id
stringlengths
36
36
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1.25M
b73cc7cf-3d52-48c7-9606-81cf98cb1cd8
public ListNode mergeKLists(ArrayList<ListNode> lists) { ListNode res = null; for(ListNode a: lists) { res = mergeLists(res, a); } return res; }
cf876dfe-bebb-43fb-8ca1-dca235d0a8ba
public ListNode mergeLists(ListNode A, ListNode B) { if(A == null) return B; if(B == null) return A; ListNode dummy = new ListNode(0); ListNode currA = A, currB = B, curr = dummy; while(currA!=null || currB!=null) { if(currA == null) { curr.next = currB;...
9b26210d-fdca-40cc-8adb-dc034fa81fb9
public ListNode insertionSortList(ListNode head) { ListNode res = null, curr=head; while(curr!=null) { ListNode next =curr.next; curr.next = null; res = InsertNode(curr, res); curr= next; } return res; }
e3b21cc1-3e10-40e2-a38c-99d5020e60dc
private ListNode InsertNode(ListNode node, ListNode list) { if(list==null) return node; ListNode dummy =new ListNode(-1); dummy.next = list; ListNode curr=list, pre = dummy; while(curr != null && curr.val<node.val) { pre = curr; curr= curr.next; } pre.next =...
24aca5cd-0eab-4ba8-b126-6394a3e0954d
public ListNode sortList(ListNode head) { if(head == null || head.next == null) return head; ListNode slow=head, fast = head; while(fast.next!=null && fast.next.next !=null) { fast=fast.next.next; slow = slow.next; } ListNode right = slow.next; slow.next = null...
578515e8-5652-488e-bc20-4a12a092ce95
public static void main (String args[]) { int A[][] = {{1,2,3},{8,1,4}, {7,6,5}}; int B[] = {2,2,3,2}; HashSet<String> dict = new HashSet<String>(); dict.add("hot"); dict.add("cog"); dict.add("dog"); dict.add("tot"); dict.add("hog"); dict.add("hop"); dict.add("pot"); dict.add("dot"); Arr...
30a7d1b1-d19a-4fef-9ece-8b1e98e0843a
Interval() { start = 0; end = 0; }
f3563786-ac07-4438-abce-c4de6a0904b9
Interval(int s, int e) { start = s; end = e; }
3037c2b2-56be-4fe8-9da5-42e8b2983241
public double findMedianSortedArrays(int A[], int B[]) { int a = A.length; int b = B.length; if((a+b)%2 == 0) { double first = find_K(A, 0, B, 0, (a+b)/2); double second = find_K(A, 0, B, 0, (a+b)/2+1); return (first+second)/2.0; }else { ...
534cb283-1b99-4208-aa27-e03fc8763f6e
private int find_K(int A[], int startA, int B[], int startB, int k) { if(A.length ==0 || A.length <= startA) return B[startB+k-1]; if(B.length ==0 || B.length <= startB) return A[startA+k-1]; if(k==1) { if(A[startA]<B[startB]) return A[startA]; else ...
2c6806f0-c4b4-4637-b143-632f5d0dec6e
public int singleNumberBF(int[] A) { ArrayList<Integer> arrlist = new ArrayList<Integer>(); if(A.length == 1) return A[0]; for(int i=1; i<A.length; i++) { if(arrlist.contains(i)) arrlist.remove(i); else arrlist.add(i); } return arrlist.get(0); }
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public int singleNumber(int[] A) { int x=0; if(A.length == 1) return A[0]; for(int i=0; i<A.length; i++) { x=x^A[i]; System.out.println(x); } return x; }
81460a29-e64b-47f0-942f-07efd19f7011
public int longestConsecutive(int[] num) { HashMap<Integer, Boolean> maps= new HashMap<Integer, Boolean>(); int maxLengh = 0; for(int i=0; i<num.length; i++) maps.put(num[i], false); for(int i=0; i<num.length; i++) { if(maps.get(num[i]) ==true) continue...
8a48a781-999d-43b5-b127-71f3ff638955
public int[] twoSum(int[] numbers, int target) { HashMap<Integer, Integer> maps = new HashMap<Integer, Integer>(); for(int i=0; i<numbers.length; i++) { maps.put(numbers[i], i); } for(int i=0; i<numbers.length; i++) { if(maps.containsKey(target-...
06a043e7-3275-457e-8a82-f5b071067dae
public int[] twoSumBF(int[] numbers, int target) { for(int i=0; i<numbers.length; i++) { for(int j=i+1; j<numbers.length; j++) { if (numbers[i] + numbers[j] == target) return new int[]{i, j}; } } return numbers; }
af38943c-7bb3-40a0-bef4-a84a9a27f653
public ArrayList<ArrayList<Integer>> threeSum(int[] num) { ArrayList<ArrayList<Integer>> result = new ArrayList<ArrayList<Integer>>(); if(num.length<3) return result; Arrays.sort(num); int lastUniqe = num[0]; for(int i=0; i<num.length; i++) { if(i==0 || num[i] !...
754efba9-ca89-4381-9eea-cb415a38817e
private ArrayList<ArrayList<Integer>> twoSumInternal(int[] numbers, int target, int startpos) { ArrayList<ArrayList<Integer>> result = new ArrayList<ArrayList<Integer>>(); if(numbers.length<2) return result; HashMap<Integer, Integer> maps = new HashMap<Integer, Integer>(); int lastUniqe = numbers[0]...
0465773e-c39d-490c-a146-44f1af352f46
public int threeSumClosest(int[] num, int target) { int result = 0; int gap = Integer.MAX_VALUE; if(num.length<3) return 0; Arrays.sort(num); for(int i=0; i<num.length-2; i++) { int two = twoSumClosest(num, target-num[i], i+1); if(Math.abs(num[i]+two...
7cf5f166-dae6-4a10-b753-b679cfdb8d29
private int twoSumClosest(int[] numbers, int target, int startpos) { int result = 0; int gap = Integer.MAX_VALUE; int start = startpos; int end = numbers.length -1; while (start<end) { if(Math.abs(numbers[start] + numbers[end] - target) < gap) { gap = Math....
33eb5f03-0fd4-455a-8b5f-ec311fc5c77d
public int removeElement(int[] A, int elem) { int newindex = 0; for(int i=0; i< A.length; i++) { if (A[i] != elem) { A[newindex] = A[i]; newindex++; } } return newindex; }
c2353ef0-10b8-4a4c-b17c-ad917f855ae8
public ArrayList<ArrayList<Integer>> fourSum(int[] num, int target) { ArrayList<ArrayList<Integer>> results = new ArrayList<ArrayList<Integer>>(); Arrays.sort(num); for(int i=0; i<num.length-3; i++) { int a = num[i]; for (int j=i+1; j<num.length-2; j++) ...
d6dde750-dcde-439b-8f38-1c2c8860240e
public ArrayList<ArrayList<Integer>> combinationSum(int[] candidates, int target) { ArrayList<ArrayList<Integer>> results = new ArrayList<ArrayList<Integer>>(); for(int i=0; i<candidates.length; i++) { } HashSet<String> unique = new HashSet<String>(); for(int...
541d7801-3166-4173-8cf3-ee63106a9a0a
public void nextPermutation1(int[] num) { if(num.length<=1) return; if(IsLargest(num, 0)) { Arrays.sort(num); return; } int startpos=0; while(startpos<num.length) { if(!IsLargest(num, startpos+1)) { startpos++; }else { int oldStart = n...
e8c36fa4-2cda-462d-ad15-9a5f968305a8
private boolean IsLargest(int[] num, int startPos) { if (startPos>=num.length-1) return true; for(int i=startPos; i< num.length-1; i++) { if(num[i] >= num[i+1]) continue; else return false; } return true; }
4b6621d1-c941-4131-a140-56683a2f8386
public void nextPermutation(int[] num) { if(num.length<=1) return; int startpos=num.length-1; while(startpos>0) { if(num[startpos] <= num[startpos-1]) { startpos--; }else { for(int i=num.length-1; i>startpos-1; i--) { if(num[i]>num[startp...
85e04a6d-ff0f-40e1-85de-235c7e440991
public String getPermutation(int n, int k) { String result = ""; ArrayList<Integer> num = new ArrayList<Integer>(); //construct the first element for(Integer i=0; i<n; i++) { num.add(i+1); } int skipnumber = factorial(n-1); for(int i=n; i>1; i-...
3fe83106-949e-4020-91dd-c111b76777c3
private int factorial(int n) { int result= 1; for(int i=1; i<=n; i++) { result *=i; } return result; }
8d1b80d1-9d65-48d4-9753-9a73bc1b4508
public ArrayList<ArrayList<Integer>> permute(int[] num) { ArrayList<ArrayList<Integer>> results = new ArrayList<ArrayList<Integer>>(); Arrays.sort(num); return permuteInternal(num, 0); }
0effe987-c0ce-4f8d-8633-f0cea86481cb
private ArrayList<ArrayList<Integer>> permuteInternal(int[] num, int start) { ArrayList<ArrayList<Integer>> results = new ArrayList<ArrayList<Integer>>(); Arrays.sort(num); if(start>=num.length-1) { ArrayList<Integer> res = new ArrayList<Integer>(); res.add(num[start]); ...
6974d7da-622c-4e4a-9e96-efca21561676
public ArrayList<ArrayList<Integer>> permuteUnique(int[] num) { ArrayList<ArrayList<Integer>> results = new ArrayList<ArrayList<Integer>>(); Arrays.sort(num); results = permuteInternalUnique(num, 0); return results; }
d0785ff4-9f55-48b8-b408-535480321c87
private ArrayList<ArrayList<Integer>> permuteInternalUnique(int[] num, int start) { ArrayList<ArrayList<Integer>> results = new ArrayList<ArrayList<Integer>>(); Arrays.sort(num); if(start>=num.length-1) { ArrayList<Integer> res = new ArrayList<Integer>(); res.add(num[star...
7ecd967c-7094-40df-83b7-08bd9b22d1b1
public boolean isValidSudoku(char[][] board) { Boolean[] used = new Boolean[9]; for(int i=0; i<9; i++) { for(int k=0; k<9; k++) used[k]=false; for(int j=0; j<9; j++) { char value = board[i][j]; if(value !='.') { ...
fac77a76-bffc-471a-8edc-8312e225ff04
public int trap(int[] A) { if(A.length<3) return 0; int water = 0; int maxLeft[] = new int[A.length]; maxLeft[0] = 0; int maxRight[] = new int[A.length]; maxRight[A.length-1] = 0; for(int i=1; i<A.length; i++) { if(maxLeft[i-1] < A[i-1]) { maxLeft...
8e42365c-4173-47b0-b9b4-c6a5c6a11fba
public int climbStairsRecursion(int n) { if(n==1) return 1; if (n==2) return 2; return climbStairsRecursion(n-1) + climbStairsRecursion(n-2); }
eecfe633-4e68-4cae-aca8-ac76a9a0282a
public int climbStairs(int n) { if(n==1) return 1; if (n==2) return 2; int[] num= new int[n+1]; num[1] = 1; num[2] = 2; for(int i=3; i<=n; i++) { num[i] = num[i-1] + num[i-2]; } return num[n]; }
7813d12b-c38d-44a6-a694-046f5c4065fc
public int candy(int[] ratings) { int[] candy = new int[ratings.length]; int res = 0; candy[0] = 1; for(int i=1; i<ratings.length;i++) { if(ratings[i]>ratings[i-1]) { candy[i] = candy[i-1] + 1; }else { ...
88eb1cab-8478-4616-a3f5-a02795dbc822
public void rotate(int[][] matrix) { int temp = 0; int midWidh = (matrix.length+1)/2; int midHeigh = matrix.length/2; int n = matrix.length; if(n==1) return; for(int i=0; i<midWidh; i++) { for(int j=0; j<midHeigh; j++) { temp = matrix[j][i]; matrix[j][i...
4357559e-3810-44e8-aa5e-a2b5d2fdbf9c
public int[] plusOne(int[] digits) { for(int i=digits.length-1; i>=0; i--) { if(digits[i] ==9) { digits[i] = 0; }else { digits[i] ++; return digits; } } int[] result = new int[digits.length+1]; ...
b4769592-9df0-4527-98d8-7fc104e707ce
public void setZeroes(int[][] matrix) { boolean[] row = new boolean[matrix.length]; boolean[] col = new boolean[matrix[0].length]; for(int i=0; i<matrix.length; i++) { for(int j=0; j<matrix[i].length; j++) { if(matrix[i][j] ==0) { ro...
fb93dd8e-3a99-4df5-8a25-3be171272651
public boolean searchMatrix1(int[][] matrix, int target) { int start = 0; int end = matrix.length-1; int row=0; while(start<=end) { int midrow = (start + end)/2; if(target<matrix[midrow][0]) { end = midrow-1; }else if(target>=matrix[midrow][0] &...
304aa374-2129-4774-bbe0-9f8bb6f472ac
public boolean searchMatrix(int[][] matrix, int target) { int start = 0; int end = matrix.length *matrix[0].length-1; int row=0; while(start<=end) { int mid = (start + end)/2; int x = mid/matrix[0].length; int y = mid % matrix[0].length; if(target<matr...
6bf634f4-c071-44f0-acd4-9e7fa29af378
public int canCompleteCircuit(int[] gas, int[] cost) { int res = -1; int n = gas.length; int total = 0; int[] gap = new int[n]; for(int i=0, j=0; i<n; i++, j++) { if(i==0) gap[i] = gas[i] - cost[i]; else gap[i] = gap[i-1] + gas[i] - ...
b87f5055-1611-46ab-8db4-072ea04808a7
public int largestRectangleAreaTLE(int[] height) { int [] area = new int[height.length]; int [] area2 = new int[height.length]; for(int i=0; i<height.length; i++) { int left = height[i]; int unit = 1; for(int j=i+1; j<height.length; j++) { if(height[j]>=left) ...
bebce364-8702-4a62-bfa5-e84faf29cf71
public void merge(int A[], int m, int B[], int n) { int i=m-1,j=n-1, k=m+n-1; while(i>=0 && j>=0) { if(A[i] > B[j]) { A[k] = A[i]; i--; }else { A[k] = B[j]; j--; } k--; } while(j...
f20360af-955a-418d-90be-3c785aa76756
public int firstMissingPositive(int[] A) { for(int i =1; i<=A.length; i++) { int j; for(j=0; j<A.length; j++) { if(A[j] == i) break; } if(j==A.length) return i; } return A.length+1; }
71ea72f5-f5c5-4f53-84d4-63debb776f37
public void sortColors(int[] A) { quicksort(A, 0); quicksort(A, 1); }
8ab3e1ec-30e5-469c-844e-e9ba6d25fa17
private void quicksort(int[] A, int mid) { int i=0, j=A.length-1; while(i<j) { if(A[i]<=mid) i++; else if(A[j]>mid) j--; else{ int t = A[i]; A[i] = A[j]; A[j] = t; i++; j--; } } }
76456de7-1b3c-4f15-be52-c8aae77b0130
public int[] searchRange(int[] A, int target) { int l=0, r=A.length-1, mid=A.length/2; boolean bfound = false; while(l<=r) { if(A[mid]<target) { l=mid+1; mid=(l+r)/2; }else if(A[mid]>target) { r=mid-1; mid=(l+r)...
b5dfe431-e9e4-4ff5-9b1d-e2e0a8c9eda0
public int searchInsert(int[] A, int target) { int l=0, r=A.length-1, mid=A.length/2; while(l<=r) { if(A[mid]<target) { l=mid+1; mid=(l+r)/2; }else if(A[mid]>target) { r=mid-1; mid=(l+r)/2; }else { ...
bd29edd5-acd2-4e2e-a2fd-16d4ee3c63c9
public ArrayList<ArrayList<Integer>> subsets(int[] S) { Arrays.sort(S); return subsets(S, 0); }
261ab4e8-0837-4948-89df-96f49c9e748e
private ArrayList<ArrayList<Integer>> subsets(int[] S, int startpos) { ArrayList<ArrayList<Integer>> res = new ArrayList<ArrayList<Integer>>(); if(startpos == S.length-1) { ArrayList<Integer> t = new ArrayList<Integer>(); t.add(S[startpos]); res.add(t); res.add(new Arra...
246f5a32-4030-4dec-8c6f-1d75bccbf942
public static void main (String args[]) { int A[] = {2,1}; int B[] = {1,2}; test testA =new test(); testA.canCompleteCircuit(B, A); System.out.println(); }
dffb59d9-6c9b-434d-93e8-c8dbbd3d0029
public ArrayList<ArrayList<Integer>> subsetsWithDup(int[] num) { Arrays.sort(num); return subsetsWithDup(num, 0); }
a1d58eff-39d5-4c7a-904a-2ba4d40b4376
public boolean isValid(String s) { Stack<Character> a =new Stack<Character>(); for(char x:s.toCharArray()) { if(x=='[' || x=='(' || x=='{' ) { a.push(x); }else { if(a.empty()) return false; char y=(Character)a.pop(); if((x==']' && y=='[') || (x=='}' &&...
3718d186-529e-4b4a-ad59-bb0a53ef5ae7
public int longestValidParentheses(String s) { Stack<Character> a =new Stack<Character>(); int size = 0; int longest = 0; char[] arrays = s.toCharArray(); for(char x:arrays) { if(x=='(') { a.push(x); }else { if(a.empty()) { size = 0; ...
0f878fc1-15b3-490d-b4d3-f6d3f2f54b43
public int evalRPN(String[] tokens) { Stack<Integer> cal = new Stack<Integer>(); for(int i=0; i<tokens.length; i++) { try{ int num = Integer.parseInt(tokens[i]); cal.push(num); } catch (NumberFormatException e) { int op2 = (int) cal.pop(); int op1 = (int) ...
913f1291-9bba-4b65-99c0-2ed3fef5e568
private ArrayList<ArrayList<Integer>> subsetsWithDup(int[] S, int startpos) { ArrayList<ArrayList<Integer>> res = new ArrayList<ArrayList<Integer>>(); if(startpos == S.length-1) { ArrayList<Integer> t = new ArrayList<Integer>(); t.add(S[startpos]); res.add(t); res.add(n...
4062d381-55e5-4f72-b2aa-9de3543a12a4
public ArrayList<ArrayList<Integer>> combine(int n, int k) { ArrayList<ArrayList<Integer>> res = new ArrayList<ArrayList<Integer>>(); if(k==0 || k>n) return res; if(k==1) { for(int i=1; i<=n; i++) { ArrayList<Integer> t = new ArrayList<Integer>(); t.add(i); re...
9821f991-3b8f-41cb-8023-b87cdbe935e5
public double pow(double x, int n) { if(n==0) return 1; if(n==1) return x; if(n==-1) return 1/x; double res = pow(x, n/2); return res * res * pow(x, n-(n/2)*2); }
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public int sqrt(int x) { if(x<=1) return x; int l=1, r=x/2, mid, res=0; while(l<=r) { mid = (l+r)/2; if(x/mid == mid) return mid; else if(x/mid < mid) r=mid-1; else{ l=mid+1; res = mid; } } return res; }
67ba18bd-54ee-444a-8689-a77ca2fa7af2
public boolean canJump(int[] A) { if(A.length<=1) return true; int reach = 1; for(int i=0; i<A.length-1; i++) { reach = Math.max(reach-1, A[i]); if(reach<=0) return false; } return reach >=0; }
3d06189e-bd6c-4146-a162-6c969c664898
public int jump(int[] A) { if(A.length<=1) return 0; int left = 1; int end = A[0]; int step = 1; while(end<A.length) { int max = 0; int i = left; for(i=left; i<=end; i++) { if(i>=A.length-1) return step; max = Math.max(max, i+...
826dcf77-afd2-4313-9248-a31005ce0c4b
public int maxProfit1(int[] prices) { if(prices.length<=1) return 0; int min=prices[0]; int gap = 0; for(int i=1; i<prices.length; i++) { min = Math.min(min, prices[i]); gap = Math.max(gap, prices[i]-min); } return gap; ...
365ddfbd-35c1-4a26-9e0e-ca440beefa06
public int maxProfit2(int[] prices) { if(prices.length<=1) return 0; int min=prices[0]; int gap = 0; for(int i=1; i<prices.length; i++) { if(prices[i]<prices[i-1]) min = Math.min(min, prices[i]); else gap += prices[i]-prices[i-...
2f46d754-8f22-49ea-a168-23d553fecfec
public int maxProfit(int[] prices) { int sum = 0; for(int i=1; i<prices.length-1; i++) { int[] left = Arrays.copyOfRange(prices, 0, i); int[] right = Arrays.copyOfRange(prices, i, prices.length); sum = Math.max(sum, maxProfit1(left)+ maxProfit1(right)); } return sum; }
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public int maxArea(int[] height) { if(height.length<=1) return 0; int left = 0; int right = height.length-1; int max = 0; while(left<right) { int t = Math.min(height[left], height[right]); max = Math.max(max, t*(right-left)); if(height[left] <= height[right]) ...
489ce446-6965-4f44-998c-956cc0d84185
public int ladderLength(String start, String end, HashSet<String> dict) { if (dict.size() == 0) return 0; LinkedList<String> wordQueue = new LinkedList<String>(); LinkedList<Integer> distanceQueue = new LinkedList<Integer>(); wordQueue.add(start); distan...
3351be6c-1789-43c2-9489-5400ce12c16b
public ArrayList<ArrayList<String>> findLaddersETL(String start, String end, HashSet<String> dict) { ArrayList<ArrayList<String>> res = new ArrayList<ArrayList<String>>(); HashMap<String, ArrayList<ArrayList<String>>> path = new HashMap<String, ArrayList<ArrayList<String>>>(); HashSet<String> used = new ...
021555d2-465d-41a6-bbff-bd5c8a0f0c4b
public ArrayList<ArrayList<String>> findLadders(String start, String end, HashSet<String> dict) { HashMap<String, HashSet<String>> visited = new HashMap<String, HashSet<String>>(); HashMap<String, Integer> level = new HashMap<String, Integer>(); LinkedList<String> queue = new LinkedList<String>(...
8e1ce29c-3eee-495e-aedb-d0f2bebaa5f4
private ArrayList<ArrayList<String>> backtrace(String end, HashMap<String, HashSet<String>> visited, ArrayList<String> path) { ArrayList<ArrayList<String>> result = new ArrayList<ArrayList<String>>(); ArrayList<String> entry = new ArrayList<String>(path); entry.add(0,end); if(visited.get(end).size()<1){ re...
0d4ec012-b840-4052-bd05-2ea7190f30d3
public void solve(char[][] board) { if(board.length==0 || board[0].length==0) return; int length = board.length; int width = board[0].length; ArrayList<Integer> Iindexes =new ArrayList<Integer>(); ArrayList<Integer> Jindexes =new ArrayList<Integer>(); for...
bb75099b-d5ef-411c-b3f3-fd41e965cb80
public int minimumTotal(ArrayList<ArrayList<Integer>> triangle) { if(triangle.size() ==0) return 0; int[] minvalues = new int[triangle.size()]; int min = Integer.MAX_VALUE; for(int row =0; row<triangle.size(); row ++) { for(int index = triangle.get(row).size()-1; index >=0; inde...
976b361f-93da-45f0-a35f-5c22dccfadfd
private int getMin(int row, int index, ArrayList<ArrayList<Integer>> triangle, int[] minvalues) { int val = triangle.get(row).get(index); int minvalue = 0; if(row == 0) { minvalue = val; }else { if(index==0) { minvalue = minvalues[index] + val; } ...
fed20eaf-6ac5-4e31-a780-1f855ccb7672
public int maxSubArray(int[] A) { int[] largest = new int[A.length]; largest[0] = A[0]; for(int i=1; i<A.length; i++) { if(largest[i-1]<0) { largest[i] = A[i]; }else { largest[i] = largest[i-1]+A[i]; } } int max = A[0]; ...
769463e9-5ea0-4170-89a5-978a7909a078
public ArrayList<ArrayList<Integer>> generate(int numRows) { ArrayList<ArrayList<Integer>> res = new ArrayList<ArrayList<Integer>>(); for(int i=0; i<numRows; i++) { ArrayList<Integer> row = new ArrayList<Integer>(); row.add(1); if(i>0) { ArrayList<Integer> prevrow = res.get...
41522528-2377-480d-b5d1-20664940184b
public ArrayList<Integer> getRow(int rowIndex) { ArrayList<Integer> res = new ArrayList<Integer>(); for(int i=0; i<rowIndex+1; i++) { res.add(0, 1); for(int j=1; j<res.size()-1; j++) { res.set(j, res.get(j+1)+res.get(j)); } } return res; }
3d83919b-9ece-4033-bf84-b94f63d56d1e
public int minPathSum(int[][] grid) { int[][] sum = new int[grid.length][grid[0].length]; sum[0][0] = grid[0][0]; for(int i=1; i<grid.length; i++) sum[i][0] = grid[i][0] + sum[i-1][0]; for(int j=1; j<grid[0].length; j++) sum[0][j] = grid[0][j] + sum[0][j-1]; for(int i=1;...
fc1d74a8-3daf-4bfe-bf8c-21e8444badaf
public ArrayList<Integer> spiralOrder(int[][] matrix) { ArrayList<Integer> res = new ArrayList<Integer>(); if(matrix.length==0 || matrix[0].length==0) return res; int left = 0, top = 0; int right = matrix[0].length, bottom = matrix.length; while(top<bottom&&left<right) { ...
973dae6e-3f00-41dd-b510-17be9e805714
private void loop(int[][] matrix, ArrayList<Integer> res, int left, int top, int right, int bottom) { for(int j=left; j<right; j++) res.add(matrix[top][j]); for(int i=top+1; i<bottom; i++) res.add(matrix[i][right-1]); for(int j=right-2; j>=left && top<bottom-1; j--) res.ad...
20726559-cd1f-4f22-b33c-b92102c5723f
public int[][] generateMatrix(int n) { int[][] res = new int[n][n]; int size = n; int startNumber = 1; int startpos = 0; while(size>0) { loop(res, startpos, size, startNumber); startNumber= startNumber+(size-1)*4; startpos++; size=size-2; } return res; ...
7930b013-f458-4746-b544-ed392b2e0036
private void loop(int[][] res, int startpos, int size, int startNumber) { if(size==1) { res[startpos][startpos] = startNumber; return; } for(int j=startpos; j<startpos+size-1; j++, startNumber++) res[startpos][j]=startNumber; for(int i=startpos; i<startpos+size-1; i++, start...
c4950fb7-cfca-4336-a84f-eec553848736
public ArrayList<Interval> insert(ArrayList<Interval> intervals, Interval newInterval) { if(intervals.size() == 0) { intervals.add(newInterval); return intervals; } boolean bMerged = false; for(int i=0; i<intervals.size(); i++){ if(!bMerged && intervals.get(i).end<newInterval.sta...
1cbddbf9-c2a3-4de3-a187-a9df1f6f42eb
public ArrayList<Interval> merge(ArrayList<Interval> intervals) { if(intervals.size() <=1) return intervals; ArrayList<Interval> res =new ArrayList<Interval>(); res.add(intervals.get(0)); for(int i=0; i<intervals.size(); i++) { res = insert(res, intervals.get(i)); } retur...
788db22f-6ea1-447a-a505-453fbe2f7836
public int minDistance(String word1, String word2) { if(Math.min(word1.length(), word2.length()) ==0 ) return Math.max(word1.length(), word2.length()); int[][] min1 = new int[word1.length()][word2.length()]; return getMin(word1, word2, min1, 0, 0); }
95ee8ddf-a3ab-4935-b852-1ade4a1b28e8
private int getMin(String word1, String word2, int[][] min1, int index1, int index2) { if(index1==word1.length()) { for(int j=index2; j<word2.length(); j++) min1[index1][j] = word2.substring(index2+1).length(); return word2.substring(index2).length(); }else if(index2==...
9442b38a-fdc9-4760-abe2-c1d548aaba76
public int numDecodings(String s) { if(s.length() == 0) return 0; int[] num = new int[s.length()]; if(s.charAt(0)>'0') num[0]=1; else num[0]=0; for(int i=1; i<s.length(); i++) { int path1 = 0, path2=0; if(s.charAt(i)>'0') path1 = num[i-1]; if((s.cha...
1fe5602b-00a6-49e8-ad3c-99ca776b32d3
public int reverse(int x) { int y=0; while(x!=0 && y*10+x%10<Integer.MAX_VALUE && y*10+x%10>Integer.MIN_VALUE) { y = y*10+x%10; x = x/10; } return y; }
9e392b90-b001-44ff-80a6-a29af6788932
public boolean isPalindrome(int x) { if(x == reverse(x) && x>=0) return true; return false; }
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public int divide(int dividend, int divisor) { if(divisor == 0) return 0; int res = 0; int loop = 0; boolean sign = ((dividend>0&&divisor<0) || (dividend<0&&divisor>0)) ; int newdividend = dividend>0?-1*dividend:dividend; int newdivisor = divisor>0?-1*divisor:divisor; ...
347c67a6-9d85-4124-b3a1-8f3a44d1c9a2
public int singleNumber2(int[] A) { HashMap<Integer, Integer> rec = new HashMap<Integer, Integer>(); for(int a:A) { if(!rec.containsKey(a)) rec.put(a, 1); else if(rec.get(a)<2) rec.put(a, rec.get(a)+1); else rec.remove(a); } return (int) rec.keySet().toArray()[0]; }
b6472c2d-df00-432d-9d05-3e7f04bf4560
public ArrayList<Integer> grayCode(int n) { ArrayList<Integer> res = new ArrayList<Integer>(); ArrayList<String> tempres = new ArrayList<String>(); if(n==0){ res.add(0); return res; } for(int i=1; i<=n; i++) { int size = tempres.s...
8b28d68c-713f-4adf-8a71-92a22c444067
public int maxProfit3(int[] prices) { if(prices.length<2) return 0; int[] first = new int[prices.length]; int[] second = new int[prices.length]; int min=prices[0]; int max = prices[prices.length-1]; for(int i=1; i<prices.length; i++) { min = Math.min(mi...
47f7d8c2-524a-409c-9a47-8e3bf54007c9
ListNode(int x) { val = x; next = null; }
6a4d1f17-3a04-4d6f-b4a9-d6ccd26156d9
public boolean isPalindrome(ListNode head) { if(head==null || head.next==null) return true; ListNode cur = head; ListNode tail=null; while(cur!=null) { ListNode copy = new ListNode(cur.val); copy.next = tail; tail = copy; cur = cur.next; } cur = head; while(cur!=null) { if(cur.val!=...
eca0f2bc-030f-4321-8ea0-e430f731ae82
public ListNode partitionList(ListNode head, int val) { if(head==null || head.next==null) return head; ListNode dummy=new ListNode(-1); dummy.next = head; ListNode cur=head, prev = dummy; while(cur!=null) { if(cur.val>= val) { prev = cur; cur=cur.next; }else { if(cur==head) {...
3ea0a737-4166-4157-842d-8baf2204764a
public void deletenode (ListNode head) { if(head==null) return; if(head.next == null) return; head.val =head.next.val; head.next = head.next.next; return; }
7a04d18a-719b-4a76-b907-d914a341db15
public void removedup1(ListNode head) { if(head==null || head.next==null) return; HashSet<Integer> set = new HashSet<Integer>(); ListNode cur= head, pre=null; while(cur!=null) { if(!set.contains(cur.val)) { set.add(cur.val); pre = cur; } else { pre.next = cur.next; } cur=cur....
0c4753e3-6fe1-4283-bfe7-788002d48298
public void removedup(ListNode head) { if(head == null || head.next == null) return; ListNode curr = head; ListNode unique = head; while(unique!=null) { curr = unique; while(curr.next!=null) { if(curr.next.val==unique.val) { curr.next = curr.next.next; }else curr = curr.next; ...
2348be1a-d123-484a-bcde-d6bd0419ae54
public ListNode kthtoLast(ListNode head, int k) { if(head==null) return null; if(k==0) return head; ListNode p1 = head; ListNode p2 = head; while(k>0 && p1!=null) { p1=p1.next; k--; } if(k>0) return null; while(p1!=null) { p2=p2.next; p1=p1.next; } return p2; }
da74ffa5-72ae-4d46-921e-b2de9cb90f2f
public ListNode add(ListNode l1, ListNode l2) { ListNode c1 = l1; ListNode c2 = l2; ListNode dummy = new ListNode(-1); ListNode c3 = dummy; int carry = 0; while(c1!=null || c2!=null || carry>0) { int x = (c1==null?0:c1.val) + (c2==null?0:c2.val) + carry; ListNode t = new ListNode(x%10); carr...