n buzzSemaphore.acquire();\n printBuzz.run();\n releaseNextSemaphore(i + 1);\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n if (i % 15 == 0) {\n fizzbuzzSemaphore.acquire();\n printFizzBuzz.run();\n releaseNextSemaphore(i + 1);\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n for (int i = 1; i <= n; i++) {\n if (i % 5 != 0 && i % 3 != 0) {\n numberSemaphore.acquire();\n printNumber.accept(i);\n releaseNextSemaphore(i + 1);\n }\n }\n }\n\n public void releaseNextSemaphore(int next) {\n if (next % 15 == 0) {\n fizzbuzzSemaphore.release();\n } else if (next % 3 == 0) {\n fizzSemaphore.release();\n } else if (next % 5 == 0) {\n buzzSemaphore.release();\n } else {\n numberSemaphore.release();\n }\n }\n}\n``` | 2 | 0 | [] | 1 |
fizz-buzz-multithreaded | [Java] Just volatile | java-just-volatile-by-jokersun-7r3j | \nclass FizzBuzz {\n\n private volatile int i;\n\n private final int n;\n\n public FizzBuzz(int n) {\n this.i = 1;\n this.n = n;\n }\n | jokersun | NORMAL | 2021-02-15T12:49:51.560026+00:00 | 2021-03-01T02:13:35.698360+00:00 | 407 | false | ```\nclass FizzBuzz {\n\n private volatile int i;\n\n private final int n;\n\n public FizzBuzz(int n) {\n this.i = 1;\n this.n = n;\n }\n\n public void fizz(Runnable printFizz) throws InterruptedException {\n for (int j = i; j <= n; j = i) {\n if (j % 3 == 0 && j % 5 != 0) {\n printFizz.run();\n i = j + 1;\n }\n Thread.yield();\n }\n }\n\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for (int j = i; j <= n; j = i) {\n if (j % 5 == 0 && j % 3 != 0) {\n printBuzz.run();\n i = j + 1;\n }\n Thread.yield();\n }\n }\n\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for (int j = i; j <= n; j = i) {\n if (j % 3 == 0 && j % 5 == 0) {\n printFizzBuzz.run();\n i = j + 1;\n }\n Thread.yield();\n }\n }\n\n public void number(IntConsumer printNumber) throws InterruptedException {\n for (int j = i; j <= n; j = i) {\n if (j % 3 != 0 && j % 5 != 0) {\n printNumber.accept(i);\n i = j + 1;\n }\n Thread.yield();\n }\n }\n}\n``` | 2 | 0 | [] | 1 |
fizz-buzz-multithreaded | [Python] Barrier solution with explanation | python-barrier-solution-with-explanation-499p | There are four threads, and they need to interate through 1 to n synchronously, meaning that no thread can advance to 2 until all threads have "processed" 1, an | goldie213 | NORMAL | 2021-02-11T02:48:29.881314+00:00 | 2021-02-11T02:48:29.881459+00:00 | 368 | false | There are four threads, and they need to interate through 1 to n synchronously, meaning that no thread can advance to 2 until all threads have "processed" 1, and so on. Therefore we can use Barrier from python, a convenient helper to make every thread wait until all of them reach some condition.\n\n\n```\nimport threading\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.b = threading.Barrier(4)\n \n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for i in range(1, self.n+1):\n if i % 3 == 0 and i % 5 != 0:\n printFizz()\n self.b.wait()\n \n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n \tfor i in range(1, self.n+1):\n if i % 3 != 0 and i % 5 == 0:\n printBuzz()\n self.b.wait()\n\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for i in range(1, self.n+1):\n if i % 3 == 0 and i % 5 == 0:\n printFizzBuzz()\n self.b.wait()\n \n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for i in range(1, self.n+1):\n if i % 3 != 0 and i % 5 != 0:\n printNumber(i)\n self.b.wait()\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | C Solution: mutex and cond wait and broadcast | c-solution-mutex-and-cond-wait-and-broad-swdr | ``\n#include <pthread.h>\ntypedef struct {\n int nsize;\n int cur;\n pthread_mutex_t lock;\n pthread_cond_t cond;\n} FizzBuzz;\n\nFizzBuzz* fizzBuzz | leet_jx | NORMAL | 2020-12-31T17:44:21.527989+00:00 | 2020-12-31T17:44:21.528037+00:00 | 321 | false | ```\n#include <pthread.h>\ntypedef struct {\n int nsize;\n int cur;\n pthread_mutex_t lock;\n pthread_cond_t cond;\n} FizzBuzz;\n\nFizzBuzz* fizzBuzzCreate(int n) {\n FizzBuzz* obj=malloc(sizeof(FizzBuzz));\n obj->nsize=n;\n obj->cur=1;\n pthread_mutex_init(&obj->lock, NULL);\n pthread_cond_init(&obj->cond, NULL);\n return obj;\n}\n\n// printFizz() outputs "fizz".\nvoid fizz(FizzBuzz* obj) {\n while(1){\n pthread_mutex_lock(&obj->lock);\n if(obj->cur > obj->nsize){ \n pthread_mutex_unlock(&obj->lock);\n return;\n }\n if(obj->cur%3==0 && obj->cur%5!=0){\n printFizz();\n obj->cur++;\n pthread_cond_broadcast(&obj->cond);\n }else{\n pthread_cond_wait(&obj->cond, &obj->lock);\n }\n pthread_mutex_unlock(&obj->lock); \n }\n}\n\n// printBuzz() outputs "buzz".\nvoid buzz(FizzBuzz* obj) {\n while(1){\n pthread_mutex_lock(&obj->lock);\n if(obj->cur > obj->nsize){ \n pthread_mutex_unlock(&obj->lock);\n return;\n } \n if(obj->cur%3!=0 && obj->cur%5==0){\n printBuzz();\n obj->cur++;\n pthread_cond_broadcast(&obj->cond);\n }else{\n pthread_cond_wait(&obj->cond, &obj->lock);\n }\n pthread_mutex_unlock(&obj->lock); \n }\n}\n\n// printFizzBuzz() outputs "fizzbuzz".\nvoid fizzbuzz(FizzBuzz* obj) {\n while(1){\n pthread_mutex_lock(&obj->lock); \n if(obj->cur > obj->nsize){\n pthread_mutex_unlock(&obj->lock);\n return;\n }\n if(obj->cur%3==0 && obj->cur%5==0){\n printFizzBuzz();\n obj->cur++;\n pthread_cond_broadcast(&obj->cond);\n }else{\n pthread_cond_wait(&obj->cond, &obj->lock);\n }\n pthread_mutex_unlock(&obj->lock); \n }\n}\n\n// You may call global function `void printNumber(int x)`\n// to output "x", where x is an integer.\nvoid number(FizzBuzz* obj) {\n while(1){\n pthread_mutex_lock(&obj->lock);\n if(obj->cur > obj->nsize){ \n pthread_mutex_unlock(&obj->lock);\n return;\n } \n if(obj->cur%3!=0 && obj->cur%5!=0){\n printNumber(obj->cur);\n obj->cur++;\n pthread_cond_broadcast(&obj->cond);\n }else{\n pthread_cond_wait(&obj->cond, &obj->lock);\n }\n pthread_mutex_unlock(&obj->lock); \n } \n}\n\nvoid fizzBuzzFree(FizzBuzz* obj) {\n pthread_mutex_destroy(&obj->lock);\n pthread_cond_destroy(&obj->cond);\n free(obj);\n}\n | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Java - Beats 100% simple solution | java-beats-100-simple-solution-by-maorbr-gwb1 | java\n\nclass FizzBuzz {\n\tprivate int n;\n\n\tprivate AtomicInteger counter;\n\n\tpublic FizzBuzz(int n) {\n\t\tthis.n = n;\n\t\tthis.counter = new AtomicInte | maorbril | NORMAL | 2020-09-17T23:35:05.844707+00:00 | 2020-09-17T23:35:05.844746+00:00 | 378 | false | ```java\n\nclass FizzBuzz {\n\tprivate int n;\n\n\tprivate AtomicInteger counter;\n\n\tpublic FizzBuzz(int n) {\n\t\tthis.n = n;\n\t\tthis.counter = new AtomicInteger(1);\n\t}\n\n\n // printFizz.run() outputs "fizz".\n\tpublic void fizz(Runnable printFizz) throws InterruptedException {\n\t\twhile (counter.get() <= n) {\n\t\t\tsynchronized(counter) {\n\t\t\t\tif (counter.get() > n) return;\n\t\t\t\tif (counter.get() % 3 == 0 && counter.get() % 5 != 0) {\n\t\t\t\t\tprintFizz.run();\n\t\t\t\t\tcounter.incrementAndGet();\n\t\t\t\t}\n\t\t\t}\n\t\t}\n\t}\n\n // printBuzz.run() outputs "buzz".\n\tpublic void buzz(Runnable printBuzz) throws InterruptedException {\n\t\twhile (counter.get() <= n) {\n\t\t\tsynchronized(counter) {\n\t\t\t\tif (counter.get() > n) return;\n\t\t\t\tif (counter.get() % 5 == 0 && counter.get() % 3 != 0) {\n\t\t\t\t\tprintBuzz.run();\n\t\t\t\t\tcounter.incrementAndGet();\n\t\t\t\t}\n\t\t\t}\n\t\t}\n\t}\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n\tpublic void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n\t\twhile (counter.get() <= n) {\n\t\t\tsynchronized(counter) {\n\t\t\t\tif (counter.get() > n) return;\n\t\t\t\tif (counter.get() % 5 == 0 && counter.get() % 3 == 0) {\n\t\t\t\t\tprintFizzBuzz.run();\n\t\t\t\t\tcounter.incrementAndGet();\n\t\t\t\t}\n\t\t\t} \n\t\t}\n\t}\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n\tpublic void number(IntConsumer printNumber) throws InterruptedException {\n\t\twhile (counter.get() <= n) {\n\t\t\tsynchronized(counter) {\n\t\t\t\tif (counter.get() > n) return;\n\t\t\t\tif (counter.get() % 5 != 0 && counter.get() % 3 != 0) {\n\t\t\t\t\tprintNumber.accept(counter.getAndIncrement());\n\t\t\t\t}\n\t\t\t}\n\t\t}\n\t}\n}\n``` | 2 | 1 | [] | 2 |
fizz-buzz-multithreaded | [C++] Mutex-based Solution Explained, ~70% Time, ~65% Space | c-mutex-based-solution-explained-70-time-wryi | So, we have 4 class variables: n to store our the input passed in the constructor, i to keep track of our currently printed number (initially set to 1), a mutex | ajna | NORMAL | 2020-08-26T20:20:12.936887+00:00 | 2020-08-26T20:20:12.936947+00:00 | 856 | false | So, we have 4 class variables: `n` to store our the input passed in the constructor, `i` to keep track of our currently printed number (initially set to `1`), a [mutex](https://en.cppreference.com/w/cpp/thread/mutex) `m` and a [`condition _variable`](https://en.cppreference.com/w/cpp/thread/condition_variable) `c`.\n\nWe can create a helper `run` in order to avoid too much WET code and we expect it to receive a `check` and a `print` function; inside we will run an infinite loop that constantly locks, wait for a condition in `check` to be valid and move on; if the condition is the first, we are done counting and then we `break`.\n\nOtherwise we run the function, increase `i`, unlock, notify all and move again until done.\n\nProbably not the best solution at all, but I am kind of a n00b on both C++ and multithreading, so feel free to bash me hard on this one with suggestions, criticism and general advice if you wish :)\n\nThe code:\n\n```cpp\nclass FizzBuzz {\nprivate:\n int n, i = 1;\n mutex m;\n condition_variable c;\n\npublic:\n FizzBuzz(int n) {\n // nothing to see here\n this->n = n;\n }\n \n // helper to keep the code a bit DRY\n void run(function<bool(int)> check, function<void(int)> print) {\n while (true) {\n // setting the lock\n unique_lock<mutex> lock(m);\n // setting the conditions\n c.wait(lock, [&](){return i > n || check(i);});\n // breaking if we are done\n if (i > n) break;\n // printing otherwise while also incrementing\n print(i++);\n lock.unlock();\n c.notify_all();\n }\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n run(\n [](int i){return i % 3 == 0 && i % 5;},\n [&](int i){printFizz();}\n );\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n run(\n [](int i){return i % 3 && i % 5 == 0;},\n [&](int i){printBuzz();}\n );\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n run(\n [](int i){return i % 15 == 0;},\n [&](int i){printFizzBuzz();}\n );\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n run(\n [](int i){return i % 3 && i % 5;},\n [&](int i){printNumber(i);}\n );\n }\n};\n``` | 2 | 0 | ['C', 'C++'] | 1 |
fizz-buzz-multithreaded | c# semaphore | c-semaphore-by-code-world-7lcb | Key points of problem:\n\n1. Four threads has same object but calls different method.\n2. This require four threads to signal each other for execution. Think it | code-world | NORMAL | 2020-08-10T06:11:27.911329+00:00 | 2020-08-10T06:11:27.911379+00:00 | 662 | false | Key points of problem:\n\n1. Four threads has same object but calls different method.\n2. This require four threads to signal each other for execution. Think it as a traffic signal, traffic from four side has to wait for there signal to go. This makes Semaphore as my pick for this problem.\n\n\n```\nusing System.Threading;\n\npublic class FizzBuzz {\n private int n;\n private int x;\n private Semaphore semNum;\n private Semaphore semFizz;\n private Semaphore semBuzz;\n private Semaphore semFizzBuzz;\n \n public FizzBuzz(int n) {\n this.n = n;\n this.x = 1;\n semNum = new Semaphore(1,1);\n semFizz = new Semaphore(0,1);\n semBuzz = new Semaphore(0,1);\n semFizzBuzz = new Semaphore(0,1);\n }\n\n // printFizz() outputs "fizz".\n public void Fizz(Action printFizz) {\n while(x <= n){\n semFizz.WaitOne();\n\n if(x > n)\n return;\n \n if(x%3 == 0){\n printFizz();\n x++;\n }\n ReleaseSemaphore(x);\n }\n }\n\n // printBuzzz() outputs "buzz".\n public void Buzz(Action printBuzz) {\n while(x <= n){\n semBuzz.WaitOne();\n\n if(x > n)\n return;\n \n if(x%5 == 0){\n printBuzz();\n x++;\n }\n ReleaseSemaphore(x);\n }\n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n public void Fizzbuzz(Action printFizzBuzz) {\n while(x <= n){\n semFizzBuzz.WaitOne();\n\n if(x > n)\n return;\n \n if(x%15==0){\n printFizzBuzz();\n x++;\n }\n\n ReleaseSemaphore(x);\n }\n }\n\n // printNumber(x) outputs "x", where x is an integer.\n public void Number(Action<int> printNumber) {\n while(x <= n){\n semNum.WaitOne();\n\n if(x > n)\n return;\n \n if(x%3 != 0 && x%5 != 0){\n printNumber(x);\n x++;\n }\n\n ReleaseSemaphore(x);\n }\n }\n \n private void ReleaseSemaphore(int i){\n if(i > n){\n semNum.Release();\n semFizz.Release();\n semBuzz.Release();\n semFizzBuzz.Release();\n return;\n }\n \n if(i % 15 == 0){\n semFizzBuzz.Release();\n } else if(i % 3 == 0){\n semFizz.Release();\n }else if(i % 5 == 0){\n semBuzz.Release();\n }else{\n semNum.Release();\n }\n }\n}\n``` | 2 | 0 | [] | 2 |
fizz-buzz-multithreaded | Need to notify others when we exit thread task- C++ | need-to-notify-others-when-we-exit-threa-1vnd | In many of the C++ posts, I see that we are missing notifying other threads when count > n. Since the order of the execution is never gaurenteed, I belive we ne | swapnai | NORMAL | 2020-06-23T01:38:00.992052+00:00 | 2020-06-23T01:56:00.755429+00:00 | 175 | false | In many of the C++ posts, I see that we are missing notifying other threads when count > n. Since the order of the execution is never gaurenteed, I belive we need to notify others before exiting a thread. \n\n```\nclass FizzBuzz {\nprivate:\n int n;\n int count;\n condition_variable cv;\n mutex mux;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n count = 1;\n }\n\n void run(function<void()> task, function<bool()> predicate) {\n // 0. run forever\n for (;;) {\n // 1. enable lock scope\n {\n // 2. aquire unique lock\n unique_lock<mutex> lck(mux);\n \n // 3. wait for predicate to be true\n cv.wait(lck, [&]() {return predicate() || count > n;});\n // 4. test task exit condition \n if (count > n) {\n lck.unlock();\n cv.notify_all();\n return;\n }\n // 5. mutate data\n task(); count++;\n } // 6. exit lock scope\n // 7. notify other threads\n cv.notify_all();\n }\n }\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n run(printFizz, [&](){return count % 3 == 0 && count % 5 != 0;});\n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n run(printBuzz, [&](){return count % 3 != 0 && count % 5 == 0;}); \n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n run(printFizzBuzz, [&](){return count % 3 == 0 && count % 5 == 0;}); \n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n run([&]() { printNumber(count);}, [&]() { return count % 3 != 0 && count % 5 != 0;}); \n }\n};\n``` | 2 | 0 | [] | 1 |
fizz-buzz-multithreaded | Java simple semaphore | java-simple-semaphore-by-cuny-66brother-6mwl | \nclass FizzBuzz {\n private int n;\n Semaphore f=new Semaphore(1);\n Semaphore b=new Semaphore(1);\n Semaphore fb=new Semaphore(1);\n Semaphore | CUNY-66brother | NORMAL | 2020-05-21T12:15:38.208883+00:00 | 2020-05-21T12:15:38.208960+00:00 | 286 | false | ```\nclass FizzBuzz {\n private int n;\n Semaphore f=new Semaphore(1);\n Semaphore b=new Semaphore(1);\n Semaphore fb=new Semaphore(1);\n Semaphore num=new Semaphore(1);\n public FizzBuzz(int n) {\n this.n = n;\n try{\n f.acquire();\n b.acquire();\n fb.acquire();\n }catch(Exception e){\n \n }\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for(int i=1;i<=n;i++){\n f.acquire();\n if(i%3==0&&i%5!=0){\n printFizz.run();\n num.release();\n }else{\n f.release();\n }\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for(int i=1;i<=n;i++){\n b.acquire();\n if(i%3!=0&&i%5==0){\n printBuzz.run();\n num.release();\n }else{\n b.release();\n }\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for(int i=1;i<=n;i++){\n fb.acquire();\n if(i%3==0&&i%5==0){\n printFizzBuzz.run();\n num.release();\n }else{\n fb.release();\n }\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n for(int i=1;i<=n;i++){\n num.acquire();\n if(i%3==0&&i%5==0){\n fb.release();\n }else if(i%3==0){\n f.release();\n }else if(i%5==0){\n b.release();\n }else{\n printNumber.accept(i);\n num.release();\n }\n }\n f.release();\n b.release();\n fb.release();\n }\n}\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | C : simply sema | c-simply-sema-by-universalcoder12-578l | \ntypedef struct {\n sem_t sn, s3, s5, s35; // Individual semaphores for threads\n int i, n;\n} FizzBuzz;\n\nFizzBuzz* fizzBuzzCreate(int n) {\n FizzBu | universalcoder12 | NORMAL | 2020-03-25T06:55:43.209468+00:00 | 2020-03-25T07:01:42.304025+00:00 | 631 | false | ```\ntypedef struct {\n sem_t sn, s3, s5, s35; // Individual semaphores for threads\n int i, n;\n} FizzBuzz;\n\nFizzBuzz* fizzBuzzCreate(int n) {\n FizzBuzz* obj = malloc(sizeof (FizzBuzz));\n sem_init(&obj->sn, 0, 0); // All three will wait for number-thread to wake them up\n sem_init(&obj->s3, 0, 0);\n sem_init(&obj->s5, 0, 0);\n \n sem_init(&obj->s35, 0, 0);\n obj->i = 1;\n obj->n = n;\n return obj;\n}\n\nvoid fz(void) { printFizz(); }\nvoid bz(void) { printBuzz(); }\nvoid fbz(void) { printFizzBuzz(); }\ninline void cstub(FizzBuzz *obj, sem_t *t, sem_t *n, void (*f) (void));\ninline void pnum(FizzBuzz *o);\ninline void dl(FizzBuzz *o);\n\nvoid fizz(FizzBuzz* obj) {\n cstub(obj, &obj->s3, &obj->sn, fz);\n}\n\nvoid buzz(FizzBuzz* obj) {\n cstub(obj, &obj->s5, &obj->sn, bz); \n}\n\nvoid fizzbuzz(FizzBuzz* obj) {\n cstub(obj, &obj->s35, &obj->sn, fbz); \n}\n\nvoid number(FizzBuzz* obj) {\n pnum(obj);\n}\n\nvoid fizzBuzzFree(FizzBuzz* obj) {\n dl(obj); \n}\n\n// Process number\ninline void pnum(FizzBuzz *o) {\n while (o->i <= o->n) {\n bool m3 = !(o->i % 3);\n bool m5 = !(o->i % 5); \n if (m3 || m5) {\n m3 && m5 ? sem_post(&o->s35) : // Wake up *only* one of the three\n m5 ? sem_post(&o->s5) :\n sem_post(&o->s3);\n sem_wait(&o->sn); // Get ack\n } else\n printNumber(o->i);\n o->i++; \n }\n sem_post(&o->s35); // Wake all three so that they can exit/return\n sem_post(&o->s5);\n sem_post(&o->s3); \n}\n\n// Common stub for all of the above three\ninline void cstub(FizzBuzz *obj, sem_t *t, sem_t *n, void (*f) (void)) {\n while (1) {\n sem_wait(t);\n if (obj->i > obj->n) {\n sem_post(n);\n return;\n }\n f();\n sem_post(n);\n } \n}\n\n// Relinquish the resources\ninline void dl(FizzBuzz *o) {\n sem_destroy(&o->sn);\n sem_destroy(&o->s3);\n sem_destroy(&o->s5);\n sem_destroy(&o->s35);\n free(o); \n}\n```\n | 2 | 0 | ['C'] | 0 |
fizz-buzz-multithreaded | c++ pre-wait solution with mutex and condition_variable | c-pre-wait-solution-with-mutex-and-condi-slgg | with this solution, each thread will lock the mutex and wait only when it is going to print.\n\nclass FizzBuzz {\nprivate:\n int n;\n int cnt;\n mutex | jay6987 | NORMAL | 2020-03-25T01:21:53.239649+00:00 | 2020-03-25T01:46:08.862884+00:00 | 203 | false | with this solution, each thread will lock the mutex and wait only when it is going to print.\n```\nclass FizzBuzz {\nprivate:\n int n;\n int cnt;\n mutex mtx;\n condition_variable cv;\n\npublic:\n FizzBuzz(int n) {\n this->n = n;\n this->cnt = 1;\n }\n\n // printFizz() outputs "fizz".\n void fizz(function<void()> printFizz) {\n for(int i = 3; i<= n; i+=3)\n {\n if(i%5!=0)\n {\n unique_lock lk(mtx); \n cv.wait(lk,[=](){return cnt==i;});\n ++cnt;\n cv.notify_all();\n printFizz();\n }\n } \n }\n\n // printBuzz() outputs "buzz".\n void buzz(function<void()> printBuzz) {\n for(int i = 5; i<= n; i+=5)\n {\n if(i%3!=0)\n {\n unique_lock lk(mtx); \n cv.wait(lk,[=](){return cnt==i;});\n ++cnt;\n cv.notify_all();\n printBuzz();\n }\n } \n }\n\n // printFizzBuzz() outputs "fizzbuzz".\n\tvoid fizzbuzz(function<void()> printFizzBuzz) {\n for(int i = 15; i<= n; i+=15)\n { \n {\n unique_lock lk(mtx); \n cv.wait(lk,[=](){return cnt==i;});\n ++cnt;\n cv.notify_all();\n printFizzBuzz();\n }\n } \n }\n\n // printNumber(x) outputs "x", where x is an integer.\n void number(function<void(int)> printNumber) {\n for(int i = 1; i<= n; ++i)\n {\n if(i%3!=0 && i%5!=0)\n {\n unique_lock lk(mtx); \n cv.wait(lk,[=](){return cnt==i;});\n ++cnt;\n cv.notify_all();\n printNumber(i);\n }\n } \n }\n};\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Java use wait and notifyAll() | java-use-wait-and-notifyall-by-hobiter-6z88 | \nclass FizzBuzz {\n private int n;\n int curr;\n\n public FizzBuzz(int n) {\n this.n = n;\n curr = 1;\n }\n\n // printFizz.run() o | hobiter | NORMAL | 2020-03-14T06:39:21.453269+00:00 | 2020-03-14T06:39:21.453302+00:00 | 537 | false | ```\nclass FizzBuzz {\n private int n;\n int curr;\n\n public FizzBuzz(int n) {\n this.n = n;\n curr = 1;\n }\n\n // printFizz.run() outputs "fizz".\n public synchronized void fizz(Runnable printFizz) throws InterruptedException {\n while(curr <= n) {\n if (curr % 5 == 0 || curr % 3 != 0) {\n wait();\n continue;\n }\n printFizz.run();\n curr++;\n notifyAll();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public synchronized void buzz(Runnable printBuzz) throws InterruptedException {\n while(curr <= n) {\n if (curr % 5 != 0 || curr % 3 == 0) {\n wait();\n continue;\n }\n printBuzz.run();\n curr++;\n notifyAll();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public synchronized void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (curr <= n) {\n if (curr % 5 != 0 || curr % 3 != 0) {\n wait();\n continue;\n }\n printFizzBuzz.run();\n curr++;\n notifyAll();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public synchronized void number(IntConsumer printNumber) throws InterruptedException {\n while (curr <= n) {\n if (curr % 5 == 0 || curr % 3 == 0) {\n wait();\n continue;\n }\n printNumber.accept(curr);\n curr++;\n notifyAll();\n }\n }\n}\n```\nRef: https://leetcode.com/problems/fizz-buzz-multithreaded/discuss/385395/Java-using-synchronized-with-short-explanation. | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | [Java] Use Semaphore | java-use-semaphore-by-yuhwu-sn4d | \nclass FizzBuzz {\n private int n;\n private int number;\n private Semaphore fizzS;\n private Semaphore buzzS;\n private Semaphore fizzBuzzS;\n | yuhwu | NORMAL | 2020-02-04T07:34:59.993932+00:00 | 2020-02-04T07:34:59.993985+00:00 | 426 | false | ```\nclass FizzBuzz {\n private int n;\n private int number;\n private Semaphore fizzS;\n private Semaphore buzzS;\n private Semaphore fizzBuzzS;\n private Semaphore numberS;\n public FizzBuzz(int n) {\n this.n = n;\n number = 0;\n fizzS = new Semaphore(0);\n buzzS = new Semaphore(0);\n fizzBuzzS = new Semaphore(0);\n numberS = new Semaphore(1);\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n for(int i=1; i<=(n/3-n/15); i++){\n fizzS.acquire();\n printFizz.run();\n numberS.release();\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n for(int i=1; i<=(n/5-n/15); i++){\n buzzS.acquire();\n printBuzz.run();\n numberS.release();\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n for(int i=1; i<=n/15; i++){\n fizzBuzzS.acquire();\n printFizzBuzz.run();\n numberS.release();\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n for(int num=1; num<=n; num++){\n numberS.acquire();\n if(num%15==0){\n fizzBuzzS.release();\n }\n else if(num%3==0){\n fizzS.release();\n }\n else if(num%5==0){\n buzzS.release();\n }\n else{\n printNumber.accept(num);\n numberS.release();\n }\n }\n }\n}\n``` | 2 | 0 | [] | 2 |
fizz-buzz-multithreaded | Python 3 using one Barrier | python-3-using-one-barrier-by-kangtastic-3ezg | Maintain a counter as an instance attribute and synchronize execution of the four threads using threading.Barrier(). Barrier() takes a Callable during initializ | kangtastic | NORMAL | 2019-12-11T05:15:51.730498+00:00 | 2019-12-11T05:49:55.007612+00:00 | 432 | false | Maintain a counter as an instance attribute and synchronize execution of the four threads using `threading.Barrier()`. `Barrier()` takes a `Callable` during initialization that will mutate object state immediately before all the threads are released.\n```\nimport threading\n\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n\n self.k = 0\n self.div_3 = None\n self.div_5 = None\n\n def step():\n self.k += 1\n self.div_3 = not self.k % 3\n self.div_5 = not self.k % 5\n\n self.sync = threading.Barrier(4, action=step)\n\n def _thread(self, printer, div_3=False, div_5=False):\n while self.k < self.n:\n self.sync.wait()\n if self.div_3 == div_3 and self.div_5 == div_5:\n printer()\n\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n self._thread(printFizz, div_3=True)\n\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n self._thread(printBuzz, div_5=True)\n\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n self._thread(printFizzBuzz, div_3=True, div_5=True)\n\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n self._thread(lambda: printNumber(self.k))\n```\nThis is the same idea as https://leetcode.com/problems/fizz-buzz-multithreaded/discuss/441036/Very-simple:-Python-Barrier()-94-100 but using constant space.\n | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Very simple: Python Barrier(), 94% / 100% | very-simple-python-barrier-94-100-by-zob-m2jf | We use a single primitive, threading.Barrier. Barrier(4) forces all four threads to count together: all threads pass the barrier if an only if all four threads | zobeebee | NORMAL | 2019-11-30T20:47:09.642300+00:00 | 2019-11-30T21:11:44.588885+00:00 | 279 | false | We use a single primitive, `threading.Barrier`. `Barrier(4)` forces all four threads to count together: all threads pass the barrier if an only if all four threads have reached it. There is one `Barrier` per integer we need to count. That\'s it.\n\n```\nfrom threading import Barrier\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.barriers = [Barrier(4)] * self.n\n\n def count(self, cond, fxn, arg=False):\n for j in range(self.n):\n self.barriers[j].wait()\n i = j + 1\n if cond(i):\n fxn(i) if arg else fxn()\n \n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n self.count(\n lambda i: i % 3 == 0 and i % 5 != 0,\n printFizz\n )\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n self.count(\n lambda i: i % 3 != 0 and i % 5 == 0,\n printBuzz\n )\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n self.count(\n lambda i: i % 3 == 0 and i % 5 == 0,\n printFizzBuzz\n )\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n self.count(\n lambda i: i % 3 != 0 and i % 5 != 0,\n printNumber,\n True\n )\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Python 99.17% time by cheating | python-9917-time-by-cheating-by-easytea-trub | Experimented with different python threading primitives, but performance were all consistently terrible. My guess is that underhanded solutions like these are s | easytea | NORMAL | 2019-10-13T05:24:51.183498+00:00 | 2019-10-13T05:24:51.183544+00:00 | 434 | false | Experimented with different python `threading` primitives, but performance were all consistently terrible. My guess is that underhanded solutions like these are skewing the runtime stats.\n\nCheating solution: store function references and run normal fizzbuzz once all functions are registered. Lock is still necessary to prevent double printing. \n\n```\nfrom threading import Lock\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.registered = 0\n self.lock = Lock()\n\n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n self.printFizz = printFizz\n self.doFizzBuzz()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n self.printBuzz = printBuzz\n self.doFizzBuzz()\n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n self.printFizzBuzz = printFizzBuzz\n self.doFizzBuzz()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n self.printNumber = printNumber\n self.doFizzBuzz()\n \n def doFizzBuzz(self):\n with self.lock:\n self.registered += 1\n if self.registered < 4:\n return\n \n for i in range(1, self.n+1):\n if i % 15 == 0:\n self.printFizzBuzz()\n elif i % 3 == 0:\n self.printFizz()\n elif i % 5 == 0:\n self.printBuzz()\n else:\n self.printNumber(i)\n``` | 2 | 0 | [] | 1 |
fizz-buzz-multithreaded | Java simple AtomicInteger solution without locks. | java-simple-atomicinteger-solution-witho-vg81 | \nclass FizzBuzz {\n private int n;\n AtomicInteger cur = new AtomicInteger(1);\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // prin | todor91 | NORMAL | 2019-10-07T12:09:13.683717+00:00 | 2019-10-07T12:09:13.683754+00:00 | 401 | false | ```\nclass FizzBuzz {\n private int n;\n AtomicInteger cur = new AtomicInteger(1);\n\n public FizzBuzz(int n) {\n this.n = n;\n }\n\n // printFizz.run() outputs "fizz".\n public void fizz(Runnable printFizz) throws InterruptedException {\n while (true) {\n int x = cur.get();\n if (x > n) return;\n if (x % 3 == 0 && x % 5 != 0) {\n printFizz.run();\n cur.incrementAndGet();\n }\n Thread.sleep(1);\n }\n }\n\n // printBuzz.run() outputs "buzz".\n public void buzz(Runnable printBuzz) throws InterruptedException {\n while (true) {\n int x = cur.get();\n if (x > n) return;\n if (x % 3 != 0 && x % 5 == 0) {\n printBuzz.run();\n cur.incrementAndGet();\n }\n Thread.sleep(1);\n }\n }\n\n // printFizzBuzz.run() outputs "fizzbuzz".\n public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {\n while (true) {\n int x = cur.get();\n if (x > n) return;\n if (x % 3 == 0 && x % 5 == 0) {\n printFizzBuzz.run();\n cur.incrementAndGet();\n }\n Thread.sleep(1);\n }\n }\n\n // printNumber.accept(x) outputs "x", where x is an integer.\n public void number(IntConsumer printNumber) throws InterruptedException {\n while (true) {\n int x = cur.get();\n if (x > n) return;\n if (x % 3 != 0 && x % 5 != 0) {\n printNumber.accept(x);\n cur.incrementAndGet();\n }\n Thread.sleep(1);\n }\n }\n}\n``` | 2 | 1 | [] | 2 |
fizz-buzz-multithreaded | C implementation with pthread | c-implementation-with-pthread-by-kamanel-lk03 | \ntypedef enum Status_s{NUM, THR, FIV, THRFIV} Status;\ntypedef struct {\n int n;\n int cur;\n Status s;\n pthread_mutex_t m;\n pthread_cond_t th | kamanelf | NORMAL | 2019-10-03T22:20:36.095244+00:00 | 2019-10-03T22:20:36.095285+00:00 | 587 | false | ```\ntypedef enum Status_s{NUM, THR, FIV, THRFIV} Status;\ntypedef struct {\n int n;\n int cur;\n Status s;\n pthread_mutex_t m;\n pthread_cond_t th;\n pthread_cond_t fv;\n pthread_cond_t thfv;\n pthread_cond_t num;\n} FizzBuzz;\n\nFizzBuzz* fizzBuzzCreate(int n) {\n FizzBuzz* obj = (FizzBuzz*) malloc(sizeof(FizzBuzz));\n pthread_mutex_init(&obj->m, NULL);\n pthread_cond_init(&obj->th, NULL);\n pthread_cond_init(&obj->fv, NULL);\n pthread_cond_init(&obj->thfv, NULL);\n pthread_cond_init(&obj->num, NULL);\n \n obj->s = NUM;\n obj->cur = 1;\n obj->n = n;\n return obj;\n}\n// printFizz() outputs "fizz".\nvoid fizz(FizzBuzz* obj) {\n int i = 3;\n pthread_mutex_lock(&obj->m);\n while(i <= obj->n){\n while(obj->s != THR)\n pthread_cond_wait(&obj->th, &obj->m);\n printFizz();\n obj->s = NUM;\n pthread_cond_signal(&obj->num);\n i += 3;\n if(i % 5 == 0)\n i += 3;\n }\n pthread_mutex_unlock(&obj->m);\n}\n\n// printBuzz() outputs "buzz".\nvoid buzz(FizzBuzz* obj) {\n int i = 5;\n pthread_mutex_lock(&obj->m);\n while(i <= obj->n){\n while(obj->s != FIV)\n pthread_cond_wait(&obj->fv, &obj->m);\n printBuzz();\n obj->s = NUM;\n pthread_cond_signal(&obj->num);\n i += 5;\n if(i % 3 == 0)\n i += 5; \n }\n pthread_mutex_unlock(&obj->m);\n}\n\n// printFizzBuzz() outputs "fizzbuzz".\nvoid fizzbuzz(FizzBuzz* obj) {\n int i = 15;\n pthread_mutex_lock(&obj->m);\n while(i <= obj->n){\n while(obj->s != THRFIV)\n pthread_cond_wait(&obj->thfv, &obj->m);\n printFizzBuzz();\n obj->s = NUM;\n pthread_cond_signal(&obj->num);\n i += 15;\n }\n pthread_mutex_unlock(&obj->m);\n}\n\n// You may call global function `void printNumber(int x)`\n// to output "x", where x is an integer.\nvoid number(FizzBuzz* obj) {\n int i;\n pthread_mutex_lock(&obj->m);\n while(obj->cur <= obj->n){\n while(obj->s != NUM)\n pthread_cond_wait(&obj->num, &obj->m);\n if (obj->cur % 3 == 0 && obj->cur % 5 != 0) {\n obj->s = THR;\n pthread_cond_signal(&obj->th);\n }\n else if (obj->cur % 5 == 0 && obj->cur % 3 != 0) {\n obj->s = FIV;\n pthread_cond_signal(&obj->fv);\n }\n else if (obj->cur % 3 == 0 && obj->cur % 5 == 0) {\n obj->s = THRFIV;\n pthread_cond_signal(&obj->thfv);\n }\n else {\n printNumber(obj->cur);\n }\n obj->cur++;\n }\n pthread_mutex_unlock(&obj->m); \n}\n\nvoid fizzBuzzFree(FizzBuzz* obj) {\n pthread_mutex_destroy(&obj->m);\n pthread_cond_destroy(&obj->th);\n pthread_cond_destroy(&obj->fv);\n pthread_cond_destroy(&obj->thfv);\n pthread_cond_destroy(&obj->num);\n free(obj);\n}\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Python solution using only threading.Lock (not Condition, Semaphore, or Event) | python-solution-using-only-threadinglock-18js | Uses threading.Lock\n\nNot very fast though. Got:\n\n runtime: 64 ms, faster than 27.89% of Python3 submissions\n memory usage: 16.4 MB, less than 100.00% of Py | butterscotchchip | NORMAL | 2019-10-03T03:54:24.057162+00:00 | 2019-10-03T03:56:21.789062+00:00 | 302 | false | Uses `threading.Lock`\n\nNot very fast though. Got:\n\n* runtime: 64 ms, faster than 27.89% of Python3 submissions\n* memory usage: 16.4 MB, less than 100.00% of Python3 submissions\n\n```python\nfrom threading import Lock\n\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.fizzLock = Lock() # div 3\n self.fizzLock.acquire()\n self.buzzLock = Lock() # div 5\n self.buzzLock.acquire()\n self.fizzBuzzLock = Lock() # div 3 and div 5\n self.fizzBuzzLock.acquire()\n self.numberLock = Lock() # else\n\n def _release(self, num):\n if num % 3 == 0 and num % 5 == 0:\n self.fizzBuzzLock.release()\n elif num % 3 == 0:\n self.fizzLock.release()\n elif num % 5 == 0:\n self.buzzLock.release()\n else:\n self.numberLock.release()\n\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n for i in range(1, self.n + 1):\n if i % 3 == 0 and i % 5 != 0:\n self.fizzLock.acquire()\n printFizz()\n self._release(i + 1)\n\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n for i in range(1, self.n + 1):\n if i % 3 != 0 and i % 5 == 0:\n self.buzzLock.acquire()\n printBuzz()\n self._release(i + 1)\n\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n for i in range(1, self.n + 1):\n if i % 3 == 0 and i % 5 == 0:\n self.fizzBuzzLock.acquire()\n printFizzBuzz()\n self._release(i + 1)\n\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n for i in range(1, self.n + 1):\n if i % 3 != 0 and i % 5 != 0:\n self.numberLock.acquire()\n printNumber(i)\n self._release(i + 1)\n``` | 2 | 0 | [] | 0 |
fizz-buzz-multithreaded | Python naive condition variable | python-naive-condition-variable-by-make_-gigc | ~~~python\n\nfrom threading import Condition\nclass FizzBuzz:\n def init(self, n: int):\n self.n = n\n self.cur = 1\n self.cv = Conditio | make_up | NORMAL | 2019-09-29T19:40:26.353323+00:00 | 2019-09-29T19:40:26.353381+00:00 | 408 | false | ~~~python\n\nfrom threading import Condition\nclass FizzBuzz:\n def __init__(self, n: int):\n self.n = n\n self.cur = 1\n self.cv = Condition()\n\n def next(self):\n self.cur+=1\n self.cv.notify_all()\n \n # printFizz() outputs "fizz"\n def fizz(self, printFizz: \'Callable[[], None]\') -> None:\n while 1:\n with self.cv:\n self.cv.wait_for(lambda : self.cur > self.n or (self.cur % 3 == 0 and self.cur%5 !=0))\n if self.cur > self.n:\n return\n printFizz()\n self.next()\n\n # printBuzz() outputs "buzz"\n def buzz(self, printBuzz: \'Callable[[], None]\') -> None:\n while 1:\n with self.cv:\n self.cv.wait_for(lambda : self.cur > self.n or (self.cur % 5 == 0 and self.cur%3 != 0))\n if self.cur > self.n:\n return\n printBuzz()\n self.next()\n \n\n # printFizzBuzz() outputs "fizzbuzz"\n def fizzbuzz(self, printFizzBuzz: \'Callable[[], None]\') -> None:\n while 1:\n with self.cv:\n self.cv.wait_for(lambda : self.cur > self.n or (self.cur % 3 == 0 and self.cur%5 == 0))\n if self.cur > self.n:\n return\n printFizzBuzz()\n self.next()\n\n # printNumber(x) outputs "x", where x is an integer.\n def number(self, printNumber: \'Callable[[int], None]\') -> None:\n while 1:\n with self.cv:\n self.cv.wait_for(lambda : self.cur > self.n or (self.cur % 3 != 0 and self.cur%5 !=0))\n if self.cur > self.n:\n return\n printNumber(self.cur)\n self.next()\n~~~\nnaive and simple :) | 2 | 0 | [] | 0 |
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