contestId int64 0 1.01k | name stringlengths 2 58 | tags listlengths 0 11 | title stringclasses 523
values | time-limit stringclasses 8
values | memory-limit stringclasses 8
values | problem-description stringlengths 0 7.15k | input-specification stringlengths 0 2.05k | output-specification stringlengths 0 1.5k | demo-input listlengths 0 7 | demo-output listlengths 0 7 | note stringlengths 0 5.24k | test_cases listlengths 0 402 | timeConsumedMillis int64 0 8k | memoryConsumedBytes int64 0 537M | score float64 -1 3.99 | __index_level_0__ int64 0 621k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
814 | An express train to reveries | [
"constructive algorithms"
] | null | null | Sengoku still remembers the mysterious "colourful meteoroids" she discovered with Lala-chan when they were little. In particular, one of the nights impressed her deeply, giving her the illusion that all her fancies would be realized.
On that night, Sengoku constructed a permutation *p*1,<=*p*2,<=...,<=*p**n* of intege... | The first line of input contains a positive integer *n* (2<=β€<=*n*<=β€<=1<=000) β the length of Sengoku's permutation, being the length of both meteor outbursts at the same time.
The second line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=*n*) β the sequence of colours in the firs... | Output *n* space-separated integers *p*1,<=*p*2,<=...,<=*p**n*, denoting a possible permutation Sengoku could have had. If there are more than one possible answer, output any one of them.
Input guarantees that such permutation exists. | [
"5\n1 2 3 4 3\n1 2 5 4 5\n",
"5\n4 4 2 3 1\n5 4 5 3 1\n",
"4\n1 1 3 4\n1 4 3 4\n"
] | [
"1 2 5 4 3\n",
"5 4 2 3 1\n",
"1 2 3 4\n"
] | In the first sample, both 1,β2,β5,β4,β3 and 1,β2,β3,β4,β5 are acceptable outputs.
In the second sample, 5,β4,β2,β3,β1 is the only permutation to satisfy the constraints. | [
{
"input": "5\n1 2 3 4 3\n1 2 5 4 5",
"output": "1 2 5 4 3"
},
{
"input": "5\n4 4 2 3 1\n5 4 5 3 1",
"output": "5 4 2 3 1"
},
{
"input": "4\n1 1 3 4\n1 4 3 4",
"output": "1 2 3 4"
},
{
"input": "10\n1 2 3 4 7 6 7 8 9 10\n1 2 3 4 5 6 5 8 9 10",
"output": "1 2 3 4 5 6 7 8 9... | 93 | 0 | 0 | 538 | |
447 | DZY Loves Strings | [
"greedy",
"implementation"
] | null | null | DZY loves collecting special strings which only contain lowercase letters. For each lowercase letter *c* DZY knows its value *w**c*. For each special string *s*<==<=*s*1*s*2... *s*|*s*| (|*s*| is the length of the string) he represents its value with a function *f*(*s*), where
Now DZY has a string *s*. He wants to in... | The first line contains a single string *s*Β (1<=β€<=|*s*|<=β€<=103).
The second line contains a single integer *k*Β (0<=β€<=*k*<=β€<=103).
The third line contains twenty-six integers from *w**a* to *w**z*. Each such number is non-negative and doesn't exceed 1000. | Print a single integer β the largest possible value of the resulting string DZY could get. | [
"abc\n3\n1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1\n"
] | [
"41\n"
] | In the test sample DZY can obtain "abcbbc", *value*β=β1Β·1β+β2Β·2β+β3Β·2β+β4Β·2β+β5Β·2β+β6Β·2β=β41. | [
{
"input": "abc\n3\n1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1",
"output": "41"
},
{
"input": "mmzhr\n3\n443 497 867 471 195 670 453 413 579 466 553 881 847 642 269 996 666 702 487 209 257 741 974 133 519 453",
"output": "29978"
},
{
"input": "ajeeseerqnpaujubmajpibxrccazaawetyw... | 124 | 307,200 | 3 | 539 | |
913 | Modular Exponentiation | [
"implementation",
"math"
] | null | null | The following problem is well-known: given integers *n* and *m*, calculate
where 2*n*<==<=2Β·2Β·...Β·2 (*n* factors), and denotes the remainder of division of *x* by *y*.
You are asked to solve the "reverse" problem. Given integers *n* and *m*, calculate | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=108).
The second line contains a single integer *m* (1<=β€<=*m*<=β€<=108). | Output a single integerΒ β the value of . | [
"4\n42\n",
"1\n58\n",
"98765432\n23456789\n"
] | [
"10\n",
"0\n",
"23456789\n"
] | In the first example, the remainder of division of 42 by 2<sup class="upper-index">4</sup>β=β16 is equal to 10.
In the second example, 58 is divisible by 2<sup class="upper-index">1</sup>β=β2 without remainder, and the answer is 0. | [
{
"input": "4\n42",
"output": "10"
},
{
"input": "1\n58",
"output": "0"
},
{
"input": "98765432\n23456789",
"output": "23456789"
},
{
"input": "8\n88127381",
"output": "149"
},
{
"input": "32\n92831989",
"output": "92831989"
},
{
"input": "92831989\n25... | 561 | 46,796,800 | 3 | 541 | |
948 | Protect Sheep | [
"brute force",
"dfs and similar",
"graphs",
"implementation"
] | null | null | Bob is a farmer. He has a large pasture with many sheep. Recently, he has lost some of them due to wolf attacks. He thus decided to place some shepherd dogs in such a way that all his sheep are protected.
The pasture is a rectangle consisting of *R*<=Γ<=*C* cells. Each cell is either empty, contains a sheep, a wolf or... | First line contains two integers *R* (1<=β€<=*R*<=β€<=500) and *C* (1<=β€<=*C*<=β€<=500), denoting the number of rows and the numbers of columns respectively.
Each of the following *R* lines is a string consisting of exactly *C* characters, representing one row of the pasture. Here, 'S' means a sheep, 'W' a wolf and '.' a... | If it is impossible to protect all sheep, output a single line with the word "No".
Otherwise, output a line with the word "Yes". Then print *R* lines, representing the pasture after placing dogs. Again, 'S' means a sheep, 'W' a wolf, 'D' is a dog and '.' an empty space. You are not allowed to move, remove or add a she... | [
"6 6\n..S...\n..S.W.\n.S....\n..W...\n...W..\n......\n",
"1 2\nSW\n",
"5 5\n.S...\n...S.\nS....\n...S.\n.S...\n"
] | [
"Yes\n..SD..\n..SDW.\n.SD...\n.DW...\nDD.W..\n......\n",
"No\n",
"Yes\n.S...\n...S.\nS.D..\n...S.\n.S...\n"
] | In the first example, we can split the pasture into two halves, one containing wolves and one containing sheep. Note that the sheep at (2,1) is safe, as wolves cannot move diagonally.
In the second example, there are no empty spots to put dogs that would guard the lone sheep.
In the third example, there are no wolves... | [
{
"input": "1 2\nSW",
"output": "No"
},
{
"input": "10 10\n....W.W.W.\n.........S\n.S.S...S..\nW.......SS\n.W..W.....\n.W...W....\nS..S...S.S\n....W...S.\n..S..S.S.S\nSS.......S",
"output": "Yes\nDDDDWDWDWD\nDDDDDDDDDS\nDSDSDDDSDD\nWDDDDDDDSS\nDWDDWDDDDD\nDWDDDWDDDD\nSDDSDDDSDS\nDDDDWDDDSD\nDDSD... | 31 | 0 | 0 | 542 | |
808 | Tea Party | [
"constructive algorithms",
"greedy",
"sortings"
] | null | null | Polycarp invited all his friends to the tea party to celebrate the holiday. He has *n* cups, one for each of his *n* friends, with volumes *a*1,<=*a*2,<=...,<=*a**n*. His teapot stores *w* milliliters of tea (*w*<=β€<=*a*1<=+<=*a*2<=+<=...<=+<=*a**n*). Polycarp wants to pour tea in cups in such a way that:
- Every cup... | The first line contains two integer numbers *n* and *w* (1<=β€<=*n*<=β€<=100, ).
The second line contains *n* numbers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=100). | Output how many milliliters of tea every cup should contain. If there are multiple answers, print any of them.
If it's impossible to pour all the tea and satisfy all conditions then output -1. | [
"2 10\n8 7\n",
"4 4\n1 1 1 1\n",
"3 10\n9 8 10\n"
] | [
"6 4 \n",
"1 1 1 1 \n",
"-1\n"
] | In the third example you should pour to the first cup at least 5 milliliters, to the second one at least 4, to the third one at least 5. It sums up to 14, which is greater than 10 milliliters available. | [
{
"input": "2 10\n8 7",
"output": "6 4 "
},
{
"input": "4 4\n1 1 1 1",
"output": "1 1 1 1 "
},
{
"input": "3 10\n9 8 10",
"output": "-1"
},
{
"input": "1 1\n1",
"output": "1 "
},
{
"input": "1 1\n2",
"output": "1 "
},
{
"input": "1 10\n20",
"output... | 61 | 0 | 0 | 543 | |
483 | Counterexample | [
"brute force",
"implementation",
"math",
"number theory"
] | null | null | Your friend has recently learned about coprime numbers. A pair of numbers {*a*,<=*b*} is called coprime if the maximum number that divides both *a* and *b* is equal to one.
Your friend often comes up with different statements. He has recently supposed that if the pair (*a*,<=*b*) is coprime and the pair (*b*,<=*c*) i... | The single line contains two positive space-separated integers *l*, *r* (1<=β€<=*l*<=β€<=*r*<=β€<=1018; *r*<=-<=*l*<=β€<=50). | Print three positive space-separated integers *a*, *b*, *c*Β β three distinct numbers (*a*,<=*b*,<=*c*) that form the counterexample. If there are several solutions, you are allowed to print any of them. The numbers must be printed in ascending order.
If the counterexample does not exist, print the single number -1. | [
"2 4\n",
"10 11\n",
"900000000000000009 900000000000000029\n"
] | [
"2 3 4\n",
"-1\n",
"900000000000000009 900000000000000010 900000000000000021\n"
] | In the first sample pair (2,β4) is not coprime and pairs (2,β3) and (3,β4) are.
In the second sample you cannot form a group of three distinct integers, so the answer is -1.
In the third sample it is easy to see that numbers 900000000000000009 and 900000000000000021 are divisible by three. | [
{
"input": "2 4",
"output": "2 3 4"
},
{
"input": "10 11",
"output": "-1"
},
{
"input": "900000000000000009 900000000000000029",
"output": "900000000000000009 900000000000000010 900000000000000021"
},
{
"input": "640097987171091791 640097987171091835",
"output": "64009798... | 31 | 0 | 0 | 545 | |
955 | Not simply beatiful strings | [
"implementation"
] | null | null | Let's call a string adorable if its letters can be realigned in such a way that they form two consequent groups of equal symbols (note that different groups must contain different symbols). For example, ababa is adorable (you can transform it to aaabb, where the first three letters form a group of *a*-s and others β a ... | The only line contains *s* (1<=β€<=|*s*|<=β€<=105) consisting of lowercase latin letters. | Print Β«YesΒ» if the string can be split according to the criteria above or Β«NoΒ» otherwise.
Each letter can be printed in arbitrary case. | [
"ababa\n",
"zzcxx\n",
"yeee\n"
] | [
"Yes\n",
"Yes\n",
"No\n"
] | In sample case two zzcxx can be split into subsequences zc and zxx each of which is adorable.
There's no suitable partition in sample case three. | [
{
"input": "ababa",
"output": "Yes"
},
{
"input": "zzcxx",
"output": "Yes"
},
{
"input": "yeee",
"output": "No"
},
{
"input": "a",
"output": "No"
},
{
"input": "bbab",
"output": "No"
},
{
"input": "abcd",
"output": "Yes"
},
{
"input": "abc"... | 155 | 4,198,400 | 0 | 547 | |
417 | Elimination | [
"dp",
"implementation",
"math"
] | null | null | The finalists of the "Russian Code Cup" competition in 2214 will be the participants who win in one of the elimination rounds.
The elimination rounds are divided into main and additional. Each of the main elimination rounds consists of *c* problems, the winners of the round are the first *n* people in the rating list.... | The first line contains two integers *c* and *d* (1<=β€<=*c*,<=*d*<=β€<=100)Β β the number of problems in the main and additional rounds, correspondingly. The second line contains two integers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=100). Finally, the third line contains an integer *k* (1<=β€<=*k*<=β€<=100)Β β the number of the pre... | In the first line, print a single integer β the minimum number of problems the jury needs to prepare. | [
"1 10\n7 2\n1\n",
"2 2\n2 1\n2\n"
] | [
"2\n",
"0\n"
] | none | [
{
"input": "1 10\n7 2\n1",
"output": "2"
},
{
"input": "2 2\n2 1\n2",
"output": "0"
},
{
"input": "8 9\n2 2\n3",
"output": "8"
},
{
"input": "5 5\n8 8\n7",
"output": "40"
},
{
"input": "1 8\n8 10\n8",
"output": "9"
},
{
"input": "5 7\n9 1\n8",
"out... | 93 | 0 | 0 | 549 | |
118 | String Task | [
"implementation",
"strings"
] | null | null | Petya started to attend programming lessons. On the first lesson his task was to write a simple program. The program was supposed to do the following: in the given string, consisting if uppercase and lowercase Latin letters, it:
- deletes all the vowels, - inserts a character "." before each consonant, - replaces ... | The first line represents input string of Petya's program. This string only consists of uppercase and lowercase Latin letters and its length is from 1 to 100, inclusive. | Print the resulting string. It is guaranteed that this string is not empty. | [
"tour\n",
"Codeforces\n",
"aBAcAba\n"
] | [
".t.r\n",
".c.d.f.r.c.s\n",
".b.c.b\n"
] | none | [
{
"input": "tour",
"output": ".t.r"
},
{
"input": "Codeforces",
"output": ".c.d.f.r.c.s"
},
{
"input": "aBAcAba",
"output": ".b.c.b"
},
{
"input": "obn",
"output": ".b.n"
},
{
"input": "wpwl",
"output": ".w.p.w.l"
},
{
"input": "ggdvq",
"output": "... | 92 | 0 | 3 | 550 | |
0 | none | [
"none"
] | null | null | You are given a string *s*, consisting of small Latin letters. Let's denote the length of the string as |*s*|. The characters in the string are numbered starting from 1.
Your task is to find out if it is possible to rearrange characters in string *s* so that for any prime number *p*<=β€<=|*s*| and for any integer *i* ... | The only line contains the initial string *s*, consisting of small Latin letters (1<=β€<=|*s*|<=β€<=1000). | If it is possible to rearrange the characters in the string so that the above-mentioned conditions were fulfilled, then print in the first line "YES" (without the quotes) and print on the second line one of the possible resulting strings. If such permutation is impossible to perform, then print the single string "NO". | [
"abc\n",
"abcd\n",
"xxxyxxx\n"
] | [
"YES\nabc\n",
"NO\n",
"YES\nxxxxxxy\n"
] | In the first sample any of the six possible strings will do: "abc", "acb", "bac", "bca", "cab" or "cba".
In the second sample no letter permutation will satisfy the condition at *p*β=β2 (*s*<sub class="lower-index">2</sub>β=β*s*<sub class="lower-index">4</sub>).
In the third test any string where character "y" doesn'... | [
{
"input": "abc",
"output": "YES\nabc"
},
{
"input": "abcd",
"output": "NO"
},
{
"input": "xxxyxxx",
"output": "YES\nxxxxxxy"
},
{
"input": "xxxjddyxduquybxdxx",
"output": "NO"
},
{
"input": "jjjjjjjjjjzjjjjjjjjjjjjjjjj",
"output": "YES\njjjjjjjjjjjjjjjjjjjjjj... | 30 | 0 | -1 | 551 | |
928 | Login Verification | [
"*special",
"strings"
] | null | null | When registering in a social network, users are allowed to create their own convenient login to make it easier to share contacts, print it on business cards, etc.
Login is an arbitrary sequence of lower and uppercase latin letters, digits and underline symbols (Β«_Β»). However, in order to decrease the number of frauds ... | The first line contains a non-empty string *s* consisting of lower and uppercase latin letters, digits and underline symbols (Β«_Β») with length not exceeding 50 Β β the login itself.
The second line contains a single integer *n* (1<=β€<=*n*<=β€<=1<=000)Β β the number of existing logins.
The next *n* lines describe the exi... | Print Β«YesΒ» (without quotes), if user can register via this login, i.e. none of the existing logins is similar with it.
Otherwise print Β«NoΒ» (without quotes). | [
"1_wat\n2\n2_wat\nwat_1\n",
"000\n3\n00\nooA\noOo\n",
"_i_\n3\n__i_\n_1_\nI\n",
"La0\n3\n2a0\nLa1\n1a0\n",
"abc\n1\naBc\n",
"0Lil\n2\nLIL0\n0Ril\n"
] | [
"Yes\n",
"No\n",
"No\n",
"No\n",
"No\n",
"Yes\n"
] | In the second sample case the user wants to create a login consisting of three zeros. It's impossible due to collision with the third among the existing.
In the third sample case the new login is similar with the second one. | [
{
"input": "1_wat\n2\n2_wat\nwat_1",
"output": "Yes"
},
{
"input": "000\n3\n00\nooA\noOo",
"output": "No"
},
{
"input": "_i_\n3\n__i_\n_1_\nI",
"output": "No"
},
{
"input": "La0\n3\n2a0\nLa1\n1a0",
"output": "No"
},
{
"input": "abc\n1\naBc",
"output": "No"
}... | 77 | 5,632,000 | 3 | 553 | |
846 | Chemistry in Berland | [
"dfs and similar",
"greedy",
"trees"
] | null | null | Igor is a post-graduate student of chemistry faculty in Berland State University (BerSU). He needs to conduct a complicated experiment to write his thesis, but laboratory of BerSU doesn't contain all the materials required for this experiment.
Fortunately, chemical laws allow material transformations (yes, chemistry i... | The first line contains one integer number *n* (1<=β€<=*n*<=β€<=105) β the number of materials discovered by Berland chemists.
The second line contains *n* integer numbers *b*1,<=*b*2... *b**n* (1<=β€<=*b**i*<=β€<=1012) β supplies of BerSU laboratory.
The third line contains *n* integer numbers *a*1,<=*a*2... *a**n* (1<=... | Print YES if it is possible to conduct an experiment. Otherwise print NO. | [
"3\n1 2 3\n3 2 1\n1 1\n1 1\n",
"3\n3 2 1\n1 2 3\n1 1\n1 2\n"
] | [
"YES\n",
"NO\n"
] | none | [
{
"input": "3\n1 2 3\n3 2 1\n1 1\n1 1",
"output": "YES"
},
{
"input": "3\n3 2 1\n1 2 3\n1 1\n1 2",
"output": "NO"
},
{
"input": "5\n2 1 1 2 3\n1 2 2 2 1\n1 2\n1 3\n2 4\n1 4",
"output": "NO"
},
{
"input": "10\n2 8 6 1 2 7 6 9 2 8\n4 9 4 3 5 2 9 3 7 3\n1 8\n2 8\n3 8\n4 10\n5 1\... | 1,279 | 268,390,400 | 0 | 558 | |
950 | Left-handers, Right-handers and Ambidexters | [
"implementation",
"math"
] | null | null | You are at a water bowling training. There are *l* people who play with their left hand, *r* people, who play with their right hand, and *a* ambidexters, who can play with left or right hand.
The coach decided to form a team of even number of players, exactly half of the players should play with their right hand, and ... | The only line contains three integers *l*, *r* and *a* (0<=β€<=*l*,<=*r*,<=*a*<=β€<=100) β the number of left-handers, the number of right-handers and the number of ambidexters at the training. | Print a single even integerΒ β the maximum number of players in the team. It is possible that the team can only have zero number of players. | [
"1 4 2\n",
"5 5 5\n",
"0 2 0\n"
] | [
"6\n",
"14\n",
"0\n"
] | In the first example you can form a team of 6 players. You should take the only left-hander and two ambidexters to play with left hand, and three right-handers to play with right hand. The only person left can't be taken into the team.
In the second example you can form a team of 14 people. You have to take all five l... | [
{
"input": "1 4 2",
"output": "6"
},
{
"input": "5 5 5",
"output": "14"
},
{
"input": "0 2 0",
"output": "0"
},
{
"input": "30 70 34",
"output": "128"
},
{
"input": "89 32 24",
"output": "112"
},
{
"input": "89 44 77",
"output": "210"
},
{
... | 78 | 0 | -1 | 559 | |
214 | System of Equations | [
"brute force"
] | null | null | Furik loves math lessons very much, so he doesn't attend them, unlike Rubik. But now Furik wants to get a good mark for math. For that Ms. Ivanova, his math teacher, gave him a new task. Furik solved the task immediately. Can you?
You are given a system of equations:
You should count, how many there are pairs of int... | A single line contains two integers *n*,<=*m* (1<=β€<=*n*,<=*m*<=β€<=1000) β the parameters of the system. The numbers on the line are separated by a space. | On a single line print the answer to the problem. | [
"9 3\n",
"14 28\n",
"4 20\n"
] | [
"1\n",
"1\n",
"0\n"
] | In the first sample the suitable pair is integers (3,β0). In the second sample the suitable pair is integers (3,β5). In the third sample there is no suitable pair. | [
{
"input": "9 3",
"output": "1"
},
{
"input": "14 28",
"output": "1"
},
{
"input": "4 20",
"output": "0"
},
{
"input": "18 198",
"output": "1"
},
{
"input": "22 326",
"output": "1"
},
{
"input": "26 104",
"output": "1"
},
{
"input": "14 10"... | 186 | 0 | 0 | 561 | |
679 | Bear and Prime 100 | [
"constructive algorithms",
"interactive",
"math"
] | null | null | This is an interactive problem. In the output section below you will see the information about flushing the output.
Bear Limak thinks of some hidden numberΒ β an integer from interval [2,<=100]. Your task is to say if the hidden number is prime or composite.
Integer *x*<=><=1 is called prime if it has exactly two d... | After each query you should read one string from the input. It will be "yes" if the printed integer is a divisor of the hidden number, and "no" otherwise. | Up to 20 times you can ask a queryΒ β print an integer from interval [2,<=100] in one line. You have to both print the end-of-line character and flush the output. After flushing you should read a response from the input.
In any moment you can print the answer "prime" or "composite" (without the quotes). After that, flu... | [
"yes\nno\nyes\n",
"no\nyes\nno\nno\nno\n"
] | [
"2\n80\n5\ncomposite\n",
"58\n59\n78\n78\n2\nprime\n"
] | The hidden number in the first query is 30. In a table below you can see a better form of the provided example of the communication process.
<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/ea790051c34ea7d2761cd9b096412ca7c647a173.png" style="max-width: 100.0%;max-height: 100.0%;"/>
The hi... | [
{
"input": "30",
"output": "composite 4"
},
{
"input": "59",
"output": "prime 15"
},
{
"input": "2",
"output": "prime 16"
},
{
"input": "7",
"output": "prime 16"
},
{
"input": "9",
"output": "composite 3"
},
{
"input": "13",
"output": "prime 15"
... | 15 | 0 | 0 | 562 | |
373 | Collecting Beats is Fun | [
"implementation"
] | null | null | Cucumber boy is fan of Kyubeat, a famous music game.
Kyubeat has 16 panels for playing arranged in 4<=Γ<=4 table. When a panel lights up, he has to press that panel.
Each panel has a timing to press (the preffered time when a player should press it), and Cucumber boy is able to press at most *k* panels in a time with... | The first line contains a single integer *k* (1<=β€<=*k*<=β€<=5) β the number of panels Cucumber boy can press with his one hand.
Next 4 lines contain 4 characters each (digits from 1 to 9, or period) β table of panels. If a digit *i* was written on the panel, it means the boy has to press that panel in time *i*. If per... | Output "YES" (without quotes), if he is able to press all the panels in perfect timing. If not, output "NO" (without quotes). | [
"1\n.135\n1247\n3468\n5789\n",
"5\n..1.\n1111\n..1.\n..1.\n",
"1\n....\n12.1\n.2..\n.2..\n"
] | [
"YES\n",
"YES\n",
"NO\n"
] | In the third sample boy cannot press all panels in perfect timing. He can press all the panels in timing in time 1, but he cannot press the panels in time 2 in timing with his two hands. | [
{
"input": "1\n.135\n1247\n3468\n5789",
"output": "YES"
},
{
"input": "5\n..1.\n1111\n..1.\n..1.",
"output": "YES"
},
{
"input": "1\n....\n12.1\n.2..\n.2..",
"output": "NO"
},
{
"input": "1\n6981\n.527\n4163\n2345",
"output": "YES"
},
{
"input": "5\n9999\n9999\n99... | 109 | 0 | 3 | 564 | |
894 | QAQ | [
"brute force",
"dp"
] | null | null | "QAQ" is a word to denote an expression of crying. Imagine "Q" as eyes with tears and "A" as a mouth.
Now Diamond has given Bort a string consisting of only uppercase English letters of length *n*. There is a great number of "QAQ" in the string (Diamond is so cute!).
Bort wants to know how many subsequences "QAQ" are... | The only line contains a string of length *n* (1<=β€<=*n*<=β€<=100). It's guaranteed that the string only contains uppercase English letters. | Print a single integerΒ β the number of subsequences "QAQ" in the string. | [
"QAQAQYSYIOIWIN\n",
"QAQQQZZYNOIWIN\n"
] | [
"4\n",
"3\n"
] | In the first example there are 4 subsequences "QAQ": "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN", "QAQAQYSYIOIWIN". | [
{
"input": "QAQAQYSYIOIWIN",
"output": "4"
},
{
"input": "QAQQQZZYNOIWIN",
"output": "3"
},
{
"input": "QA",
"output": "0"
},
{
"input": "IAQVAQZLQBQVQFTQQQADAQJA",
"output": "24"
},
{
"input": "QQAAQASGAYAAAAKAKAQIQEAQAIAAIAQQQQQ",
"output": "378"
},
{
... | 0 | 0 | -1 | 567 | |
626 | Jerry's Protest | [
"brute force",
"combinatorics",
"dp",
"probabilities"
] | null | null | Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andrew and Jerry draw randomly without replacement from a jar containing *n* balls, each labeled with a distinct positive integer. Without looking, they hand their balls to Harry, who awards the point to... | The first line of input contains a single integer *n* (2<=β€<=*n*<=β€<=2000) β the number of balls in the jar.
The second line contains *n* integers *a**i* (1<=β€<=*a**i*<=β€<=5000) β the number written on the *i*th ball. It is guaranteed that no two balls have the same number. | Print a single real value β the probability that Jerry has a higher total, given that Andrew wins the first two rounds and Jerry wins the third. Your answer will be considered correct if its absolute or relative error does not exceed 10<=-<=6.
Namely: let's assume that your answer is *a*, and the answer of the jury i... | [
"2\n1 2\n",
"3\n1 2 10\n"
] | [
"0.0000000000\n",
"0.0740740741\n"
] | In the first case, there are only two balls. In the first two rounds, Andrew must have drawn the 2 and Jerry must have drawn the 1, and vice versa in the final round. Thus, Andrew's sum is 5 and Jerry's sum is 4, so Jerry never has a higher total.
In the second case, each game could've had three outcomes β 10β-β2, 10β... | [
{
"input": "2\n1 2",
"output": "0.0000000000"
},
{
"input": "3\n1 2 10",
"output": "0.0740740741"
},
{
"input": "3\n1 2 3",
"output": "0.0000000000"
},
{
"input": "4\n2 4 1 3",
"output": "0.0416666667"
},
{
"input": "11\n1 2 4 8 16 32 64 128 256 512 1024",
"ou... | 2,000 | 0 | 0 | 568 | |
965 | Paper Airplanes | [
"math"
] | null | null | To make a paper airplane, one has to use a rectangular piece of paper. From a sheet of standard size you can make $s$ airplanes.
A group of $k$ people decided to make $n$ airplanes each. They are going to buy several packs of paper, each of them containing $p$ sheets, and then distribute the sheets between the people.... | The only line contains four integers $k$, $n$, $s$, $p$ ($1 \le k, n, s, p \le 10^4$)Β β the number of people, the number of airplanes each should make, the number of airplanes that can be made using one sheet and the number of sheets in one pack, respectively. | Print a single integerΒ β the minimum number of packs they should buy. | [
"5 3 2 3\n",
"5 3 100 1\n"
] | [
"4\n",
"5\n"
] | In the first sample they have to buy $4$ packs of paper: there will be $12$ sheets in total, and giving $2$ sheets to each person is enough to suit everyone's needs.
In the second sample they have to buy a pack for each person as they can't share sheets. | [
{
"input": "5 3 2 3",
"output": "4"
},
{
"input": "5 3 100 1",
"output": "5"
},
{
"input": "10000 10000 1 1",
"output": "100000000"
},
{
"input": "1 1 10000 10000",
"output": "1"
},
{
"input": "300 300 21 23",
"output": "196"
},
{
"input": "300 2 37 51... | 124 | 0 | 0 | 569 | |
556 | Case of the Zeros and Ones | [
"greedy"
] | null | null | Andrewid the Android is a galaxy-famous detective. In his free time he likes to think about strings containing zeros and ones.
Once he thought about a string of length *n* consisting of zeroes and ones. Consider the following operation: we choose any two adjacent positions in the string, and if one them contains 0, an... | First line of the input contains a single integer *n* (1<=β€<=*n*<=β€<=2Β·105), the length of the string that Andreid has.
The second line contains the string of length *n* consisting only from zeros and ones. | Output the minimum length of the string that may remain after applying the described operations several times. | [
"4\n1100\n",
"5\n01010\n",
"8\n11101111\n"
] | [
"0\n",
"1\n",
"6\n"
] | In the first sample test it is possible to change the string like the following: <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/10df55364c21c6e8d5da31b6ab6f6294c4fc26b3.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
In the second sample test it is possible to change the string like... | [
{
"input": "4\n1100",
"output": "0"
},
{
"input": "5\n01010",
"output": "1"
},
{
"input": "8\n11101111",
"output": "6"
},
{
"input": "1\n0",
"output": "1"
},
{
"input": "1\n1",
"output": "1"
},
{
"input": "2\n00",
"output": "2"
},
{
"input"... | 62 | 409,600 | 3 | 570 | |
280 | Maximum Xor Secondary | [
"data structures",
"implementation",
"two pointers"
] | null | null | Bike loves looking for the second maximum element in the sequence. The second maximum element in the sequence of distinct numbers *x*1,<=*x*2,<=...,<=*x**k* (*k*<=><=1) is such maximum element *x**j*, that the following inequality holds: .
The lucky number of the sequence of distinct positive integers *x*1,<=*x*2,<... | The first line contains integer *n* (1<=<<=*n*<=β€<=105). The second line contains *n* distinct integers *s*1,<=*s*2,<=...,<=*s**n* (1<=β€<=*s**i*<=β€<=109). | Print a single integer β the maximum lucky number among all lucky numbers of sequences *s*[*l*..*r*]. | [
"5\n5 2 1 4 3\n",
"5\n9 8 3 5 7\n"
] | [
"7\n",
"15\n"
] | For the first sample you can choose *s*[4..5]β=β{4,β3} and its lucky number is (4Β *xor*Β 3)β=β7. You can also choose *s*[1..2].
For the second sample you must choose *s*[2..5]β=β{8,β3,β5,β7}. | [
{
"input": "5\n5 2 1 4 3",
"output": "7"
},
{
"input": "5\n9 8 3 5 7",
"output": "15"
},
{
"input": "10\n76969694 71698884 32888447 31877010 65564584 87864180 7850891 1505323 17879621 15722446",
"output": "128869996"
},
{
"input": "10\n4547989 39261040 94929326 38131456 26174... | 62 | 102,400 | 0 | 576 | |
682 | Alyona and Numbers | [
"constructive algorithms",
"math",
"number theory"
] | null | null | After finishing eating her bun, Alyona came up with two integers *n* and *m*. She decided to write down two columns of integersΒ β the first column containing integers from 1 to *n* and the second containing integers from 1 to *m*. Now the girl wants to count how many pairs of integers she can choose, one from the first... | The only line of the input contains two integers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=1<=000<=000). | Print the only integerΒ β the number of pairs of integers (*x*,<=*y*) such that 1<=β€<=*x*<=β€<=*n*, 1<=β€<=*y*<=β€<=*m* and (*x*<=+<=*y*) is divisible by 5. | [
"6 12\n",
"11 14\n",
"1 5\n",
"3 8\n",
"5 7\n",
"21 21\n"
] | [
"14\n",
"31\n",
"1\n",
"5\n",
"7\n",
"88\n"
] | Following pairs are suitable in the first sample case:
- for *x*β=β1 fits *y* equal to 4 or 9; - for *x*β=β2 fits *y* equal to 3 or 8; - for *x*β=β3 fits *y* equal to 2, 7 or 12; - for *x*β=β4 fits *y* equal to 1, 6 or 11; - for *x*β=β5 fits *y* equal to 5 or 10; - for *x*β=β6 fits *y* equal to 4 or 9.
Only th... | [
{
"input": "6 12",
"output": "14"
},
{
"input": "11 14",
"output": "31"
},
{
"input": "1 5",
"output": "1"
},
{
"input": "3 8",
"output": "5"
},
{
"input": "5 7",
"output": "7"
},
{
"input": "21 21",
"output": "88"
},
{
"input": "10 15",
... | 46 | 0 | 0 | 579 | |
673 | Bear and Game | [
"implementation"
] | null | null | Bear Limak likes watching sports on TV. He is going to watch a game today. The game lasts 90 minutes and there are no breaks.
Each minute can be either interesting or boring. If 15 consecutive minutes are boring then Limak immediately turns TV off.
You know that there will be *n* interesting minutes *t*1,<=*t*2,<=...... | The first line of the input contains one integer *n* (1<=β€<=*n*<=β€<=90)Β β the number of interesting minutes.
The second line contains *n* integers *t*1,<=*t*2,<=...,<=*t**n* (1<=β€<=*t*1<=<<=*t*2<=<<=... *t**n*<=β€<=90), given in the increasing order. | Print the number of minutes Limak will watch the game. | [
"3\n7 20 88\n",
"9\n16 20 30 40 50 60 70 80 90\n",
"9\n15 20 30 40 50 60 70 80 90\n"
] | [
"35\n",
"15\n",
"90\n"
] | In the first sample, minutes 21,β22,β...,β35 are all boring and thus Limak will turn TV off immediately after the 35-th minute. So, he would watch the game for 35 minutes.
In the second sample, the first 15 minutes are boring.
In the third sample, there are no consecutive 15 boring minutes. So, Limak will watch the w... | [
{
"input": "3\n7 20 88",
"output": "35"
},
{
"input": "9\n16 20 30 40 50 60 70 80 90",
"output": "15"
},
{
"input": "9\n15 20 30 40 50 60 70 80 90",
"output": "90"
},
{
"input": "30\n6 11 12 15 22 24 30 31 32 33 34 35 40 42 44 45 47 50 53 54 57 58 63 67 75 77 79 81 83 88",
... | 108 | 0 | 0 | 581 | |
124 | The number of positions | [
"math"
] | null | null | Petr stands in line of *n* people, but he doesn't know exactly which position he occupies. He can say that there are no less than *a* people standing in front of him and no more than *b* people standing behind him. Find the number of different positions Petr can occupy. | The only line contains three integers *n*, *a* and *b* (0<=β€<=*a*,<=*b*<=<<=*n*<=β€<=100). | Print the single number β the number of the sought positions. | [
"3 1 1\n",
"5 2 3\n"
] | [
"2\n",
"3\n"
] | The possible positions in the first sample are: 2 and 3 (if we number the positions starting with 1).
In the second sample they are 3, 4 and 5. | [
{
"input": "3 1 1",
"output": "2"
},
{
"input": "5 2 3",
"output": "3"
},
{
"input": "5 4 0",
"output": "1"
},
{
"input": "6 5 5",
"output": "1"
},
{
"input": "9 4 3",
"output": "4"
},
{
"input": "11 4 6",
"output": "7"
},
{
"input": "13 8 ... | 62 | 0 | 0 | 582 | |
278 | New Problem | [
"brute force",
"strings"
] | null | null | Coming up with a new problem isn't as easy as many people think. Sometimes it is hard enough to name it. We'll consider a title original if it doesn't occur as a substring in any titles of recent Codeforces problems.
You've got the titles of *n* last problems β the strings, consisting of lowercase English letters. Yo... | The first line contains integer *n* (1<=β€<=*n*<=β€<=30) β the number of titles you've got to consider. Then follow *n* problem titles, one per line. Each title only consists of lowercase English letters (specifically, it doesn't contain any spaces) and has the length from 1 to 20, inclusive. | Print a string, consisting of lowercase English letters β the lexicographically minimum shortest original title. | [
"5\nthreehorses\ngoodsubstrings\nsecret\nprimematrix\nbeautifulyear\n",
"4\naa\nbdefghijklmn\nopqrstuvwxyz\nc\n"
] | [
"j\n",
"ab\n"
] | In the first sample the first 9 letters of the English alphabet (a, b, c, d, e, f, g, h, i) occur in the problem titles, so the answer is letter j.
In the second sample the titles contain 26 English letters, so the shortest original title cannot have length 1. Title aa occurs as a substring in the first title. | [
{
"input": "5\nthreehorses\ngoodsubstrings\nsecret\nprimematrix\nbeautifulyear",
"output": "j"
},
{
"input": "4\naa\nbdefghijklmn\nopqrstuvwxyz\nc",
"output": "ab"
},
{
"input": "1\na",
"output": "b"
},
{
"input": "1\nb",
"output": "a"
},
{
"input": "1\nz",
"o... | 92 | 102,400 | 0 | 583 | |
689 | Mike and Shortcuts | [
"dfs and similar",
"graphs",
"greedy",
"shortest paths"
] | null | null | Recently, Mike was very busy with studying for exams and contests. Now he is going to chill a bit by doing some sight seeing in the city.
City consists of *n* intersections numbered from 1 to *n*. Mike starts walking from his house located at the intersection number 1 and goes along some sequence of intersections. Wal... | The first line contains an integer *n* (1<=β€<=*n*<=β€<=200<=000)Β β the number of Mike's city intersection.
The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (*i*<=β€<=*a**i*<=β€<=*n* , , describing shortcuts of Mike's city, allowing to walk from intersection *i* to intersection *a**i* using only 1 unit of ... | In the only line print *n* integers *m*1,<=*m*2,<=...,<=*m**n*, where *m**i* denotes the least amount of total energy required to walk from intersection 1 to intersection *i*. | [
"3\n2 2 3\n",
"5\n1 2 3 4 5\n",
"7\n4 4 4 4 7 7 7\n"
] | [
"0 1 2 \n",
"0 1 2 3 4 \n",
"0 1 2 1 2 3 3 \n"
] | In the first sample case desired sequences are:
1:β1; *m*<sub class="lower-index">1</sub>β=β0;
2:β1,β2; *m*<sub class="lower-index">2</sub>β=β1;
3:β1,β3; *m*<sub class="lower-index">3</sub>β=β|3β-β1|β=β2.
In the second sample case the sequence for any intersection 1β<β*i* is always 1,β*i* and *m*<sub class="lowe... | [
{
"input": "3\n2 2 3",
"output": "0 1 2 "
},
{
"input": "5\n1 2 3 4 5",
"output": "0 1 2 3 4 "
},
{
"input": "7\n4 4 4 4 7 7 7",
"output": "0 1 2 1 2 3 3 "
},
{
"input": "98\n17 17 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 57 87 87... | 31 | 0 | 0 | 584 | |
263 | Beautiful Matrix | [
"implementation"
] | null | null | You've got a 5<=Γ<=5 matrix, consisting of 24 zeroes and a single number one. Let's index the matrix rows by numbers from 1 to 5 from top to bottom, let's index the matrix columns by numbers from 1 to 5 from left to right. In one move, you are allowed to apply one of the two following transformations to the matrix:
1.... | The input consists of five lines, each line contains five integers: the *j*-th integer in the *i*-th line of the input represents the element of the matrix that is located on the intersection of the *i*-th row and the *j*-th column. It is guaranteed that the matrix consists of 24 zeroes and a single number one. | Print a single integer β the minimum number of moves needed to make the matrix beautiful. | [
"0 0 0 0 0\n0 0 0 0 1\n0 0 0 0 0\n0 0 0 0 0\n0 0 0 0 0\n",
"0 0 0 0 0\n0 0 0 0 0\n0 1 0 0 0\n0 0 0 0 0\n0 0 0 0 0\n"
] | [
"3\n",
"1\n"
] | none | [
{
"input": "0 0 0 0 0\n0 0 0 0 1\n0 0 0 0 0\n0 0 0 0 0\n0 0 0 0 0",
"output": "3"
},
{
"input": "0 0 0 0 0\n0 0 0 0 0\n0 1 0 0 0\n0 0 0 0 0\n0 0 0 0 0",
"output": "1"
},
{
"input": "0 0 0 0 0\n0 0 0 0 0\n0 0 1 0 0\n0 0 0 0 0\n0 0 0 0 0",
"output": "0"
},
{
"input": "0 0 0 0 0... | 122 | 0 | 3 | 585 | |
775 | University Schedule | [
"*special"
] | null | null | In this problem your task is to come up with a week schedule of classes in university for professors and student groups. Consider that there are 6 educational days in week and maximum number of classes per educational day is 7 (classes numerated from 1 to 7 for each educational day).
It is known that in university *n*... | The first line contains three integers *n*, *m* and *a* (1<=β€<=*n*,<=*m*,<=*a*<=β€<=60) β the number of groups, the number of professors and the number of classrooms.
Each of the following *n* lines contains *m* integers from 0 to 24 β *j*-th number in *i*-th line equals to the number of classes with the professor *j* ... | In the first line print the minimized value of function *f*.
After that print blank line.
After that print the schedule for each student group in increasing order of group number. For each student group print 7 lines. Each line must contains 6 numbers. Let the number at *i*-th line and *j*-th column equals to *x*. If... | [
"3 3 1\n1 0 0\n0 1 0\n0 0 1\n",
"3 1 1\n1\n1\n1\n",
"5 7 10\n1 3 6 0 1 2 4\n0 3 0 6 5 1 4\n3 5 1 2 3 2 4\n2 3 1 1 4 1 2\n2 4 3 2 4 3 2\n"
] | [
"54\n\n1 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n\n0 0 0 0 0 0 \n2 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n\n0 0 0 0 0 0 \n0 0 0 0 0 0 \n3 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n0 0 0 0 0 0 \n",
"52\n\... | During the main part of the competition (one week) you solution will be judged on 100 preliminary tests. The first 10 preliminary tests are available for download by a link [http://assets.codeforces.com/files/vk/vkcup-2017-wr2-materials-v1.tar.gz](//assets.codeforces.com/files/vk/vkcup-2017-wr2-materials-v1.tar.gz).
A... | [] | 77 | 2,252,800 | -1 | 589 | |
584 | Olesya and Rodion | [
"math"
] | null | null | Olesya loves numbers consisting of *n* digits, and Rodion only likes numbers that are divisible by *t*. Find some number that satisfies both of them.
Your task is: given the *n* and *t* print an integer strictly larger than zero consisting of *n* digits that is divisible by *t*. If such number doesn't exist, print <=-... | The single line contains two numbers, *n* and *t* (1<=β€<=*n*<=β€<=100, 2<=β€<=*t*<=β€<=10) β the length of the number and the number it should be divisible by. | Print one such positive number without leading zeroes, β the answer to the problem, or <=-<=1, if such number doesn't exist. If there are multiple possible answers, you are allowed to print any of them. | [
"3 2\n"
] | [
"712"
] | none | [
{
"input": "3 2",
"output": "222"
},
{
"input": "2 2",
"output": "22"
},
{
"input": "4 3",
"output": "3333"
},
{
"input": "5 3",
"output": "33333"
},
{
"input": "10 7",
"output": "7777777777"
},
{
"input": "2 9",
"output": "99"
},
{
"input"... | 31 | 0 | 0 | 590 | |
651 | Beautiful Paintings | [
"greedy",
"sortings"
] | null | null | There are *n* pictures delivered for the new exhibition. The *i*-th painting has beauty *a**i*. We know that a visitor becomes happy every time he passes from a painting to a more beautiful one.
We are allowed to arranged pictures in any order. What is the maximum possible number of times the visitor may become happy ... | The first line of the input contains integer *n* (1<=β€<=*n*<=β€<=1000)Β β the number of painting.
The second line contains the sequence *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=1000), where *a**i* means the beauty of the *i*-th painting. | Print one integerΒ β the maximum possible number of neighbouring pairs, such that *a**i*<=+<=1<=><=*a**i*, after the optimal rearrangement. | [
"5\n20 30 10 50 40\n",
"4\n200 100 100 200\n"
] | [
"4\n",
"2\n"
] | In the first sample, the optimal order is: 10,β20,β30,β40,β50.
In the second sample, the optimal order is: 100,β200,β100,β200. | [
{
"input": "5\n20 30 10 50 40",
"output": "4"
},
{
"input": "4\n200 100 100 200",
"output": "2"
},
{
"input": "10\n2 2 2 2 2 2 2 2 2 2",
"output": "0"
},
{
"input": "1\n1000",
"output": "0"
},
{
"input": "2\n444 333",
"output": "1"
},
{
"input": "100\n... | 93 | 0 | 3 | 591 | |
234 | Weather | [
"dp",
"implementation"
] | null | null | Scientists say a lot about the problems of global warming and cooling of the Earth. Indeed, such natural phenomena strongly influence all life on our planet.
Our hero Vasya is quite concerned about the problems. He decided to try a little experiment and observe how outside daily temperature changes. He hung out a ther... | The first line contains a single integer *n* (2<=β€<=*n*<=β€<=105) β the number of days for which Vasya has been measuring the temperature.
The second line contains a sequence of *n* integers *t*1,<=*t*2,<=...,<=*t**n* (|*t**i*|<=β€<=109) β the sequence of temperature values. Numbers *t**i* are separated by single space... | Print a single integer β the answer to the given task. | [
"4\n-1 1 -2 1\n",
"5\n0 -1 1 2 -5\n"
] | [
"1\n",
"2\n"
] | Note to the first sample: there are two ways to change exactly one number so that the sequence met Vasya's condition. You can either replace the first number 1 by any negative number or replace the number -2 by any positive number. | [
{
"input": "4\n-1 1 -2 1",
"output": "1"
},
{
"input": "5\n0 -1 1 2 -5",
"output": "2"
},
{
"input": "6\n0 0 0 0 0 0",
"output": "6"
},
{
"input": "6\n-1 -2 -3 -4 5 6",
"output": "0"
},
{
"input": "8\n1 2 -1 0 10 2 12 13",
"output": "3"
},
{
"input": "... | 124 | 6,963,200 | 0 | 594 | |
804 | Find Amir | [
"constructive algorithms",
"greedy",
"math"
] | null | null | A few years ago Sajjad left his school and register to another one due to security reasons. Now he wishes to find Amir, one of his schoolmates and good friends.
There are *n* schools numerated from 1 to *n*. One can travel between each pair of them, to do so, he needs to buy a ticket. The ticker between schools *i* an... | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=105)Β β the number of schools. | Print single integer: the minimum cost of tickets needed to visit all schools. | [
"2\n",
"10\n"
] | [
"0\n",
"4\n"
] | In the first example we can buy a ticket between the schools that costs <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c67d72010e0498bfd065a6a38fdeaec90358507b.png" style="max-width: 100.0%;max-height: 100.0%;"/>. | [
{
"input": "2",
"output": "0"
},
{
"input": "10",
"output": "4"
},
{
"input": "43670",
"output": "21834"
},
{
"input": "4217",
"output": "2108"
},
{
"input": "17879",
"output": "8939"
},
{
"input": "31809",
"output": "15904"
},
{
"input": "... | 109 | 0 | 3 | 596 | |
593 | Beautiful Function | [
"constructive algorithms",
"math"
] | null | null | Every day Ruslan tried to count sheep to fall asleep, but this didn't help. Now he has found a more interesting thing to do. First, he thinks of some set of circles on a plane, and then tries to choose a beautiful set of points, such that there is at least one point from the set inside or on the border of each of the i... | The first line of the input contains number *n* (1<=β€<=*n*<=β€<=50)Β β the number of circles Ruslan thinks of. Next follow *n* lines, each of them containing three integers *x**i*, *y**i* and *r**i* (0<=β€<=*x**i*,<=*y**i*<=β€<=50, 2<=β€<=*r**i*<=β€<=50)Β β the coordinates of the center and the raduis of the *i*-th circle. | In the first line print a correct function *f*(*t*). In the second line print a correct function *g*(*t*). The set of the points (*x**t*<==<=*f*(*t*),<=*y**t*<==<=*g*(*t*)) (0<=β€<=*t*<=β€<=50) must satisfy the condition, that there is at least one point inside or on the border of each of the circles, Ruslan thinks of at... | [
"3\n0 10 4\n10 0 4\n20 10 4\n"
] | [
"t \nabs((t-10))"
] | Correct functions:
1. 101. (1+2)1. ((*t*-3)+(*t**4))1. *abs*((*t*-10))1. (*abs*((((23-*t*)*(*t***t*))+((45+12)*(*t***t*))))*((5**t*)+((12**t*)-13)))1. *abs*((*t*-(*abs*((*t**31))+14))))
Incorrect functions:
1. 3+5+7 (not enough brackets, it should be ((3+5)+7) or (3+(5+7))) 1. *abs*(*t*-3) (not enough brackets,... | [
{
"input": "3\n0 10 4\n10 0 4\n20 10 4",
"output": "(((0*((1-abs((t-0)))+abs((abs((t-0))-1))))+(5*((1-abs((t-1)))+abs((abs((t-1))-1)))))+(10*((1-abs((t-2)))+abs((abs((t-2))-1)))))\n(((5*((1-abs((t-0)))+abs((abs((t-0))-1))))+(0*((1-abs((t-1)))+abs((abs((t-1))-1)))))+(5*((1-abs((t-2)))+abs((abs((t-2))-1)))))"... | 93 | 0 | 0 | 597 | |
670 | Magic Powder - 1 | [
"binary search",
"brute force",
"implementation"
] | null | null | This problem is given in two versions that differ only by constraints. If you can solve this problem in large constraints, then you can just write a single solution to the both versions. If you find the problem too difficult in large constraints, you can write solution to the simplified version only.
Waking up in the ... | The first line of the input contains two positive integers *n* and *k* (1<=β€<=*n*,<=*k*<=β€<=1000)Β β the number of ingredients and the number of grams of the magic powder.
The second line contains the sequence *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=1000), where the *i*-th number is equal to the number of grams of... | Print the maximum number of cookies, which Apollinaria will be able to bake using the ingredients that she has and the magic powder. | [
"3 1\n2 1 4\n11 3 16\n",
"4 3\n4 3 5 6\n11 12 14 20\n"
] | [
"4\n",
"3\n"
] | In the first sample it is profitably for Apollinaria to make the existing 1 gram of her magic powder to ingredient with the index 2, then Apollinaria will be able to bake 4 cookies.
In the second sample Apollinaria should turn 1 gram of magic powder to ingredient with the index 1 and 1 gram of magic powder to ingredie... | [
{
"input": "3 1\n2 1 4\n11 3 16",
"output": "4"
},
{
"input": "4 3\n4 3 5 6\n11 12 14 20",
"output": "3"
},
{
"input": "10 926\n5 6 8 1 2 5 1 8 4 4\n351 739 998 725 953 970 906 691 707 1000",
"output": "137"
},
{
"input": "20 925\n7 3 1 2 1 3 1 3 1 2 3 1 5 8 1 3 7 3 4 2\n837 ... | 62 | 2,560,000 | 3 | 598 | |
764 | Timofey and cubes | [
"constructive algorithms",
"implementation"
] | null | null | Young Timofey has a birthday today! He got kit of *n* cubes as a birthday present from his parents. Every cube has a number *a**i*, which is written on it. Timofey put all the cubes in a row and went to unpack other presents.
In this time, Timofey's elder brother, Dima reordered the cubes using the following rule. Sup... | The first line contains single integer *n* (1<=β€<=*n*<=β€<=2Β·105)Β β the number of cubes.
The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (<=-<=109<=β€<=*a**i*<=β€<=109), where *a**i* is the number written on the *i*-th cube after Dima has changed their order. | Print *n* integers, separated by spacesΒ β the numbers written on the cubes in their initial order.
It can be shown that the answer is unique. | [
"7\n4 3 7 6 9 1 2\n",
"8\n6 1 4 2 5 6 9 2\n"
] | [
"2 3 9 6 7 1 4",
"2 1 6 2 5 4 9 6"
] | Consider the first sample.
1. At the begining row was [2, 3, 9, 6, 7, 1, 4]. 1. After first operation row was [4, 1, 7, 6, 9, 3, 2]. 1. After second operation row was [4, 3, 9, 6, 7, 1, 2]. 1. After third operation row was [4, 3, 7, 6, 9, 1, 2]. 1. At fourth operation we reverse just middle element, so nothing ha... | [
{
"input": "7\n4 3 7 6 9 1 2",
"output": "2 3 9 6 7 1 4"
},
{
"input": "8\n6 1 4 2 5 6 9 2",
"output": "2 1 6 2 5 4 9 6"
},
{
"input": "1\n1424",
"output": "1424"
},
{
"input": "9\n-7 9 -4 9 -6 11 15 2 -10",
"output": "-10 9 15 9 -6 11 -4 2 -7"
},
{
"input": "2\n2... | 421 | 17,817,600 | 3 | 600 | |
133 | HQ9+ | [
"implementation"
] | null | null | HQ9+ is a joke programming language which has only four one-character instructions:
- "H" prints "Hello, World!",- "Q" prints the source code of the program itself,- "9" prints the lyrics of "99 Bottles of Beer" song, - "+" increments the value stored in the internal accumulator.
Instructions "H" and "Q" are case-s... | The input will consist of a single line *p* which will give a program in HQ9+. String *p* will contain between 1 and 100 characters, inclusive. ASCII-code of each character of *p* will be between 33 (exclamation mark) and 126 (tilde), inclusive. | Output "YES", if executing the program will produce any output, and "NO" otherwise. | [
"Hi!\n",
"Codeforces\n"
] | [
"YES\n",
"NO\n"
] | In the first case the program contains only one instruction β "H", which prints "Hello, World!".
In the second case none of the program characters are language instructions. | [
{
"input": "Hi!",
"output": "YES"
},
{
"input": "Codeforces",
"output": "NO"
},
{
"input": "a+b=c",
"output": "NO"
},
{
"input": "hq-lowercase",
"output": "NO"
},
{
"input": "Q",
"output": "YES"
},
{
"input": "9",
"output": "YES"
},
{
"inpu... | 124 | 0 | 0 | 603 | |
748 | Santa Claus and a Place in a Class | [
"implementation",
"math"
] | null | null | Santa Claus is the first who came to the Christmas Olympiad, and he is going to be the first to take his place at a desk! In the classroom there are *n* lanes of *m* desks each, and there are two working places at each of the desks. The lanes are numbered from 1 to *n* from the left to the right, the desks in a lane ar... | The only line contains three integers *n*, *m* and *k* (1<=β€<=*n*,<=*m*<=β€<=10<=000, 1<=β€<=*k*<=β€<=2*nm*)Β β the number of lanes, the number of desks in each lane and the number of Santa Claus' place. | Print two integers: the number of lane *r*, the number of desk *d*, and a character *s*, which stands for the side of the desk Santa Claus. The character *s* should be "L", if Santa Clause should sit on the left, and "R" if his place is on the right. | [
"4 3 9\n",
"4 3 24\n",
"2 4 4\n"
] | [
"2 2 L\n",
"4 3 R\n",
"1 2 R\n"
] | The first and the second samples are shown on the picture. The green place corresponds to Santa Claus' place in the first example, the blue place corresponds to Santa Claus' place in the second example.
In the third sample there are two lanes with four desks in each, and Santa Claus has the fourth place. Thus, his pla... | [
{
"input": "4 3 9",
"output": "2 2 L"
},
{
"input": "4 3 24",
"output": "4 3 R"
},
{
"input": "2 4 4",
"output": "1 2 R"
},
{
"input": "3 10 24",
"output": "2 2 R"
},
{
"input": "10 3 59",
"output": "10 3 L"
},
{
"input": "10000 10000 160845880",
"... | 77 | 0 | 0 | 604 | |
415 | Mashmokh and Tokens | [
"binary search",
"greedy",
"implementation",
"math"
] | null | null | Bimokh is Mashmokh's boss. For the following *n* days he decided to pay to his workers in a new way. At the beginning of each day he will give each worker a certain amount of tokens. Then at the end of each day each worker can give some of his tokens back to get a certain amount of money. The worker can save the rest o... | The first line of input contains three space-separated integers *n*,<=*a*,<=*b*Β (1<=β€<=*n*<=β€<=105;Β 1<=β€<=*a*,<=*b*<=β€<=109). The second line of input contains *n* space-separated integers *x*1,<=*x*2,<=...,<=*x**n*Β (1<=β€<=*x**i*<=β€<=109). | Output *n* space-separated integers. The *i*-th of them is the number of tokens Mashmokh can save on the *i*-th day. | [
"5 1 4\n12 6 11 9 1\n",
"3 1 2\n1 2 3\n",
"1 1 1\n1\n"
] | [
"0 2 3 1 1 ",
"1 0 1 ",
"0 "
] | none | [
{
"input": "5 1 4\n12 6 11 9 1",
"output": "0 2 3 1 1 "
},
{
"input": "3 1 2\n1 2 3",
"output": "1 0 1 "
},
{
"input": "1 1 1\n1",
"output": "0 "
},
{
"input": "1 1 1000000000\n1000000000",
"output": "0 "
},
{
"input": "1 1 1000000000\n999999999",
"output": "9... | 156 | 4,403,200 | 0 | 606 | |
120 | Spiders | [
"dp",
"greedy",
"trees"
] | null | null | One day mum asked Petya to sort his toys and get rid of some of them. Petya found a whole box of toy spiders. They were quite dear to him and the boy didn't want to throw them away. Petya conjured a cunning plan: he will glue all the spiders together and attach them to the ceiling. Besides, Petya knows that the lower t... | The first input file line contains one integer *n* (1<=β€<=*n*<=β€<=100) β the number of spiders. Next *n* lines contain the descriptions of each spider: integer *n**i* (2<=β€<=*n**i*<=β€<=100) β the number of beads, then *n**i*<=-<=1 pairs of numbers denoting the numbers of the beads connected by threads. The beads that m... | Print a single number β the length of the required construction. | [
"1\n3 1 2 2 3\n",
"2\n3 1 2 1 3\n4 1 2 2 3 2 4\n",
"2\n5 1 2 2 3 3 4 3 5\n7 3 4 1 2 2 4 4 6 2 7 6 5\n"
] | [
"2\n",
"4\n",
"7\n"
] | none | [
{
"input": "1\n3 1 2 2 3",
"output": "2"
},
{
"input": "2\n3 1 2 1 3\n4 1 2 2 3 2 4",
"output": "4"
},
{
"input": "2\n5 1 2 2 3 3 4 3 5\n7 3 4 1 2 2 4 4 6 2 7 6 5",
"output": "7"
},
{
"input": "3\n3 1 2 2 3\n5 2 5 5 3 3 4 5 1\n9 6 5 5 9 4 8 4 7 2 1 2 6 2 4 6 3",
"output":... | 92 | 512,000 | 0 | 607 | |
863 | Quasi-palindrome | [
"brute force",
"implementation"
] | null | null | Let quasi-palindromic number be such number that adding some leading zeros (possible none) to it produces a palindromic string.
String *t* is called a palindrome, if it reads the same from left to right and from right to left.
For example, numbers 131 and 2010200 are quasi-palindromic, they can be transformed to str... | The first line contains one integer number *x* (1<=β€<=*x*<=β€<=109). This number is given without any leading zeroes. | Print "YES" if number *x* is quasi-palindromic. Otherwise, print "NO" (without quotes). | [
"131\n",
"320\n",
"2010200\n"
] | [
"YES\n",
"NO\n",
"YES\n"
] | none | [
{
"input": "131",
"output": "YES"
},
{
"input": "320",
"output": "NO"
},
{
"input": "2010200",
"output": "YES"
},
{
"input": "1",
"output": "YES"
},
{
"input": "1000000000",
"output": "YES"
},
{
"input": "999999999",
"output": "YES"
},
{
"i... | 62 | 0 | 3 | 608 | |
1,004 | Sonya and Hotels | [
"implementation"
] | null | null | Sonya decided that having her own hotel business is the best way of earning money because she can profit and rest wherever she wants.
The country where Sonya lives is an endless line. There is a city in each integer coordinate on this line. She has $n$ hotels, where the $i$-th hotel is located in the city with coordin... | The first line contains two integers $n$ and $d$ ($1\leq n\leq 100$, $1\leq d\leq 10^9$)Β β the number of Sonya's hotels and the needed minimum distance from a new hotel to all others.
The second line contains $n$ different integers in strictly increasing order $x_1, x_2, \ldots, x_n$ ($-10^9\leq x_i\leq 10^9$)Β β coord... | Print the number of cities where Sonya can build a new hotel so that the minimum distance from this hotel to all others is equal to $d$. | [
"4 3\n-3 2 9 16\n",
"5 2\n4 8 11 18 19\n"
] | [
"6\n",
"5\n"
] | In the first example, there are $6$ possible cities where Sonya can build a hotel. These cities have coordinates $-6$, $5$, $6$, $12$, $13$, and $19$.
In the second example, there are $5$ possible cities where Sonya can build a hotel. These cities have coordinates $2$, $6$, $13$, $16$, and $21$. | [
{
"input": "4 3\n-3 2 9 16",
"output": "6"
},
{
"input": "5 2\n4 8 11 18 19",
"output": "5"
},
{
"input": "10 10\n-67 -59 -49 -38 -8 20 41 59 74 83",
"output": "8"
},
{
"input": "10 10\n0 20 48 58 81 95 111 137 147 159",
"output": "9"
},
{
"input": "100 1\n0 1 2 3... | 109 | 0 | 3 | 609 | |
618 | Constellation | [
"geometry",
"implementation"
] | null | null | Cat Noku has obtained a map of the night sky. On this map, he found a constellation with *n* stars numbered from 1 to *n*. For each *i*, the *i*-th star is located at coordinates (*x**i*,<=*y**i*). No two stars are located at the same position.
In the evening Noku is going to take a look at the night sky. He would lik... | The first line of the input contains a single integer *n* (3<=β€<=*n*<=β€<=100<=000).
Each of the next *n* lines contains two integers *x**i* and *y**i* (<=-<=109<=β€<=*x**i*,<=*y**i*<=β€<=109).
It is guaranteed that no two stars lie at the same point, and there does not exist a line such that all stars lie on that line. | Print three distinct integers on a single lineΒ β the indices of the three points that form a triangle that satisfies the conditions stated in the problem.
If there are multiple possible answers, you may print any of them. | [
"3\n0 1\n1 0\n1 1\n",
"5\n0 0\n0 2\n2 0\n2 2\n1 1\n"
] | [
"1 2 3\n",
"1 3 5\n"
] | In the first sample, we can print the three indices in any order.
In the second sample, we have the following picture.
Note that the triangle formed by starts 1, 4 and 3 doesn't satisfy the conditions stated in the problem, as point 5 is not strictly outside of this triangle (it lies on it's border). | [
{
"input": "3\n0 1\n1 0\n1 1",
"output": "1 2 3"
},
{
"input": "5\n0 0\n0 2\n2 0\n2 2\n1 1",
"output": "1 3 5"
},
{
"input": "3\n819934317 939682125\n487662889 8614219\n-557136619 382982369",
"output": "1 3 2"
},
{
"input": "10\n25280705 121178189\n219147240 -570920213\n-8298... | 62 | 4,812,800 | 0 | 611 | |
918 | Radio Station | [
"implementation",
"strings"
] | null | null | As the guys fried the radio station facilities, the school principal gave them tasks as a punishment. Dustin's task was to add comments to nginx configuration for school's website. The school has *n* servers. Each server has a name and an ip (names aren't necessarily unique, but ips are). Dustin knows the ip and name o... | The first line of input contains two integers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=1000).
The next *n* lines contain the names and ips of the servers. Each line contains a string name, name of the server and a string ip, ip of the server, separated by space (1<=β€<=|*name*|<=β€<=10, *name* only consists of English lowercase... | Print *m* lines, the commands in the configuration file after Dustin did his task. | [
"2 2\nmain 192.168.0.2\nreplica 192.168.0.1\nblock 192.168.0.1;\nproxy 192.168.0.2;\n",
"3 5\ngoogle 8.8.8.8\ncodeforces 212.193.33.27\nserver 138.197.64.57\nredirect 138.197.64.57;\nblock 8.8.8.8;\ncf 212.193.33.27;\nunblock 8.8.8.8;\ncheck 138.197.64.57;\n"
] | [
"block 192.168.0.1; #replica\nproxy 192.168.0.2; #main\n",
"redirect 138.197.64.57; #server\nblock 8.8.8.8; #google\ncf 212.193.33.27; #codeforces\nunblock 8.8.8.8; #google\ncheck 138.197.64.57; #server\n"
] | none | [
{
"input": "2 2\nmain 192.168.0.2\nreplica 192.168.0.1\nblock 192.168.0.1;\nproxy 192.168.0.2;",
"output": "block 192.168.0.1; #replica\nproxy 192.168.0.2; #main"
},
{
"input": "3 5\ngoogle 8.8.8.8\ncodeforces 212.193.33.27\nserver 138.197.64.57\nredirect 138.197.64.57;\nblock 8.8.8.8;\ncf 212.193.3... | 139 | 102,400 | 3 | 612 | |
352 | Jeff and Periods | [
"implementation",
"sortings"
] | null | null | One day Jeff got hold of an integer sequence *a*1, *a*2, ..., *a**n* of length *n*. The boy immediately decided to analyze the sequence. For that, he needs to find all values of *x*, for which these conditions hold:
- *x* occurs in sequence *a*. - Consider all positions of numbers *x* in the sequence *a* (such *i*, ... | The first line contains integer *n* (1<=β€<=*n*<=β€<=105). The next line contains integers *a*1, *a*2, ..., *a**n* (1<=β€<=*a**i*<=β€<=105). The numbers are separated by spaces. | In the first line print integer *t* β the number of valid *x*. On each of the next *t* lines print two integers *x* and *p**x*, where *x* is current suitable value, *p**x* is the common difference between numbers in the progression (if *x* occurs exactly once in the sequence, *p**x* must equal 0). Print the pairs in th... | [
"1\n2\n",
"8\n1 2 1 3 1 2 1 5\n"
] | [
"1\n2 0\n",
"4\n1 2\n2 4\n3 0\n5 0\n"
] | In the first test 2 occurs exactly once in the sequence, ergo *p*<sub class="lower-index">2</sub>β=β0. | [
{
"input": "1\n2",
"output": "1\n2 0"
},
{
"input": "8\n1 2 1 3 1 2 1 5",
"output": "4\n1 2\n2 4\n3 0\n5 0"
},
{
"input": "3\n1 10 5",
"output": "3\n1 0\n5 0\n10 0"
},
{
"input": "4\n9 9 3 5",
"output": "3\n3 0\n5 0\n9 1"
},
{
"input": "6\n1 2 2 1 1 2",
"outpu... | 30 | 0 | 0 | 613 | |
808 | Card Game | [
"binary search",
"flows",
"graphs"
] | null | null | Digital collectible card games have become very popular recently. So Vova decided to try one of these.
Vova has *n* cards in his collection. Each of these cards is characterised by its power *p**i*, magic number *c**i* and level *l**i*. Vova wants to build a deck with total power not less than *k*, but magic numbers m... | The first line contains two integers *n* and *k* (1<=β€<=*n*<=β€<=100, 1<=β€<=*k*<=β€<=100000).
Then *n* lines follow, each of these lines contains three numbers that represent the corresponding card: *p**i*, *c**i* and *l**i* (1<=β€<=*p**i*<=β€<=1000, 1<=β€<=*c**i*<=β€<=100000, 1<=β€<=*l**i*<=β€<=*n*). | If Vova won't be able to build a deck with required power, print <=-<=1. Otherwise print the minimum level Vova has to reach in order to build a deck. | [
"5 8\n5 5 1\n1 5 4\n4 6 3\n1 12 4\n3 12 1\n",
"3 7\n4 4 1\n5 8 2\n5 3 3\n"
] | [
"4\n",
"2\n"
] | none | [
{
"input": "5 8\n5 5 1\n1 5 4\n4 6 3\n1 12 4\n3 12 1",
"output": "4"
},
{
"input": "3 7\n4 4 1\n5 8 2\n5 3 3",
"output": "2"
},
{
"input": "10 10\n3 3 6\n5 10 4\n4 7 9\n4 9 7\n1 9 4\n1 6 10\n4 10 1\n4 4 6\n2 7 2\n1 5 4",
"output": "4"
},
{
"input": "10 20\n9 4 10\n2 8 9\n9 1 ... | 1,777 | 4,710,400 | 3 | 614 | |
379 | New Year Candles | [
"implementation"
] | null | null | Vasily the Programmer loves romance, so this year he decided to illuminate his room with candles.
Vasily has *a* candles.When Vasily lights up a new candle, it first burns for an hour and then it goes out. Vasily is smart, so he can make *b* went out candles into a new candle. As a result, this new candle can be used ... | The single line contains two integers, *a* and *b* (1<=β€<=*a*<=β€<=1000;Β 2<=β€<=*b*<=β€<=1000). | Print a single integer β the number of hours Vasily can light up the room for. | [
"4 2\n",
"6 3\n"
] | [
"7\n",
"8\n"
] | Consider the first sample. For the first four hours Vasily lights up new candles, then he uses four burned out candles to make two new ones and lights them up. When these candles go out (stop burning), Vasily can make another candle. Overall, Vasily can light up the room for 7 hours. | [
{
"input": "4 2",
"output": "7"
},
{
"input": "6 3",
"output": "8"
},
{
"input": "1000 1000",
"output": "1001"
},
{
"input": "123 5",
"output": "153"
},
{
"input": "1000 2",
"output": "1999"
},
{
"input": "1 2",
"output": "1"
},
{
"input": ... | 46 | 0 | 0 | 615 | |
279 | Books | [
"binary search",
"brute force",
"implementation",
"two pointers"
] | null | null | When Valera has got some free time, he goes to the library to read some books. Today he's got *t* free minutes to read. That's why Valera took *n* books in the library and for each book he estimated the time he is going to need to read it. Let's number the books by integers from 1 to *n*. Valera needs *a**i* minutes to... | The first line contains two integers *n* and *t* (1<=β€<=*n*<=β€<=105;Β 1<=β€<=*t*<=β€<=109) β the number of books and the number of free minutes Valera's got. The second line contains a sequence of *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=104), where number *a**i* shows the number of minutes that the boy n... | Print a single integer β the maximum number of books Valera can read. | [
"4 5\n3 1 2 1\n",
"3 3\n2 2 3\n"
] | [
"3\n",
"1\n"
] | none | [
{
"input": "4 5\n3 1 2 1",
"output": "3"
},
{
"input": "3 3\n2 2 3",
"output": "1"
},
{
"input": "1 3\n5",
"output": "0"
},
{
"input": "1 10\n4",
"output": "1"
},
{
"input": "2 10\n6 4",
"output": "2"
},
{
"input": "6 10\n2 3 4 2 1 1",
"output": "4... | 0 | 0 | -1 | 616 | |
2 | Winner | [
"hashing",
"implementation"
] | A. Winner | 1 | 64 | The winner of the card game popular in Berland "Berlogging" is determined according to the following rules. If at the end of the game there is only one player with the maximum number of points, he is the winner. The situation becomes more difficult if the number of such players is more than one. During each round a pla... | The first line contains an integer number *n* (1<=<=β€<=<=*n*<=<=β€<=<=1000), *n* is the number of rounds played. Then follow *n* lines, containing the information about the rounds in "name score" format in chronological order, where name is a string of lower-case Latin letters with the length from 1 to 32, and score is ... | Print the name of the winner. | [
"3\nmike 3\nandrew 5\nmike 2\n",
"3\nandrew 3\nandrew 2\nmike 5\n"
] | [
"andrew\n",
"andrew\n"
] | none | [
{
"input": "3\nmike 3\nandrew 5\nmike 2",
"output": "andrew"
},
{
"input": "3\nandrew 3\nandrew 2\nmike 5",
"output": "andrew"
},
{
"input": "5\nkaxqybeultn -352\nmgochgrmeyieyskhuourfg -910\nkaxqybeultn 691\nmgochgrmeyieyskhuourfg -76\nkaxqybeultn -303",
"output": "kaxqybeultn"
},... | 92 | 0 | 0 | 619 |
282 | Bit++ | [
"implementation"
] | null | null | The classic programming language of Bitland is Bit++. This language is so peculiar and complicated.
The language is that peculiar as it has exactly one variable, called *x*. Also, there are two operations:
- Operation ++ increases the value of variable *x* by 1. - Operation -- decreases the value of variable *x* by... | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=150) β the number of statements in the programme.
Next *n* lines contain a statement each. Each statement contains exactly one operation (++ or --) and exactly one variable *x* (denoted as letter Β«XΒ»). Thus, there are no empty statements. The operation and th... | Print a single integer β the final value of *x*. | [
"1\n++X\n",
"2\nX++\n--X\n"
] | [
"1\n",
"0\n"
] | none | [
{
"input": "1\n++X",
"output": "1"
},
{
"input": "2\nX++\n--X",
"output": "0"
},
{
"input": "3\n++X\n++X\n++X",
"output": "3"
},
{
"input": "2\n--X\n--X",
"output": "-2"
},
{
"input": "5\n++X\n--X\n++X\n--X\n--X",
"output": "-1"
},
{
"input": "28\nX--\... | 46 | 0 | 3 | 621 | |
316 | Special Task | [
"greedy"
] | null | null | Special Agent Smart Beaver works in a secret research department of ABBYY. He's been working there for a long time and is satisfied with his job, as it allows him to eat out in the best restaurants and order the most expensive and exotic wood types there.
The content special agent has got an important task: to get th... | The first line contains string *s* β the hint to the safe code. String *s* consists of the following characters: ?, 0-9, A-J. It is guaranteed that the first character of string *s* doesn't equal to character 0.
The input limits for scoring 30 points are (subproblem A1):
- 1<=β€<=|*s*|<=β€<=5.
The input limits for s... | Print the number of codes that match the given hint. | [
"AJ\n",
"1?AA\n"
] | [
"81\n",
"100\n"
] | none | [
{
"input": "AJ",
"output": "81"
},
{
"input": "1?AA",
"output": "100"
},
{
"input": "?",
"output": "9"
},
{
"input": "7",
"output": "1"
},
{
"input": "A",
"output": "9"
},
{
"input": "BBB?",
"output": "90"
},
{
"input": "BC??",
"output"... | 92 | 0 | 0 | 623 | |
84 | Toy Army | [
"math",
"number theory"
] | A. Toy Army | 2 | 256 | The hero of our story, Valera, and his best friend Arcady are still in school, and therefore they spend all the free time playing turn-based strategy "GAGA: Go And Go Again". The gameplay is as follows.
There are two armies on the playing field each of which consists of *n* men (*n* is always even). The current playe... | The input data consist of a single integer *n* (2<=β€<=*n*<=β€<=108, *n* is even). Please note that before the game starts there are 2*n* soldiers on the fields. | Print a single number β a maximum total number of soldiers that could be killed in the course of the game in three turns. | [
"2\n",
"4\n"
] | [
"3\n",
"6\n"
] | The first sample test:
1) Valera's soldiers 1 and 2 shoot at Arcady's soldier 1.
2) Arcady's soldier 2 shoots at Valera's soldier 1.
3) Valera's soldier 1 shoots at Arcady's soldier 2.
There are 3 soldiers killed in total: Valera's soldier 1 and Arcady's soldiers 1 and 2. | [
{
"input": "2",
"output": "3"
},
{
"input": "4",
"output": "6"
},
{
"input": "6",
"output": "9"
},
{
"input": "8",
"output": "12"
},
{
"input": "10",
"output": "15"
},
{
"input": "140",
"output": "210"
},
{
"input": "500",
"output": "75... | 92 | 0 | 0 | 624 |
513 | Game | [
"constructive algorithms",
"math"
] | null | null | Two players play a simple game. Each player is provided with a box with balls. First player's box contains exactly *n*1 balls and second player's box contains exactly *n*2 balls. In one move first player can take from 1 to *k*1 balls from his box and throw them away. Similarly, the second player can take from 1 to *k*2... | The first line contains four integers *n*1,<=*n*2,<=*k*1,<=*k*2. All numbers in the input are from 1 to 50.
This problem doesn't have subproblems. You will get 3 points for the correct submission. | Output "First" if the first player wins and "Second" otherwise. | [
"2 2 1 2\n",
"2 1 1 1\n"
] | [
"Second\n",
"First\n"
] | Consider the first sample test. Each player has a box with 2 balls. The first player draws a single ball from his box in one move and the second player can either take 1 or 2 balls from his box in one move. No matter how the first player acts, the second player can always win if he plays wisely. | [
{
"input": "2 2 1 2",
"output": "Second"
},
{
"input": "2 1 1 1",
"output": "First"
},
{
"input": "5 7 4 1",
"output": "Second"
},
{
"input": "5 7 1 4",
"output": "Second"
},
{
"input": "5 7 10 10",
"output": "Second"
},
{
"input": "5 7 1 10",
"out... | 109 | 0 | 3 | 626 | |
177 | Rectangular Game | [
"number theory"
] | null | null | The Smart Beaver from ABBYY decided to have a day off. But doing nothing the whole day turned out to be too boring, and he decided to play a game with pebbles. Initially, the Beaver has *n* pebbles. He arranges them in *a* equal rows, each row has *b* pebbles (*a*<=><=1). Note that the Beaver must use all the pebble... | The single line of the input contains a single integer *n* β the initial number of pebbles the Smart Beaver has.
The input limitations for getting 30 points are:
- 2<=β€<=*n*<=β€<=50
The input limitations for getting 100 points are:
- 2<=β€<=*n*<=β€<=109 | Print a single number β the maximum possible result of the game. | [
"10\n",
"8\n"
] | [
"16\n",
"15\n"
] | Consider the first example (*c*<sub class="lower-index">1</sub>β=β10). The possible options for the game development are:
- Arrange the pebbles in 10 rows, one pebble per row. Then *c*<sub class="lower-index">2</sub>β=β1, and the game ends after the first move with the result of 11. - Arrange the pebbles in 5 rows, ... | [
{
"input": "10",
"output": "16"
},
{
"input": "8",
"output": "15"
},
{
"input": "4",
"output": "7"
},
{
"input": "36",
"output": "67"
},
{
"input": "32",
"output": "63"
},
{
"input": "46",
"output": "70"
},
{
"input": "6",
"output": "10... | 2,000 | 102,400 | 0 | 630 | |
774 | Bars | [
"*special",
"binary search"
] | null | null | Polycarp's workday lasts exactly $n$ minutes. He loves chocolate bars and can eat one bar in one minute. Today Polycarp has $k$ bars at the beginning of the workday.
In some minutes of the workday Polycarp has important things to do and in such minutes he is not able to eat a chocolate bar. In other minutes he can eit... | The first line contains two integers $n$ and $k$ ($2 \le n \le 200\,000$, $2 \le k \le n$) β the length of the workday in minutes and the number of chocolate bars, which Polycarp has in the beginning of the workday.
The second line contains the string with length $n$ consisting of zeros and ones. If the $i$-th symbol ... | Print the minimum possible break in minutes between eating chocolate bars. | [
"3 3\n010\n",
"8 3\n01010110\n"
] | [
"1\n",
"3\n"
] | In the first example Polycarp can not eat the chocolate bar in the second minute, so the time of the break equals to one minute.
In the second example Polycarp will eat bars in the minutes $1$ and $8$ anyway, also he needs to eat the chocolate bar in the minute $5$, so that the time of the maximum break will be equal ... | [
{
"input": "3 3\n010",
"output": "1"
},
{
"input": "8 3\n01010110",
"output": "3"
},
{
"input": "9 5\n001100110",
"output": "2"
},
{
"input": "2 2\n00",
"output": "0"
},
{
"input": "3 2\n010",
"output": "1"
},
{
"input": "3 2\n000",
"output": "1"
... | 2,000 | 1,843,200 | 0 | 635 | |
359 | Table | [
"constructive algorithms",
"greedy",
"implementation"
] | null | null | Simon has a rectangular table consisting of *n* rows and *m* columns. Simon numbered the rows of the table from top to bottom starting from one and the columns β from left to right starting from one. We'll represent the cell on the *x*-th row and the *y*-th column as a pair of numbers (*x*,<=*y*). The table corners are... | The first line contains exactly two integers *n*, *m* (3<=β€<=*n*,<=*m*<=β€<=50).
Next *n* lines contain the description of the table cells. Specifically, the *i*-th line contains *m* space-separated integers *a**i*1,<=*a**i*2,<=...,<=*a**im*. If *a**ij* equals zero, then cell (*i*,<=*j*) isn't good. Otherwise *a**ij* e... | Print a single number β the minimum number of operations Simon needs to carry out his idea. | [
"3 3\n0 0 0\n0 1 0\n0 0 0\n",
"4 3\n0 0 0\n0 0 1\n1 0 0\n0 0 0\n"
] | [
"4\n",
"2\n"
] | In the first sample, the sequence of operations can be like this:
- For the first time you need to choose cell (2,β2) and corner (1,β1). - For the second time you need to choose cell (2,β2) and corner (3,β3). - For the third time you need to choose cell (2,β2) and corner (3,β1). - For the fourth time you need to c... | [
{
"input": "3 3\n0 0 0\n0 1 0\n0 0 0",
"output": "4"
},
{
"input": "4 3\n0 0 0\n0 0 1\n1 0 0\n0 0 0",
"output": "2"
},
{
"input": "50 4\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 1 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0... | 77 | 5,529,600 | 3 | 636 | |
0 | none | [
"none"
] | null | null | This is an interactive problem.
Natasha is going to fly to Mars. Finally, Natasha sat in the rocket. She flies, flies... but gets bored. She wishes to arrive to Mars already! So she decides to find something to occupy herself. She couldn't think of anything better to do than to calculate the distance to the red planet... | The first line contains two integers $m$ and $n$ ($1 \le m \le 10^9$, $1 \le n \le 30$)Β β the maximum distance to Mars and the number of elements in the sequence $p$. | none | [
"5 2\n1\n-1\n-1\n1\n0\n"
] | [
"1\n2\n4\n5\n3\n"
] | In the example, hacking would look like this:
5 2 3
1 0
This means that the current distance to Mars is equal to $3$, Natasha knows that it does not exceed $5$, and the rocket answers in order: correctly, incorrectly, correctly, incorrectly ...
Really:
on the first query ($1$) the correct answer is $1$, the rocket... | [
{
"input": "5 2 3\n1 0",
"output": "3 queries, x=3"
},
{
"input": "1 1 1\n1",
"output": "1 queries, x=1"
},
{
"input": "3 2 3\n1 0",
"output": "4 queries, x=3"
},
{
"input": "6 3 5\n1 1 1",
"output": "5 queries, x=5"
},
{
"input": "10 4 3\n0 0 1 0",
"output": ... | 108 | 102,400 | -1 | 637 | |
414 | Mashmokh and Numbers | [
"constructive algorithms",
"number theory"
] | null | null | It's holiday. Mashmokh and his boss, Bimokh, are playing a game invented by Mashmokh.
In this game Mashmokh writes sequence of *n* distinct integers on the board. Then Bimokh makes several (possibly zero) moves. On the first move he removes the first and the second integer from from the board, on the second move he r... | The first line of input contains two space-separated integers *n*,<=*k*Β (1<=β€<=*n*<=β€<=105;Β 0<=β€<=*k*<=β€<=108). | If such sequence doesn't exist output -1 otherwise output *n* distinct space-separated integers *a*1,<=*a*2,<=...,<=*a**n*Β (1<=β€<=*a**i*<=β€<=109). | [
"5 2\n",
"5 3",
"7 2\n"
] | [
"1 2 3 4 5\n",
"2 4 3 7 1",
"-1\n"
] | *gcd*(*x*,β*y*) is greatest common divisor of *x* and *y*. | [
{
"input": "5 2",
"output": "1 2 3 4 5"
},
{
"input": "5 3",
"output": "2 4 5 6 7"
},
{
"input": "7 2",
"output": "-1"
},
{
"input": "1 1",
"output": "-1"
},
{
"input": "2 0",
"output": "-1"
},
{
"input": "1 10",
"output": "-1"
},
{
"input"... | 124 | 0 | 0 | 639 | |
299 | Ksusha the Squirrel | [
"brute force",
"implementation"
] | null | null | Ksusha the Squirrel is standing at the beginning of a straight road, divided into *n* sectors. The sectors are numbered 1 to *n*, from left to right. Initially, Ksusha stands in sector 1.
Ksusha wants to walk to the end of the road, that is, get to sector *n*. Unfortunately, there are some rocks on the road. We know ... | The first line contains two integers *n* and *k* (2<=β€<=*n*<=β€<=3Β·105,<=1<=β€<=*k*<=β€<=3Β·105). The next line contains *n* characters β the description of the road: the *i*-th character equals ".", if the *i*-th sector contains no rocks. Otherwise, it equals "#".
It is guaranteed that the first and the last characters e... | Print "YES" (without the quotes) if Ksusha can reach the end of the road, otherwise print "NO" (without the quotes). | [
"2 1\n..\n",
"5 2\n.#.#.\n",
"7 3\n.#.###.\n"
] | [
"YES\n",
"YES\n",
"NO\n"
] | none | [
{
"input": "2 1\n..",
"output": "YES"
},
{
"input": "5 2\n.#.#.",
"output": "YES"
},
{
"input": "7 3\n.#.###.",
"output": "NO"
},
{
"input": "2 200\n..",
"output": "YES"
},
{
"input": "2 1\n..",
"output": "YES"
},
{
"input": "2 2\n..",
"output": "Y... | 124 | 0 | 0 | 644 | |
629 | Far Relativeβs Birthday Cake | [
"brute force",
"combinatorics",
"constructive algorithms",
"implementation"
] | null | null | Door's family is going celebrate Famil Doors's birthday party. They love Famil Door so they are planning to make his birthday cake weird!
The cake is a *n*<=Γ<=*n* square consisting of equal squares with side length 1. Each square is either empty or consists of a single chocolate. They bought the cake and randomly sta... | In the first line of the input, you are given a single integer *n* (1<=β€<=*n*<=β€<=100)Β β the length of the side of the cake.
Then follow *n* lines, each containing *n* characters. Empty cells are denoted with '.', while cells that contain chocolates are denoted by 'C'. | Print the value of Famil Door's happiness, i.e. the number of pairs of chocolate pieces that share the same row or the same column. | [
"3\n.CC\nC..\nC.C\n",
"4\nCC..\nC..C\n.CC.\n.CC.\n"
] | [
"4\n",
"9\n"
] | If we number rows from top to bottom and columns from left to right, then, pieces that share the same row in the first sample are:
1. (1,β2) and (1,β3) 1. (3,β1) and (3,β3) 1. (2,β1) and (3,β1) 1. (1,β3) and (3,β3) | [
{
"input": "3\n.CC\nC..\nC.C",
"output": "4"
},
{
"input": "4\nCC..\nC..C\n.CC.\n.CC.",
"output": "9"
},
{
"input": "5\n.CCCC\nCCCCC\n.CCC.\nCC...\n.CC.C",
"output": "46"
},
{
"input": "7\n.CC..CC\nCC.C..C\nC.C..C.\nC...C.C\nCCC.CCC\n.CC...C\n.C.CCC.",
"output": "84"
},... | 140 | 307,200 | 3 | 645 | |
816 | Karen and Coffee | [
"binary search",
"data structures",
"implementation"
] | null | null | To stay woke and attentive during classes, Karen needs some coffee!
Karen, a coffee aficionado, wants to know the optimal temperature for brewing the perfect cup of coffee. Indeed, she has spent some time reading several recipe books, including the universally acclaimed "The Art of the Covfefe".
She knows *n* coffee ... | The first line of input contains three integers, *n*, *k* (1<=β€<=*k*<=β€<=*n*<=β€<=200000), and *q* (1<=β€<=*q*<=β€<=200000), the number of recipes, the minimum number of recipes a certain temperature must be recommended by to be admissible, and the number of questions Karen has, respectively.
The next *n* lines describe ... | For each question, output a single integer on a line by itself, the number of admissible integer temperatures between *a* and *b* degrees, inclusive. | [
"3 2 4\n91 94\n92 97\n97 99\n92 94\n93 97\n95 96\n90 100\n",
"2 1 1\n1 1\n200000 200000\n90 100\n"
] | [
"3\n3\n0\n4\n",
"0\n"
] | In the first test case, Karen knows 3 recipes.
1. The first one recommends brewing the coffee between 91 and 94 degrees, inclusive. 1. The second one recommends brewing the coffee between 92 and 97 degrees, inclusive. 1. The third one recommends brewing the coffee between 97 and 99 degrees, inclusive.
A temperatur... | [
{
"input": "3 2 4\n91 94\n92 97\n97 99\n92 94\n93 97\n95 96\n90 100",
"output": "3\n3\n0\n4"
},
{
"input": "2 1 1\n1 1\n200000 200000\n90 100",
"output": "0"
},
{
"input": "1 1 1\n1 1\n1 1",
"output": "1"
},
{
"input": "1 1 1\n200000 200000\n200000 200000",
"output": "1"
... | 998 | 85,913,600 | 3 | 646 | |
708 | Letters Cyclic Shift | [
"constructive algorithms",
"greedy",
"implementation",
"strings"
] | null | null | You are given a non-empty string *s* consisting of lowercase English letters. You have to pick exactly one non-empty substring of *s* and shift all its letters 'z' 'y' 'x' 'b' 'a' 'z'. In other words, each character is replaced with the previous character of English alphabet and 'a' is replaced with 'z'.
What is ... | The only line of the input contains the string *s* (1<=β€<=|*s*|<=β€<=100<=000) consisting of lowercase English letters. | Print the lexicographically minimum string that can be obtained from *s* by shifting letters of exactly one non-empty substring. | [
"codeforces\n",
"abacaba\n"
] | [
"bncdenqbdr\n",
"aaacaba\n"
] | String *s* is lexicographically smaller than some other string *t* of the same length if there exists some 1ββ€β*i*ββ€β|*s*|, such that *s*<sub class="lower-index">1</sub>β=β*t*<sub class="lower-index">1</sub>,β*s*<sub class="lower-index">2</sub>β=β*t*<sub class="lower-index">2</sub>,β...,β*s*<sub class="lower-index">*i*... | [
{
"input": "codeforces",
"output": "bncdenqbdr"
},
{
"input": "abacaba",
"output": "aaacaba"
},
{
"input": "babbbabaababbaa",
"output": "aabbbabaababbaa"
},
{
"input": "bcbacaabcababaccccaaaabacbbcbbaa",
"output": "abaacaabcababaccccaaaabacbbcbbaa"
},
{
"input": "... | 93 | 307,200 | 0 | 647 | |
235 | LCM Challenge | [
"number theory"
] | null | null | Some days ago, I learned the concept of LCM (least common multiple). I've played with it for several times and I want to make a big number with it.
But I also don't want to use many numbers, so I'll choose three positive integers (they don't have to be distinct) which are not greater than *n*. Can you help me to find ... | The first line contains an integer *n* (1<=β€<=*n*<=β€<=106) β the *n* mentioned in the statement. | Print a single integer β the maximum possible LCM of three not necessarily distinct positive integers that are not greater than *n*. | [
"9\n",
"7\n"
] | [
"504\n",
"210\n"
] | The least common multiple of some positive integers is the least positive integer which is multiple for each of them.
The result may become very large, 32-bit integer won't be enough. So using 64-bit integers is recommended.
For the last example, we can chose numbers 7, 6, 5 and the LCM of them is 7Β·6Β·5β=β210. It is ... | [
{
"input": "9",
"output": "504"
},
{
"input": "7",
"output": "210"
},
{
"input": "1",
"output": "1"
},
{
"input": "5",
"output": "60"
},
{
"input": "6",
"output": "60"
},
{
"input": "33",
"output": "32736"
},
{
"input": "21",
"output": ... | 560 | 30,515,200 | 3 | 649 | |
29 | Traffic Lights | [
"implementation"
] | B. Traffic Lights | 2 | 256 | A car moves from point A to point B at speed *v* meters per second. The action takes place on the X-axis. At the distance *d* meters from A there are traffic lights. Starting from time 0, for the first *g* seconds the green light is on, then for the following *r* seconds the red light is on, then again the green light ... | The first line contains integers *l*, *d*, *v*, *g*, *r* (1<=β€<=*l*,<=*d*,<=*v*,<=*g*,<=*r*<=β€<=1000,<=*d*<=<<=*l*) β the distance between A and B (in meters), the distance from A to the traffic lights, car's speed, the duration of green light and the duration of red light. | Output a single number β the minimum time that the car needs to get from point A to point B. Your output must have relative or absolute error less than 10<=-<=6. | [
"2 1 3 4 5\n",
"5 4 3 1 1\n"
] | [
"0.66666667\n",
"2.33333333\n"
] | none | [
{
"input": "2 1 3 4 5",
"output": "0.66666667"
},
{
"input": "5 4 3 1 1",
"output": "2.33333333"
},
{
"input": "862 33 604 888 704",
"output": "1.42715232"
},
{
"input": "458 251 49 622 472",
"output": "9.34693878"
},
{
"input": "772 467 142 356 889",
"output"... | 122 | 0 | -1 | 650 |
706 | Interesting drink | [
"binary search",
"dp",
"implementation"
] | null | null | Vasiliy likes to rest after a hard work, so you may often meet him in some bar nearby. As all programmers do, he loves the famous drink "Beecola", which can be bought in *n* different shops in the city. It's known that the price of one bottle in the shop *i* is equal to *x**i* coins.
Vasiliy plans to buy his favorite ... | The first line of the input contains a single integer *n* (1<=β€<=*n*<=β€<=100<=000)Β β the number of shops in the city that sell Vasiliy's favourite drink.
The second line contains *n* integers *x**i* (1<=β€<=*x**i*<=β€<=100<=000)Β β prices of the bottles of the drink in the *i*-th shop.
The third line contains a single i... | Print *q* integers. The *i*-th of them should be equal to the number of shops where Vasiliy will be able to buy a bottle of the drink on the *i*-th day. | [
"5\n3 10 8 6 11\n4\n1\n10\n3\n11\n"
] | [
"0\n4\n1\n5\n"
] | On the first day, Vasiliy won't be able to buy a drink in any of the shops.
On the second day, Vasiliy can buy a drink in the shops 1, 2, 3 and 4.
On the third day, Vasiliy can buy a drink only in the shop number 1.
Finally, on the last day Vasiliy can buy a drink in any shop. | [
{
"input": "5\n3 10 8 6 11\n4\n1\n10\n3\n11",
"output": "0\n4\n1\n5"
},
{
"input": "5\n868 987 714 168 123\n10\n424\n192\n795\n873\n117\n914\n735\n158\n631\n471",
"output": "2\n2\n3\n4\n0\n4\n3\n1\n2\n2"
},
{
"input": "3\n435 482 309\n7\n245\n241\n909\n745\n980\n29\n521",
"output": "... | 951 | 13,107,200 | 3 | 651 | |
719 | Vitya in the Countryside | [
"implementation"
] | null | null | Every summer Vitya comes to visit his grandmother in the countryside. This summer, he got a huge wart. Every grandma knows that one should treat warts when the moon goes down. Thus, Vitya has to catch the moment when the moon is down.
Moon cycle lasts 30 days. The size of the visible part of the moon (in Vitya's units... | The first line of the input contains a single integer *n* (1<=β€<=*n*<=β€<=92)Β β the number of consecutive days Vitya was watching the size of the visible part of the moon.
The second line contains *n* integers *a**i* (0<=β€<=*a**i*<=β€<=15)Β β Vitya's records.
It's guaranteed that the input data is consistent. | If Vitya can be sure that the size of visible part of the moon on day *n*<=+<=1 will be less than the size of the visible part on day *n*, then print "DOWN" at the only line of the output. If he might be sure that the size of the visible part will increase, then print "UP". If it's impossible to determine what exactly ... | [
"5\n3 4 5 6 7\n",
"7\n12 13 14 15 14 13 12\n",
"1\n8\n"
] | [
"UP\n",
"DOWN\n",
"-1\n"
] | In the first sample, the size of the moon on the next day will be equal to 8, thus the answer is "UP".
In the second sample, the size of the moon on the next day will be 11, thus the answer is "DOWN".
In the third sample, there is no way to determine whether the size of the moon on the next day will be 7 or 9, thus t... | [
{
"input": "5\n3 4 5 6 7",
"output": "UP"
},
{
"input": "7\n12 13 14 15 14 13 12",
"output": "DOWN"
},
{
"input": "1\n8",
"output": "-1"
},
{
"input": "44\n7 8 9 10 11 12 13 14 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 14 13 12 11 10",
"out... | 156 | 0 | 0 | 653 | |
761 | Dasha and friends | [
"brute force",
"implementation",
"math"
] | null | null | Running with barriers on the circle track is very popular in the country where Dasha lives, so no wonder that on her way to classes she saw the following situation:
The track is the circle with length *L*, in distinct points of which there are *n* barriers. Athlete always run the track in counterclockwise direction if... | The first line contains two integers *n* and *L* (1<=β€<=*n*<=β€<=50, *n*<=β€<=*L*<=β€<=100) β the number of barriers on a track and its length.
The second line contains *n* distinct integers in the ascending order β the distance from Kefa's start to each barrier in the order of its appearance. All integers are in the ra... | Print "YES" (without quotes), if Kefa and Sasha ran the coinciding tracks (it means that the position of all barriers coincides, if they start running from the same points on the track). Otherwise print "NO" (without quotes). | [
"3 8\n2 4 6\n1 5 7\n",
"4 9\n2 3 5 8\n0 1 3 6\n",
"2 4\n1 3\n1 2\n"
] | [
"YES\n",
"YES\n",
"NO\n"
] | The first test is analyzed in the statement. | [
{
"input": "3 8\n2 4 6\n1 5 7",
"output": "YES"
},
{
"input": "4 9\n2 3 5 8\n0 1 3 6",
"output": "YES"
},
{
"input": "2 4\n1 3\n1 2",
"output": "NO"
},
{
"input": "5 9\n0 2 5 6 7\n1 3 6 7 8",
"output": "YES"
},
{
"input": "5 60\n7 26 27 40 59\n14 22 41 42 55",
... | 77 | 0 | 0 | 654 | |
371 | Hamburgers | [
"binary search",
"brute force"
] | null | null | Polycarpus loves hamburgers very much. He especially adores the hamburgers he makes with his own hands. Polycarpus thinks that there are only three decent ingredients to make hamburgers from: a bread, sausage and cheese. He writes down the recipe of his favorite "Le Hamburger de Polycarpus" as a string of letters 'B' (... | The first line of the input contains a non-empty string that describes the recipe of "Le Hamburger de Polycarpus". The length of the string doesn't exceed 100, the string contains only letters 'B' (uppercase English B), 'S' (uppercase English S) and 'C' (uppercase English C).
The second line contains three integers *n... | Print the maximum number of hamburgers Polycarpus can make. If he can't make any hamburger, print 0. | [
"BBBSSC\n6 4 1\n1 2 3\n4\n",
"BBC\n1 10 1\n1 10 1\n21\n",
"BSC\n1 1 1\n1 1 3\n1000000000000\n"
] | [
"2\n",
"7\n",
"200000000001\n"
] | none | [
{
"input": "BBBSSC\n6 4 1\n1 2 3\n4",
"output": "2"
},
{
"input": "BBC\n1 10 1\n1 10 1\n21",
"output": "7"
},
{
"input": "BSC\n1 1 1\n1 1 3\n1000000000000",
"output": "200000000001"
},
{
"input": "B\n1 1 1\n1 1 1\n381",
"output": "382"
},
{
"input": "BSC\n3 5 6\n7... | 15 | 0 | 0 | 655 | |
182 | Common Divisors | [
"brute force",
"hashing",
"implementation",
"math",
"strings"
] | null | null | Vasya has recently learned at school what a number's divisor is and decided to determine a string's divisor. Here is what he came up with.
String *a* is the divisor of string *b* if and only if there exists a positive integer *x* such that if we write out string *a* consecutively *x* times, we get string *b*. For exam... | The first input line contains a non-empty string *s*1.
The second input line contains a non-empty string *s*2.
Lengths of strings *s*1 and *s*2 are positive and do not exceed 105. The strings only consist of lowercase Latin letters. | Print the number of common divisors of strings *s*1 and *s*2. | [
"abcdabcd\nabcdabcdabcdabcd\n",
"aaa\naa\n"
] | [
"2\n",
"1\n"
] | In first sample the common divisors are strings "abcd" and "abcdabcd".
In the second sample the common divisor is a single string "a". String "aa" isn't included in the answer as it isn't a divisor of string "aaa". | [
{
"input": "abcdabcd\nabcdabcdabcdabcd",
"output": "2"
},
{
"input": "aaa\naa",
"output": "1"
},
{
"input": "aaaaaaaaaaaaaaaaaaaaaaaaa\naaaaaaaaaaaaaaaaaaaaaaaaa",
"output": "3"
},
{
"input": "aaaaaaaaaaaaaa\naaaaaaaaaaaaaa",
"output": "4"
},
{
"input": "a\nb",
... | 280 | 9,113,600 | 3 | 656 | |
180 | Letter | [
"dp"
] | null | null | Patrick has just finished writing a message to his sweetheart Stacey when he noticed that the message didn't look fancy. Patrick was nervous while writing the message, so some of the letters there were lowercase and some of them were uppercase.
Patrick believes that a message is fancy if any uppercase letter stands to... | The only line of the input contains a non-empty string consisting of uppercase and lowercase letters. The string's length does not exceed 105. | Print a single number β the least number of actions needed to make the message fancy. | [
"PRuvetSTAaYA\n",
"OYPROSTIYAOPECHATALSYAPRIVETSTASYA\n",
"helloworld\n"
] | [
"5\n",
"0\n",
"0\n"
] | none | [
{
"input": "PRuvetSTAaYA",
"output": "5"
},
{
"input": "OYPROSTIYAOPECHATALSYAPRIVETSTASYA",
"output": "0"
},
{
"input": "helloworld",
"output": "0"
},
{
"input": "P",
"output": "0"
},
{
"input": "t",
"output": "0"
},
{
"input": "XdJ",
"output": "1... | 248 | 0 | 0 | 657 | |
523 | Statistics of Recompressing Videos | [
"*special",
"data structures",
"implementation"
] | null | null | A social network for dogs called DH (DogHouse) has *k* special servers to recompress uploaded videos of cute cats. After each video is uploaded, it should be recompressed on one (any) of the servers, and only after that it can be saved in the social network.
We know that each server takes one second to recompress a on... | The first line of the input contains integers *n* and *k* (1<=β€<=*n*,<=*k*<=β€<=5Β·105) β the number of videos and servers, respectively.
Next *n* lines contain the descriptions of the videos as pairs of integers *s**i*,<=*m**i* (1<=β€<=*s**i*,<=*m**i*<=β€<=109), where *s**i* is the time in seconds when the *i*-th video a... | Print *n* numbers *e*1,<=*e*2,<=...,<=*e**n*, where *e**i* is the time in seconds after the servers start working, when the *i*-th video will be recompressed. | [
"3 2\n1 5\n2 5\n3 5\n",
"6 1\n1 1000000000\n2 1000000000\n3 1000000000\n4 1000000000\n5 1000000000\n6 3\n"
] | [
"6\n7\n11\n",
"1000000001\n2000000001\n3000000001\n4000000001\n5000000001\n5000000004\n"
] | none | [
{
"input": "3 2\n1 5\n2 5\n3 5",
"output": "6\n7\n11"
},
{
"input": "6 1\n1 1000000000\n2 1000000000\n3 1000000000\n4 1000000000\n5 1000000000\n6 3",
"output": "1000000001\n2000000001\n3000000001\n4000000001\n5000000001\n5000000004"
},
{
"input": "1 1\n1 1",
"output": "2"
},
{
... | 62 | 409,600 | 0 | 658 | |
907 | Tic-Tac-Toe | [
"implementation"
] | null | null | Two bears are playing tic-tac-toe via mail. It's boring for them to play usual tic-tac-toe game, so they are a playing modified version of this game. Here are its rules.
The game is played on the following field.
Players are making moves by turns. At first move a player can put his chip in any cell of any small field... | First 11 lines contains descriptions of table with 9 rows and 9 columns which are divided into 9 small fields by spaces and empty lines. Each small field is described by 9 characters without spaces and empty lines. character "x" (ASCII-code 120) means that the cell is occupied with chip of the first player, character "... | Output the field in same format with characters "!" (ASCII-code 33) on positions where the current player can put his chip. All other cells should not be modified. | [
"... ... ...\n... ... ...\n... ... ...\n\n... ... ...\n... ... ...\n... x.. ...\n\n... ... ...\n... ... ...\n... ... ...\n6 4\n",
"xoo x.. x..\nooo ... ...\nooo ... ...\n\nx.. x.. x..\n... ... ...\n... ... ...\n\nx.. x.. x..\n... ... ...\n... ... ...\n7 4\n",
"o.. ... ...\n... ... ...\n... ... ...\n\n... xxx ..... | [
"... ... ... \n... ... ... \n... ... ... \n\n... ... ... \n... ... ... \n... x.. ... \n\n!!! ... ... \n!!! ... ... \n!!! ... ... \n\n",
"xoo x!! x!! \nooo !!! !!! \nooo !!! !!! \n\nx!! x!! x!! \n!!! !!! !!! \n!!! !!! !!! \n\nx!! x!! x!! \n!!! !!! !!! \n!!! !!! !!! \n\n",
"o!! !!! !!! \n!!! !!! !!! \n!!! !!! !!!... | In the first test case the first player made a move to lower left cell of central field, so the second player can put a chip only to cells of lower left field.
In the second test case the last move was done to upper left cell of lower central field, however all cells in upper left field are occupied, so the second pla... | [
{
"input": "... ... ...\n... ... ...\n... ... ...\n\n... ... ...\n... ... ...\n... x.. ...\n\n... ... ...\n... ... ...\n... ... ...\n6 4",
"output": "... ... ... \n... ... ... \n... ... ... \n\n... ... ... \n... ... ... \n... x.. ... \n\n!!! ... ... \n!!! ... ... \n!!! ... ... "
},
{
"input": "xoo x... | 62 | 5,632,000 | 3 | 659 | |
275 | Lights Out | [
"implementation"
] | null | null | Lenny is playing a game on a 3<=Γ<=3 grid of lights. In the beginning of the game all lights are switched on. Pressing any of the lights will toggle it and all side-adjacent lights. The goal of the game is to switch all the lights off. We consider the toggling as follows: if the light was switched on then it will be sw... | The input consists of three rows. Each row contains three integers each between 0 to 100 inclusive. The *j*-th number in the *i*-th row is the number of times the *j*-th light of the *i*-th row of the grid is pressed. | Print three lines, each containing three characters. The *j*-th character of the *i*-th line is "1" if and only if the corresponding light is switched on, otherwise it's "0". | [
"1 0 0\n0 0 0\n0 0 1\n",
"1 0 1\n8 8 8\n2 0 3\n"
] | [
"001\n010\n100\n",
"010\n011\n100\n"
] | none | [
{
"input": "1 0 0\n0 0 0\n0 0 1",
"output": "001\n010\n100"
},
{
"input": "1 0 1\n8 8 8\n2 0 3",
"output": "010\n011\n100"
},
{
"input": "13 85 77\n25 50 45\n65 79 9",
"output": "000\n010\n000"
},
{
"input": "96 95 5\n8 84 74\n67 31 61",
"output": "011\n011\n101"
},
{... | 77 | 204,800 | 3 | 660 | |
981 | Antipalindrome | [
"brute force",
"implementation",
"strings"
] | null | null | A string is a palindrome if it reads the same from the left to the right and from the right to the left. For example, the strings "kek", "abacaba", "r" and "papicipap" are palindromes, while the strings "abb" and "iq" are not.
A substring $s[l \ldots r]$ ($1<=\leq<=l<=\leq<=r<=\leq<=|s|$) of a string $s<==<=s_{1}s_{2}... | The first line contains a non-empty string $s$ with length at most $50$ characters, containing lowercase English letters only. | If there is such a substring in $s$ that is not a palindrome, print the maximum length of such a substring. Otherwise print $0$.
Note that there can be multiple longest substrings that are not palindromes, but their length is unique. | [
"mew\n",
"wuffuw\n",
"qqqqqqqq\n"
] | [
"3\n",
"5\n",
"0\n"
] | "mew" is not a palindrome, so the longest substring of it that is not a palindrome, is the string "mew" itself. Thus, the answer for the first example is $3$.
The string "uffuw" is one of the longest non-palindrome substrings (of length $5$) of the string "wuffuw", so the answer for the second example is $5$.
All sub... | [
{
"input": "mew",
"output": "3"
},
{
"input": "wuffuw",
"output": "5"
},
{
"input": "qqqqqqqq",
"output": "0"
},
{
"input": "ijvji",
"output": "4"
},
{
"input": "iiiiiii",
"output": "0"
},
{
"input": "wobervhvvkihcuyjtmqhaaigvvgiaahqmtjyuchikvvhvrebow"... | 109 | 0 | 3 | 661 | |
588 | Duff and Meat | [
"greedy"
] | null | null | Duff is addicted to meat! Malek wants to keep her happy for *n* days. In order to be happy in *i*-th day, she needs to eat exactly *a**i* kilograms of meat.
There is a big shop uptown and Malek wants to buy meat for her from there. In *i*-th day, they sell meat for *p**i* dollars per kilogram. Malek knows all numbers ... | The first line of input contains integer *n* (1<=β€<=*n*<=β€<=105), the number of days.
In the next *n* lines, *i*-th line contains two integers *a**i* and *p**i* (1<=β€<=*a**i*,<=*p**i*<=β€<=100), the amount of meat Duff needs and the cost of meat in that day. | Print the minimum money needed to keep Duff happy for *n* days, in one line. | [
"3\n1 3\n2 2\n3 1\n",
"3\n1 3\n2 1\n3 2\n"
] | [
"10\n",
"8\n"
] | In the first sample case: An optimal way would be to buy 1 kg on the first day, 2 kg on the second day and 3 kg on the third day.
In the second sample case: An optimal way would be to buy 1 kg on the first day and 5 kg (needed meat for the second and third day) on the second day. | [
{
"input": "3\n1 3\n2 2\n3 1",
"output": "10"
},
{
"input": "3\n1 3\n2 1\n3 2",
"output": "8"
},
{
"input": "1\n39 52",
"output": "2028"
},
{
"input": "2\n25 56\n94 17",
"output": "2998"
},
{
"input": "5\n39 21\n95 89\n73 90\n9 55\n85 32",
"output": "6321"
}... | 389 | 7,577,600 | 3 | 663 | |
940 | Our Tanya is Crying Out Loud | [
"dp",
"greedy"
] | null | null | Right now she actually isn't. But she will be, if you don't solve this problem.
You are given integers *n*, *k*, *A* and *B*. There is a number *x*, which is initially equal to *n*. You are allowed to perform two types of operations:
1. Subtract 1 from *x*. This operation costs you *A* coins. 1. Divide *x* by *k*.... | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=2Β·109).
The second line contains a single integer *k* (1<=β€<=*k*<=β€<=2Β·109).
The third line contains a single integer *A* (1<=β€<=*A*<=β€<=2Β·109).
The fourth line contains a single integer *B* (1<=β€<=*B*<=β€<=2Β·109). | Output a single integerΒ β the minimum amount of coins you have to pay to make *x* equal to 1. | [
"9\n2\n3\n1\n",
"5\n5\n2\n20\n",
"19\n3\n4\n2\n"
] | [
"6\n",
"8\n",
"12\n"
] | In the first testcase, the optimal strategy is as follows:
- Subtract 1 from *x* (9βββ8) paying 3 coins. - Divide *x* by 2 (8βββ4) paying 1 coin. - Divide *x* by 2 (4βββ2) paying 1 coin. - Divide *x* by 2 (2βββ1) paying 1 coin.
The total cost is 6 coins.
In the second test case the optimal strategy is to subtra... | [
{
"input": "9\n2\n3\n1",
"output": "6"
},
{
"input": "5\n5\n2\n20",
"output": "8"
},
{
"input": "19\n3\n4\n2",
"output": "12"
},
{
"input": "1845999546\n999435865\n1234234\n2323423",
"output": "1044857680578777"
},
{
"input": "1604353664\n1604353665\n9993432\n1",
... | 1,000 | 0 | 0 | 664 | |
268 | Buttons | [
"implementation",
"math"
] | null | null | Manao is trying to open a rather challenging lock. The lock has *n* buttons on it and to open it, you should press the buttons in a certain order to open the lock. When you push some button, it either stays pressed into the lock (that means that you've guessed correctly and pushed the button that goes next in the seque... | A single line contains integer *n* (1<=β€<=*n*<=β€<=2000) β the number of buttons the lock has. | In a single line print the number of times Manao has to push a button in the worst-case scenario. | [
"2\n",
"3\n"
] | [
"3\n",
"7\n"
] | Consider the first test sample. Manao can fail his first push and push the wrong button. In this case he will already be able to guess the right one with his second push. And his third push will push the second right button. Thus, in the worst-case scenario he will only need 3 pushes. | [
{
"input": "2",
"output": "3"
},
{
"input": "3",
"output": "7"
},
{
"input": "4",
"output": "14"
},
{
"input": "1",
"output": "1"
},
{
"input": "10",
"output": "175"
},
{
"input": "2000",
"output": "1333335000"
},
{
"input": "1747",
"ou... | 92 | 0 | 3 | 665 | |
108 | Palindromic Times | [
"implementation",
"strings"
] | A. Palindromic Times | 2 | 256 | Tattah is asleep if and only if Tattah is attending a lecture. This is a well-known formula among Tattah's colleagues.
On a Wednesday afternoon, Tattah was attending Professor HH's lecture. At 12:21, right before falling asleep, he was staring at the digital watch around Saher's wrist. He noticed that the digits on th... | The first and only line of the input starts with a string with the format "HH:MM" where "HH" is from "00" to "23" and "MM" is from "00" to "59". Both "HH" and "MM" have exactly two digits. | Print the palindromic time of day that comes soonest after the time given in the input. If the input time is palindromic, output the soonest palindromic time after the input time. | [
"12:21\n",
"23:59\n"
] | [
"13:31\n",
"00:00\n"
] | none | [
{
"input": "12:21",
"output": "13:31"
},
{
"input": "23:59",
"output": "00:00"
},
{
"input": "15:51",
"output": "20:02"
},
{
"input": "10:44",
"output": "11:11"
},
{
"input": "04:02",
"output": "04:40"
},
{
"input": "02:11",
"output": "02:20"
},
... | 280 | 409,600 | 3.929237 | 668 |
0 | none | [
"none"
] | null | null | A camera you have accidentally left in a desert has taken an interesting photo. The photo has a resolution of *n* pixels width, and each column of this photo is all white or all black. Thus, we can represent the photo as a sequence of *n* zeros and ones, where 0 means that the corresponding column is all white, and 1 m... | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=100<=000) β the width of the photo.
The second line contains a sequence of integers *a*1,<=*a*2,<=...,<=*a**n* (0<=β€<=*a**i*<=β€<=1) β the description of the photo. If *a**i* is zero, the *i*-th column is all black. If *a**i* is one, then the *i*-th column is ... | If the photo can be a photo of zebra, print "YES" (without quotes). Otherwise, print "NO".
You can print each letter in any case (upper or lower). | [
"9\n0 0 0 1 1 1 0 0 0\n",
"7\n0 0 0 1 1 1 1\n",
"5\n1 1 1 1 1\n",
"8\n1 1 1 0 0 0 1 1\n",
"9\n1 1 0 1 1 0 1 1 0\n"
] | [
"YES\n",
"NO\n",
"YES\n",
"NO\n",
"NO\n"
] | The first two examples are described in the statements.
In the third example all pixels are white, so the photo can be a photo of zebra.
In the fourth example the width of the first stripe is equal to three (white color), the width of the second stripe is equal to three (black), and the width of the third stripe is e... | [
{
"input": "9\n0 0 0 1 1 1 0 0 0",
"output": "YES"
},
{
"input": "7\n0 0 0 1 1 1 1",
"output": "NO"
},
{
"input": "5\n1 1 1 1 1",
"output": "YES"
},
{
"input": "8\n1 1 1 0 0 0 1 1",
"output": "NO"
},
{
"input": "9\n1 1 0 1 1 0 1 1 0",
"output": "NO"
},
{
... | 30 | 0 | 0 | 669 | |
111 | Petya and Coloring | [
"combinatorics",
"dp"
] | D. Petya and Coloring | 5 | 256 | Little Petya loves counting. He wants to count the number of ways to paint a rectangular checkered board of size *n*<=Γ<=*m* (*n* rows, *m* columns) in *k* colors. Besides, the coloring should have the following property: for any vertical line that passes along the grid lines and divides the board in two non-empty part... | The first line contains space-separated integers *n*, *m* and *k* (1<=β€<=*n*,<=*m*<=β€<=1000,<=1<=β€<=*k*<=β€<=106) β the board's vertical and horizontal sizes and the number of colors respectively. | Print the answer to the problem. As the answer can be quite a large number, you should print it modulo 109<=+<=7 (1000000007). | [
"2 2 1\n",
"2 2 2\n",
"3 2 2\n"
] | [
"1\n",
"8\n",
"40\n"
] | none | [
{
"input": "2 2 1",
"output": "1"
},
{
"input": "2 2 2",
"output": "8"
},
{
"input": "3 2 2",
"output": "40"
},
{
"input": "7 8 15",
"output": "422409918"
},
{
"input": "5 3 1",
"output": "1"
},
{
"input": "5 100 1",
"output": "1"
},
{
"inp... | 3,024 | 28,979,200 | -1 | 670 |
313 | Ilya and Bank Account | [
"implementation",
"number theory"
] | null | null | Ilya is a very clever lion, he lives in an unusual city ZooVille. In this city all the animals have their rights and obligations. Moreover, they even have their own bank accounts. The state of a bank account is an integer. The state of a bank account can be a negative number. This means that the owner of the account ow... | The single line contains integer *n* (10<=β€<=|*n*|<=β€<=109) β the state of Ilya's bank account. | In a single line print an integer β the maximum state of the bank account that Ilya can get. | [
"2230\n",
"-10\n",
"-100003\n"
] | [
"2230\n",
"0\n",
"-10000\n"
] | In the first test sample Ilya doesn't profit from using the present.
In the second test sample you can delete digit 1 and get the state of the account equal to 0. | [
{
"input": "2230",
"output": "2230"
},
{
"input": "-10",
"output": "0"
},
{
"input": "-100003",
"output": "-10000"
},
{
"input": "544883178",
"output": "544883178"
},
{
"input": "-847251738",
"output": "-84725173"
},
{
"input": "423654797",
"output... | 124 | 0 | 3 | 672 | |
935 | Fafa and his Company | [
"brute force",
"implementation"
] | null | null | Fafa owns a company that works on huge projects. There are *n* employees in Fafa's company. Whenever the company has a new project to start working on, Fafa has to divide the tasks of this project among all the employees.
Fafa finds doing this every time is very tiring for him. So, he decided to choose the best *l* em... | The input consists of a single line containing a positive integer *n* (2<=β€<=*n*<=β€<=105) β the number of employees in Fafa's company. | Print a single integer representing the answer to the problem. | [
"2\n",
"10\n"
] | [
"1\n",
"3\n"
] | In the second sample Fafa has 3 ways:
- choose only 1 employee as a team leader with 9 employees under his responsibility. - choose 2 employees as team leaders with 4 employees under the responsibility of each of them. - choose 5 employees as team leaders with 1 employee under the responsibility of each of them. | [
{
"input": "2",
"output": "1"
},
{
"input": "10",
"output": "3"
},
{
"input": "3",
"output": "1"
},
{
"input": "4",
"output": "2"
},
{
"input": "6",
"output": "3"
},
{
"input": "13",
"output": "1"
},
{
"input": "100000",
"output": "35"
... | 31 | 0 | 0 | 673 | |
26 | Almost Prime | [
"number theory"
] | A. Almost Prime | 2 | 256 | A number is called almost prime if it has exactly two distinct prime divisors. For example, numbers 6, 18, 24 are almost prime, while 4, 8, 9, 42 are not. Find the amount of almost prime numbers which are between 1 and *n*, inclusive. | Input contains one integer number *n* (1<=β€<=*n*<=β€<=3000). | Output the amount of almost prime numbers between 1 and *n*, inclusive. | [
"10\n",
"21\n"
] | [
"2\n",
"8\n"
] | none | [
{
"input": "10",
"output": "2"
},
{
"input": "21",
"output": "8"
},
{
"input": "1",
"output": "0"
},
{
"input": "2",
"output": "0"
},
{
"input": "4",
"output": "0"
},
{
"input": "3",
"output": "0"
},
{
"input": "8",
"output": "1"
},
... | 122 | 2,867,200 | -1 | 674 |
569 | Music | [
"implementation",
"math"
] | null | null | Little Lesha loves listening to music via his smartphone. But the smartphone doesn't have much memory, so Lesha listens to his favorite songs in a well-known social network InTalk.
Unfortunately, internet is not that fast in the city of Ekaterinozavodsk and the song takes a lot of time to download. But Lesha is quite ... | The single line contains three integers *T*,<=*S*,<=*q* (2<=β€<=*q*<=β€<=104, 1<=β€<=*S*<=<<=*T*<=β€<=105). | Print a single integerΒ β the number of times the song will be restarted. | [
"5 2 2\n",
"5 4 7\n",
"6 2 3\n"
] | [
"2\n",
"1\n",
"1\n"
] | In the first test, the song is played twice faster than it is downloaded, which means that during four first seconds Lesha reaches the moment that has not been downloaded, and starts the song again. After another two seconds, the song is downloaded completely, and thus, Lesha starts the song twice.
In the second test,... | [
{
"input": "5 2 2",
"output": "2"
},
{
"input": "5 4 7",
"output": "1"
},
{
"input": "6 2 3",
"output": "1"
},
{
"input": "2 1 2",
"output": "1"
},
{
"input": "2 1 3",
"output": "1"
},
{
"input": "2 1 10000",
"output": "1"
},
{
"input": "12... | 202 | 0 | 0 | 676 | |
75 | Life Without Zeros | [
"implementation"
] | A. Life Without Zeros | 2 | 256 | Can you imagine our life if we removed all zeros from it? For sure we will have many problems.
In this problem we will have a simple example if we removed all zeros from our life, it's the addition operation. Let's assume you are given this equation *a*<=+<=*b*<==<=*c*, where *a* and *b* are positive integers, and *c*... | The input will consist of two lines, the first line will contain the integer *a*, and the second line will contain the integer *b* which are in the equation as described above (1<=β€<=*a*,<=*b*<=β€<=109). There won't be any leading zeros in both. The value of *c* should be calculated as *c*<==<=*a*<=+<=*b*. | The output will be just one line, you should print "YES" if the equation will remain correct after removing all zeros, and print "NO" otherwise. | [
"101\n102\n",
"105\n106\n"
] | [
"YES\n",
"NO\n"
] | none | [
{
"input": "101\n102",
"output": "YES"
},
{
"input": "105\n106",
"output": "NO"
},
{
"input": "544\n397",
"output": "YES"
},
{
"input": "822\n280",
"output": "NO"
},
{
"input": "101\n413",
"output": "NO"
},
{
"input": "309\n139",
"output": "NO"
}... | 154 | 6,963,200 | 3.94853 | 679 |
441 | Valera and Antique Items | [
"implementation"
] | null | null | Valera is a collector. Once he wanted to expand his collection with exactly one antique item.
Valera knows *n* sellers of antiques, the *i*-th of them auctioned *k**i* items. Currently the auction price of the *j*-th object of the *i*-th seller is *s**ij*. Valera gets on well with each of the *n* sellers. He is perfec... | The first line contains two space-separated integers *n*,<=*v* (1<=β€<=*n*<=β€<=50;Β 104<=β€<=*v*<=β€<=106) β the number of sellers and the units of money the Valera has.
Then *n* lines follow. The *i*-th line first contains integer *k**i* (1<=β€<=*k**i*<=β€<=50) the number of items of the *i*-th seller. Then go *k**i* space... | In the first line, print integer *p* β the number of sellers with who Valera can make a deal.
In the second line print *p* space-separated integers *q*1,<=*q*2,<=...,<=*q**p* (1<=β€<=*q**i*<=β€<=*n*) β the numbers of the sellers with who Valera can make a deal. Print the numbers of the sellers in the increasing order. | [
"3 50000\n1 40000\n2 20000 60000\n3 10000 70000 190000\n",
"3 50000\n1 50000\n3 100000 120000 110000\n3 120000 110000 120000\n"
] | [
"3\n1 2 3\n",
"0\n\n"
] | In the first sample Valera can bargain with each of the sellers. He can outbid the following items: a 40000 item from the first seller, a 20000 item from the second seller, and a 10000 item from the third seller.
In the second sample Valera can not make a deal with any of the sellers, as the prices of all items in the... | [
{
"input": "3 50000\n1 40000\n2 20000 60000\n3 10000 70000 190000",
"output": "3\n1 2 3"
},
{
"input": "3 50000\n1 50000\n3 100000 120000 110000\n3 120000 110000 120000",
"output": "0"
},
{
"input": "2 100001\n1 895737\n1 541571",
"output": "0"
},
{
"input": "1 1000000\n1 100... | 31 | 0 | 0 | 680 | |
845 | Driving Test | [
"data structures",
"dp",
"greedy"
] | null | null | Polycarp has just attempted to pass the driving test. He ran over the straight road with the signs of four types.
- speed limit: this sign comes with a positive integer number β maximal speed of the car after the sign (cancel the action of the previous sign of this type); - overtake is allowed: this sign means that ... | The first line contains one integer number *n* (1<=β€<=*n*<=β€<=2Β·105) β number of events.
Each of the next *n* lines starts with integer *t* (1<=β€<=*t*<=β€<=6) β the type of the event.
An integer *s* (1<=β€<=*s*<=β€<=300) follows in the query of the first and the third type (if it is the query of first type, then it's ne... | Print the minimal number of road signs Polycarp should say he didn't notice, so that he would make no rule violations from his point of view. | [
"11\n1 100\n3 70\n4\n2\n3 120\n5\n3 120\n6\n1 150\n4\n3 300\n",
"5\n1 100\n3 200\n2\n4\n5\n",
"7\n1 20\n2\n6\n4\n6\n6\n2\n"
] | [
"2\n",
"0\n",
"2\n"
] | In the first example Polycarp should say he didn't notice the "speed limit" sign with the limit of 70 and the second "speed limit" sign with the limit of 120.
In the second example Polycarp didn't make any rule violation.
In the third example Polycarp should say he didn't notice both "no overtake allowed" that came a... | [
{
"input": "11\n1 100\n3 70\n4\n2\n3 120\n5\n3 120\n6\n1 150\n4\n3 300",
"output": "2"
},
{
"input": "5\n1 100\n3 200\n2\n4\n5",
"output": "0"
},
{
"input": "7\n1 20\n2\n6\n4\n6\n6\n2",
"output": "2"
},
{
"input": "1\n1 100",
"output": "0"
},
{
"input": "2\n1 100\... | 1,450 | 9,830,400 | 3 | 682 | |
593 | 2Char | [
"brute force",
"implementation"
] | null | null | Andrew often reads articles in his favorite magazine 2Char. The main feature of these articles is that each of them uses at most two distinct letters. Andrew decided to send an article to the magazine, but as he hasn't written any article, he just decided to take a random one from magazine 26Char. However, before sendi... | The first line of the input contains number *n* (1<=β€<=*n*<=β€<=100)Β β the number of words in the article chosen by Andrew. Following are *n* lines, each of them contains one word. All the words consist only of small English letters and their total length doesn't exceed 1000. The words are not guaranteed to be distinct,... | Print a single integerΒ β the maximum possible total length of words in Andrew's article. | [
"4\nabb\ncacc\naaa\nbbb\n",
"5\na\na\nbcbcb\ncdecdecdecdecdecde\naaaa\n"
] | [
"9",
"6"
] | In the first sample the optimal way to choose words is {'abb', 'aaa', 'bbb'}.
In the second sample the word 'cdecdecdecdecdecde' consists of three distinct letters, and thus cannot be used in the article. The optimal answer is {'a', 'a', 'aaaa'}. | [
{
"input": "4\nabb\ncacc\naaa\nbbb",
"output": "9"
},
{
"input": "5\na\na\nbcbcb\ncdecdecdecdecdecde\naaaa",
"output": "6"
},
{
"input": "1\na",
"output": "1"
},
{
"input": "2\nz\nz",
"output": "2"
},
{
"input": "5\nabcde\nfghij\nklmno\npqrst\nuvwxy",
"output"... | 46 | 0 | 0 | 684 | |
1,003 | Intense Heat | [
"brute force",
"implementation",
"math"
] | null | null | The heat during the last few days has been really intense. Scientists from all over the Berland study how the temperatures and weather change, and they claim that this summer is abnormally hot. But any scientific claim sounds a lot more reasonable if there are some numbers involved, so they have decided to actually cal... | The first line contains two integers $n$ and $k$ ($1 \le k \le n \le 5000$) β the number of days in the given period, and the minimum number of days in a segment we consider when calculating heat intensity value, respectively.
The second line contains $n$ integers $a_1$, $a_2$, ..., $a_n$ ($1 \le a_i \le 5000$) β the ... | Print one real number β the heat intensity value, i. e., the maximum of average temperatures over all segments of not less than $k$ consecutive days.
Your answer will be considered correct if the following condition holds: $|res - res_0| < 10^{-6}$, where $res$ is your answer, and $res_0$ is the answer given by the... | [
"4 3\n3 4 1 2\n"
] | [
"2.666666666666667\n"
] | none | [
{
"input": "4 3\n3 4 1 2",
"output": "2.666666666666667"
},
{
"input": "5 1\n3 10 9 10 6",
"output": "10.000000000000000"
},
{
"input": "5 2\n7 3 3 1 8",
"output": "5.000000000000000"
},
{
"input": "5 3\n1 7 6 9 1",
"output": "7.333333333333333"
},
{
"input": "5 4... | 4,000 | 0 | 0 | 685 | |
900 | Remove Extra One | [
"brute force",
"data structures",
"math"
] | null | null | You are given a permutation *p* of length *n*. Remove one element from permutation to make the number of records the maximum possible.
We remind that in a sequence of numbers *a*1,<=*a*2,<=...,<=*a**k* the element *a**i* is a record if for every integer *j* (1<=β€<=*j*<=<<=*i*) the following holds: *a**j*<=<<=*a*... | The first line contains the only integer *n* (1<=β€<=*n*<=β€<=105)Β β the length of the permutation.
The second line contains *n* integers *p*1,<=*p*2,<=...,<=*p**n* (1<=β€<=*p**i*<=β€<=*n*)Β β the permutation. All the integers are distinct. | Print the only integerΒ β the element that should be removed to make the number of records the maximum possible. If there are multiple such elements, print the smallest one. | [
"1\n1\n",
"5\n5 1 2 3 4\n"
] | [
"1\n",
"5\n"
] | In the first example the only element can be removed. | [
{
"input": "1\n1",
"output": "1"
},
{
"input": "5\n5 1 2 3 4",
"output": "5"
},
{
"input": "5\n4 3 5 1 2",
"output": "1"
},
{
"input": "9\n9 5 8 6 3 2 4 1 7",
"output": "9"
},
{
"input": "3\n3 2 1",
"output": "1"
},
{
"input": "7\n1 6 7 4 2 5 3",
"... | 93 | 7,065,600 | 0 | 688 | |
304 | Calendar | [
"brute force",
"implementation"
] | null | null | Calendars in widespread use today include the Gregorian calendar, which is the de facto international standard, and is used almost everywhere in the world for civil purposes. The Gregorian reform modified the Julian calendar's scheme of leap years as follows:
Every year that is exactly divisible by four is a leap yea... | The first two lines contain two dates, each date is in the format yyyy:mm:dd (1900<=β€<=*yyyy*<=β€<=2038 and yyyy:mm:dd is a legal date). | Print a single integer β the answer to the problem. | [
"1900:01:01\n2038:12:31\n",
"1996:03:09\n1991:11:12\n"
] | [
"50768\n",
"1579\n"
] | none | [
{
"input": "1900:01:01\n2038:12:31",
"output": "50768"
},
{
"input": "1996:03:09\n1991:11:12",
"output": "1579"
},
{
"input": "1999:12:31\n2000:02:29",
"output": "60"
},
{
"input": "1903:09:27\n1988:06:15",
"output": "30943"
},
{
"input": "1913:11:14\n1901:05:11",... | 184 | 5,734,400 | 0 | 689 | |
844 | Diversity | [
"greedy",
"implementation",
"strings"
] | null | null | Calculate the minimum number of characters you need to change in the string *s*, so that it contains at least *k* different letters, or print that it is impossible.
String *s* consists only of lowercase Latin letters, and it is allowed to change characters only to lowercase Latin letters too. | First line of input contains string *s*, consisting only of lowercase Latin letters (1<=β€<=|*s*|<=β€<=1000, |*s*| denotes the length of *s*).
Second line of input contains integer *k* (1<=β€<=*k*<=β€<=26). | Print single line with a minimum number of necessary changes, or the word Β«impossibleΒ» (without quotes) if it is impossible. | [
"yandex\n6\n",
"yahoo\n5\n",
"google\n7\n"
] | [
"0\n",
"1\n",
"impossible\n"
] | In the first test case string contains 6 different letters, so we don't need to change anything.
In the second test case string contains 4 different letters: {'*a*',β'*h*',β'*o*',β'*y*'}. To get 5 different letters it is necessary to change one occurrence of '*o*' to some letter, which doesn't occur in the string, for... | [
{
"input": "yandex\n6",
"output": "0"
},
{
"input": "yahoo\n5",
"output": "1"
},
{
"input": "google\n7",
"output": "impossible"
},
{
"input": "a\n1",
"output": "0"
},
{
"input": "z\n2",
"output": "impossible"
},
{
"input": "fwgfrwgkuwghfiruhewgirueguhe... | 61 | 0 | 0 | 690 | |
0 | none | [
"none"
] | null | null | Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular *w* mm <=Γ<= *h* mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how.
In order not to waste time, he decided to prac... | The first line contains three integers *w*,<=*h*,<=*n* (2<=β€<=*w*,<=*h*<=β€<=200<=000, 1<=β€<=*n*<=β€<=200<=000).
Next *n* lines contain the descriptions of the cuts. Each description has the form *H*Β *y* or *V*Β *x*. In the first case Leonid makes the horizontal cut at the distance *y* millimeters (1<=β€<=*y*<=β€<=*h*<=-<=... | After each cut print on a single line the area of the maximum available glass fragment in mm2. | [
"4 3 4\nH 2\nV 2\nV 3\nV 1\n",
"7 6 5\nH 4\nV 3\nV 5\nH 2\nV 1\n"
] | [
"8\n4\n4\n2\n",
"28\n16\n12\n6\n4\n"
] | Picture for the first sample test: | [
{
"input": "4 3 4\nH 2\nV 2\nV 3\nV 1",
"output": "8\n4\n4\n2"
},
{
"input": "7 6 5\nH 4\nV 3\nV 5\nH 2\nV 1",
"output": "28\n16\n12\n6\n4"
},
{
"input": "2 2 1\nV 1",
"output": "2"
},
{
"input": "2 2 1\nH 1",
"output": "2"
},
{
"input": "2 2 2\nV 1\nH 1",
"ou... | 62 | 0 | 0 | 691 | |
729 | Interview with Oleg | [
"implementation",
"strings"
] | null | null | Polycarp has interviewed Oleg and has written the interview down without punctuation marks and spaces to save time. Thus, the interview is now a string *s* consisting of *n* lowercase English letters.
There is a filler word ogo in Oleg's speech. All words that can be obtained from ogo by adding go several times to the... | The first line contains a positive integer *n* (1<=β€<=*n*<=β€<=100)Β β the length of the interview.
The second line contains the string *s* of length *n*, consisting of lowercase English letters. | Print the interview text after the replacement of each of the fillers with "***". It is allowed for the substring "***" to have several consecutive occurences. | [
"7\naogogob\n",
"13\nogogmgogogogo\n",
"9\nogoogoogo\n"
] | [
"a***b\n",
"***gmg***\n",
"*********\n"
] | The first sample contains one filler word ogogo, so the interview for printing is "a***b".
The second sample contains two fillers ogo and ogogogo. Thus, the interview is transformed to "***gmg***". | [
{
"input": "7\naogogob",
"output": "a***b"
},
{
"input": "13\nogogmgogogogo",
"output": "***gmg***"
},
{
"input": "9\nogoogoogo",
"output": "*********"
},
{
"input": "32\nabcdefogoghijklmnogoopqrstuvwxyz",
"output": "abcdef***ghijklmn***opqrstuvwxyz"
},
{
"input":... | 93 | 7,065,600 | 3 | 698 | |
300 | Array | [
"brute force",
"constructive algorithms",
"implementation"
] | null | null | Vitaly has an array of *n* distinct integers. Vitaly wants to divide this array into three non-empty sets so as the following conditions hold:
1. The product of all numbers in the first set is less than zero (<=<<=0). 1. The product of all numbers in the second set is greater than zero (<=><=0). 1. The produ... | The first line of the input contains integer *n* (3<=β€<=*n*<=β€<=100). The second line contains *n* space-separated distinct integers *a*1,<=*a*2,<=...,<=*a**n* (|*a**i*|<=β€<=103) β the array elements. | In the first line print integer *n*1 (*n*1<=><=0) β the number of elements in the first set. Then print *n*1 numbers β the elements that got to the first set.
In the next line print integer *n*2 (*n*2<=><=0) β the number of elements in the second set. Then print *n*2 numbers β the elements that got to the second... | [
"3\n-1 2 0\n",
"4\n-1 -2 -3 0\n"
] | [
"1 -1\n1 2\n1 0\n",
"1 -1\n2 -3 -2\n1 0\n"
] | none | [
{
"input": "3\n-1 2 0",
"output": "1 -1\n1 2\n1 0"
},
{
"input": "4\n-1 -2 -3 0",
"output": "1 -1\n2 -3 -2\n1 0"
},
{
"input": "5\n-1 -2 1 2 0",
"output": "1 -1\n2 1 2\n2 0 -2"
},
{
"input": "100\n-64 -51 -75 -98 74 -26 -1 -8 -99 -76 -53 -80 -43 -22 -100 -62 -34 -5 -65 -81 -1... | 216 | 20,172,800 | 0 | 700 | |
982 | Shark | [
"brute force",
"data structures",
"dsu",
"trees"
] | null | null | For long time scientists study the behavior of sharks. Sharks, as many other species, alternate short movements in a certain location and long movements between locations.
Max is a young biologist. For $n$ days he watched a specific shark, and now he knows the distance the shark traveled in each of the days. All the d... | The first line contains a single integer $n$ ($1 \leq n \leq 10^5$) β the number of days.
The second line contains $n$ distinct positive integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq 10^9$) β the distance traveled in each of the day. | Print a single integer $k$, such that
1. the shark was in each location the same number of days, 1. the number of locations is maximum possible satisfying the first condition, 1. $k$ is smallest possible satisfying the first and second conditions. | [
"8\n1 2 7 3 4 8 5 6\n",
"6\n25 1 2 3 14 36\n"
] | [
"7",
"2"
] | In the first example the shark travels inside a location on days $1$ and $2$ (first location), then on $4$-th and $5$-th days (second location), then on $7$-th and $8$-th days (third location). There are three locations in total.
In the second example the shark only moves inside a location on the $2$-nd day, so there ... | [
{
"input": "8\n1 2 7 3 4 8 5 6",
"output": "7"
},
{
"input": "6\n25 1 2 3 14 36",
"output": "2"
},
{
"input": "20\n1 20 2 19 3 18 4 17 5 16 6 15 7 14 8 13 9 12 10 11",
"output": "11"
},
{
"input": "7\n1 2 5 7 3 4 6",
"output": "5"
},
{
"input": "1\n1000000000",
... | 46 | 0 | 0 | 705 | |
31 | Worms Evolution | [
"implementation"
] | A. Worms Evolution | 2 | 256 | Professor Vasechkin is studying evolution of worms. Recently he put forward hypotheses that all worms evolve by division. There are *n* forms of worms. Worms of these forms have lengths *a*1, *a*2, ..., *a**n*. To prove his theory, professor needs to find 3 different forms that the length of the first form is equal to ... | The first line contains integer *n* (3<=β€<=*n*<=β€<=100) β amount of worm's forms. The second line contains *n* space-separated integers *a**i* (1<=β€<=*a**i*<=β€<=1000) β lengths of worms of each form. | Output 3 distinct integers *i* *j* *k* (1<=β€<=*i*,<=*j*,<=*k*<=β€<=*n*) β such indexes of worm's forms that *a**i*<==<=*a**j*<=+<=*a**k*. If there is no such triple, output -1. If there are several solutions, output any of them. It possible that *a**j*<==<=*a**k*. | [
"5\n1 2 3 5 7\n",
"5\n1 8 1 5 1\n"
] | [
"3 2 1\n",
"-1\n"
] | none | [
{
"input": "5\n1 2 3 5 7",
"output": "3 2 1"
},
{
"input": "5\n1 8 1 5 1",
"output": "-1"
},
{
"input": "4\n303 872 764 401",
"output": "-1"
},
{
"input": "6\n86 402 133 524 405 610",
"output": "6 4 1"
},
{
"input": "8\n217 779 418 895 996 473 3 22",
"output":... | 62 | 0 | 0 | 706 |
357 | Group of Students | [
"brute force",
"greedy",
"implementation"
] | null | null | At the beginning of the school year Berland State University starts two city school programming groups, for beginners and for intermediate coders. The children were tested in order to sort them into groups. According to the results, each student got some score from 1 to *m* points. We know that *c*1 schoolchildren got ... | The first line contains integer *m* (2<=β€<=*m*<=β€<=100). The second line contains *m* integers *c*1, *c*2, ..., *c**m*, separated by single spaces (0<=β€<=*c**i*<=β€<=100). The third line contains two space-separated integers *x* and *y* (1<=β€<=*x*<=β€<=*y*<=β€<=10000). At least one *c**i* is greater than 0. | If it is impossible to pick a passing rate in a way that makes the size of each resulting groups at least *x* and at most *y*, print 0. Otherwise, print an integer from 1 to *m* β the passing rate you'd like to suggest. If there are multiple possible answers, print any of them. | [
"5\n3 4 3 2 1\n6 8\n",
"5\n0 3 3 4 2\n3 10\n",
"2\n2 5\n3 6\n"
] | [
"3\n",
"4\n",
"0\n"
] | In the first sample the beginner group has 7 students, the intermediate group has 6 of them.
In the second sample another correct answer is 3. | [
{
"input": "5\n3 4 3 2 1\n6 8",
"output": "3"
},
{
"input": "5\n0 3 3 4 2\n3 10",
"output": "4"
},
{
"input": "2\n2 5\n3 6",
"output": "0"
},
{
"input": "3\n0 1 0\n2 10",
"output": "0"
},
{
"input": "5\n2 2 2 2 2\n5 5",
"output": "0"
},
{
"input": "10\... | 108 | 0 | 0 | 707 | |
733 | Grasshopper And the String | [
"implementation"
] | null | null | One day, the Grasshopper was jumping on the lawn and found a piece of paper with a string. Grasshopper became interested what is the minimum jump ability he should have in order to be able to reach the far end of the string, jumping only on vowels of the English alphabet. Jump ability is the maximum possible length of ... | The first line contains non-empty string consisting of capital English letters. It is guaranteed that the length of the string does not exceed 100. | Print single integer *a*Β β the minimum jump ability of the Grasshopper (in the number of symbols) that is needed to overcome the given string, jumping only on vowels. | [
"ABABBBACFEYUKOTT\n",
"AAA\n"
] | [
"4",
"1"
] | none | [
{
"input": "ABABBBACFEYUKOTT",
"output": "4"
},
{
"input": "AAA",
"output": "1"
},
{
"input": "A",
"output": "1"
},
{
"input": "B",
"output": "2"
},
{
"input": "AEYUIOAEIYAEOUIYOEIUYEAOIUEOEAYOEIUYAEOUIYEOIKLMJNHGTRWSDZXCVBNMHGFDSXVWRTPPPLKMNBXIUOIUOIUOIUOOIU",
... | 109 | 20,172,800 | 3 | 708 | |
913 | Christmas Spruce | [
"implementation",
"trees"
] | null | null | Consider a rooted tree. A rooted tree has one special vertex called the root. All edges are directed from the root. Vertex *u* is called a child of vertex *v* and vertex *v* is called a parent of vertex *u* if there exists a directed edge from *v* to *u*. A vertex is called a leaf if it doesn't have children and has a ... | The first line contains one integer *n*Β β the number of vertices in the tree (3<=β€<=*n*<=β€<=1<=000). Each of the next *n*<=-<=1 lines contains one integer *p**i* (1<=β€<=*i*<=β€<=*n*<=-<=1)Β β the index of the parent of the *i*<=+<=1-th vertex (1<=β€<=*p**i*<=β€<=*i*).
Vertex 1 is the root. It's guaranteed that the root ha... | Print "Yes" if the tree is a spruce and "No" otherwise. | [
"4\n1\n1\n1\n",
"7\n1\n1\n1\n2\n2\n2\n",
"8\n1\n1\n1\n1\n3\n3\n3\n"
] | [
"Yes\n",
"No\n",
"Yes\n"
] | The first example:
<img class="tex-graphics" src="https://espresso.codeforces.com/8dd976913226df83d535dfa66193f5525f8471bc.png" style="max-width: 100.0%;max-height: 100.0%;"/>
The second example:
<img class="tex-graphics" src="https://espresso.codeforces.com/44dad5804f5290a2e026c9c41a15151562df8682.png" style="max-w... | [
{
"input": "4\n1\n1\n1",
"output": "Yes"
},
{
"input": "7\n1\n1\n1\n2\n2\n2",
"output": "No"
},
{
"input": "8\n1\n1\n1\n1\n3\n3\n3",
"output": "Yes"
},
{
"input": "3\n1\n1",
"output": "No"
},
{
"input": "13\n1\n2\n2\n2\n1\n6\n6\n6\n1\n10\n10\n10",
"output": "N... | 93 | 307,200 | 0 | 709 | |
609 | USB Flash Drives | [
"greedy",
"implementation",
"sortings"
] | null | null | Sean is trying to save a large file to a USB flash drive. He has *n* USB flash drives with capacities equal to *a*1,<=*a*2,<=...,<=*a**n* megabytes. The file size is equal to *m* megabytes.
Find the minimum number of USB flash drives needed to write Sean's file, if he can split the file between drives. | The first line contains positive integer *n* (1<=β€<=*n*<=β€<=100) β the number of USB flash drives.
The second line contains positive integer *m* (1<=β€<=*m*<=β€<=105) β the size of Sean's file.
Each of the next *n* lines contains positive integer *a**i* (1<=β€<=*a**i*<=β€<=1000) β the sizes of USB flash drives in megabyt... | Print the minimum number of USB flash drives to write Sean's file, if he can split the file between drives. | [
"3\n5\n2\n1\n3\n",
"3\n6\n2\n3\n2\n",
"2\n5\n5\n10\n"
] | [
"2\n",
"3\n",
"1\n"
] | In the first example Sean needs only two USB flash drives β the first and the third.
In the second example Sean needs all three USB flash drives.
In the third example Sean needs only one USB flash drive and he can use any available USB flash drive β the first or the second. | [
{
"input": "3\n5\n2\n1\n3",
"output": "2"
},
{
"input": "3\n6\n2\n3\n2",
"output": "3"
},
{
"input": "2\n5\n5\n10",
"output": "1"
},
{
"input": "5\n16\n8\n1\n3\n4\n9",
"output": "2"
},
{
"input": "10\n121\n10\n37\n74\n56\n42\n39\n6\n68\n8\n100",
"output": "2"
... | 109 | 0 | 0 | 710 |
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