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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
816 | Karen and Morning | [
"brute force",
"implementation"
] | null | null | Karen is getting ready for a new school day!
It is currently hh:mm, given in a 24-hour format. As you know, Karen loves palindromes, and she believes that it is good luck to wake up when the time is a palindrome.
What is the minimum number of minutes she should sleep, such that, when she wakes up, the time is a palindrome?
Remember that a palindrome is a string that reads the same forwards and backwards. For instance, 05:39 is not a palindrome, because 05:39 backwards is 93:50. On the other hand, 05:50 is a palindrome, because 05:50 backwards is 05:50. | The first and only line of input contains a single string in the format hh:mm (00<=β€<= hh <=β€<=23, 00<=β€<= mm <=β€<=59). | Output a single integer on a line by itself, the minimum number of minutes she should sleep, such that, when she wakes up, the time is a palindrome. | [
"05:39\n",
"13:31\n",
"23:59\n"
] | [
"11\n",
"0\n",
"1\n"
] | In the first test case, the minimum number of minutes Karen should sleep for is 11. She can wake up at 05:50, when the time is a palindrome.
In the second test case, Karen can wake up immediately, as the current time, 13:31, is already a palindrome.
In the third test case, the minimum number of minutes Karen should sleep for is 1 minute. She can wake up at 00:00, when the time is a palindrome. | [
{
"input": "05:39",
"output": "11"
},
{
"input": "13:31",
"output": "0"
},
{
"input": "23:59",
"output": "1"
},
{
"input": "13:32",
"output": "69"
},
{
"input": "14:40",
"output": "1"
},
{
"input": "14:00",
"output": "41"
},
{
"input": "05:... | 77 | 6,758,400 | 0 | 919 | |
266 | Stones on the Table | [
"implementation"
] | null | null | There are *n* stones on the table in a row, each of them can be red, green or blue. Count the minimum number of stones to take from the table so that any two neighboring stones had different colors. Stones in a row are considered neighboring if there are no other stones between them. | The first line contains integer *n* (1<=β€<=*n*<=β€<=50) β the number of stones on the table.
The next line contains string *s*, which represents the colors of the stones. We'll consider the stones in the row numbered from 1 to *n* from left to right. Then the *i*-th character *s* equals "R", if the *i*-th stone is red, "G", if it's green and "B", if it's blue. | Print a single integer β the answer to the problem. | [
"3\nRRG\n",
"5\nRRRRR\n",
"4\nBRBG\n"
] | [
"1\n",
"4\n",
"0\n"
] | none | [
{
"input": "3\nRRG",
"output": "1"
},
{
"input": "5\nRRRRR",
"output": "4"
},
{
"input": "4\nBRBG",
"output": "0"
},
{
"input": "1\nB",
"output": "0"
},
{
"input": "2\nBG",
"output": "0"
},
{
"input": "3\nBGB",
"output": "0"
},
{
"input": "... | 30 | 0 | 0 | 920 | |
884 | Bertown Subway | [
"dfs and similar",
"greedy",
"math"
] | null | null | The construction of subway in Bertown is almost finished! The President of Berland will visit this city soon to look at the new subway himself.
There are *n* stations in the subway. It was built according to the Bertown Transport Law:
1. For each station *i* there exists exactly one train that goes from this station. Its destination station is *p**i*, possibly *p**i*<==<=*i*; 1. For each station *i* there exists exactly one station *j* such that *p**j*<==<=*i*.
The President will consider the convenience of subway after visiting it. The convenience is the number of ordered pairs (*x*,<=*y*) such that person can start at station *x* and, after taking some subway trains (possibly zero), arrive at station *y* (1<=β€<=*x*,<=*y*<=β€<=*n*).
The mayor of Bertown thinks that if the subway is not convenient enough, then the President might consider installing a new mayor (and, of course, the current mayor doesn't want it to happen). Before President visits the city mayor has enough time to rebuild some paths of subway, thus changing the values of *p**i* for not more than two subway stations. Of course, breaking the Bertown Transport Law is really bad, so the subway must be built according to the Law even after changes.
The mayor wants to do these changes in such a way that the convenience of the subway is maximized. Help him to calculate the maximum possible convenience he can get! | The first line contains one integer number *n* (1<=β€<=*n*<=β€<=100000) β the number of stations.
The second line contains *n* integer numbers *p*1, *p*2, ..., *p**n* (1<=β€<=*p**i*<=β€<=*n*) β the current structure of the subway. All these numbers are distinct. | Print one number β the maximum possible value of convenience. | [
"3\n2 1 3\n",
"5\n1 5 4 3 2\n"
] | [
"9\n",
"17\n"
] | In the first example the mayor can change *p*<sub class="lower-index">2</sub> to 3 and *p*<sub class="lower-index">3</sub> to 1, so there will be 9 pairs: (1,β1), (1,β2), (1,β3), (2,β1), (2,β2), (2,β3), (3,β1), (3,β2), (3,β3).
In the second example the mayor can change *p*<sub class="lower-index">2</sub> to 4 and *p*<sub class="lower-index">3</sub> to 5. | [
{
"input": "3\n2 1 3",
"output": "9"
},
{
"input": "5\n1 5 4 3 2",
"output": "17"
},
{
"input": "1\n1",
"output": "1"
},
{
"input": "2\n1 2",
"output": "4"
},
{
"input": "2\n2 1",
"output": "4"
},
{
"input": "100\n98 52 63 2 18 96 31 58 84 40 41 45 66 ... | 327 | 13,312,000 | 3 | 921 | |
897 | Chtholly's request | [
"brute force"
] | null | null | β I experienced so many great things.
β You gave me memories like dreams... But I have to leave now...
β One last request, can you...
β Help me solve a Codeforces problem?
β ......
β What?
Chtholly has been thinking about a problem for days:
If a number is palindrome and length of its decimal representation without leading zeros is even, we call it a zcy number. A number is palindrome means when written in decimal representation, it contains no leading zeros and reads the same forwards and backwards. For example 12321 and 1221 are palindromes and 123 and 12451 are not. Moreover, 1221 is zcy number and 12321 is not.
Given integers *k* and *p*, calculate the sum of the *k* smallest zcy numbers and output this sum modulo *p*.
Unfortunately, Willem isn't good at solving this kind of problems, so he asks you for help! | The first line contains two integers *k* and *p* (1<=β€<=*k*<=β€<=105,<=1<=β€<=*p*<=β€<=109). | Output single integerΒ β answer to the problem. | [
"2 100\n",
"5 30\n"
] | [
"33\n",
"15\n"
] | In the first example, the smallest zcy number is 11, and the second smallest zcy number is 22.
In the second example, <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/68fffad54395f7d920ad0384e07c6215ddc64141.png" style="max-width: 100.0%;max-height: 100.0%;"/>. | [
{
"input": "2 100",
"output": "33"
},
{
"input": "5 30",
"output": "15"
},
{
"input": "42147 412393322",
"output": "251637727"
},
{
"input": "77809 868097296",
"output": "440411873"
},
{
"input": "5105 443422097",
"output": "363192634"
},
{
"input": "7... | 2,000 | 0 | 0 | 922 | |
474 | Keyboard | [
"implementation"
] | null | null | Our good friend Mole is trying to code a big message. He is typing on an unusual keyboard with characters arranged in following way:
Unfortunately Mole is blind, so sometimes it is problem for him to put his hands accurately. He accidentally moved both his hands with one position to the left or to the right. That means that now he presses not a button he wants, but one neighboring button (left or right, as specified in input).
We have a sequence of characters he has typed and we want to find the original message. | First line of the input contains one letter describing direction of shifting ('L' or 'R' respectively for left or right).
Second line contains a sequence of characters written by Mole. The size of this sequence will be no more than 100. Sequence contains only symbols that appear on Mole's keyboard. It doesn't contain spaces as there is no space on Mole's keyboard.
It is guaranteed that even though Mole hands are moved, he is still pressing buttons on keyboard and not hitting outside it. | Print a line that contains the original message. | [
"R\ns;;upimrrfod;pbr\n"
] | [
"allyouneedislove\n"
] | none | [
{
"input": "R\ns;;upimrrfod;pbr",
"output": "allyouneedislove"
},
{
"input": "R\nwertyuiop;lkjhgfdsxcvbnm,.",
"output": "qwertyuiolkjhgfdsazxcvbnm,"
},
{
"input": "L\nzxcvbnm,kjhgfdsaqwertyuio",
"output": "xcvbnm,.lkjhgfdswertyuiop"
},
{
"input": "R\nbubbuduppudup",
"outp... | 30 | 0 | 0 | 923 | |
557 | Ilya and Diplomas | [
"greedy",
"implementation",
"math"
] | null | null | Soon a school Olympiad in Informatics will be held in Berland, *n* schoolchildren will participate there.
At a meeting of the jury of the Olympiad it was decided that each of the *n* participants, depending on the results, will get a diploma of the first, second or third degree. Thus, each student will receive exactly one diploma.
They also decided that there must be given at least *min*1 and at most *max*1 diplomas of the first degree, at least *min*2 and at most *max*2 diplomas of the second degree, and at least *min*3 and at most *max*3 diplomas of the third degree.
After some discussion it was decided to choose from all the options of distributing diplomas satisfying these limitations the one that maximizes the number of participants who receive diplomas of the first degree. Of all these options they select the one which maximizes the number of the participants who receive diplomas of the second degree. If there are multiple of these options, they select the option that maximizes the number of diplomas of the third degree.
Choosing the best option of distributing certificates was entrusted to Ilya, one of the best programmers of Berland. However, he found more important things to do, so it is your task now to choose the best option of distributing of diplomas, based on the described limitations.
It is guaranteed that the described limitations are such that there is a way to choose such an option of distributing diplomas that all *n* participants of the Olympiad will receive a diploma of some degree. | The first line of the input contains a single integer *n* (3<=β€<=*n*<=β€<=3Β·106)Β βΒ the number of schoolchildren who will participate in the Olympiad.
The next line of the input contains two integers *min*1 and *max*1 (1<=β€<=*min*1<=β€<=*max*1<=β€<=106)Β βΒ the minimum and maximum limits on the number of diplomas of the first degree that can be distributed.
The third line of the input contains two integers *min*2 and *max*2 (1<=β€<=*min*2<=β€<=*max*2<=β€<=106)Β βΒ the minimum and maximum limits on the number of diplomas of the second degree that can be distributed.
The next line of the input contains two integers *min*3 and *max*3 (1<=β€<=*min*3<=β€<=*max*3<=β€<=106)Β βΒ the minimum and maximum limits on the number of diplomas of the third degree that can be distributed.
It is guaranteed that *min*1<=+<=*min*2<=+<=*min*3<=β€<=*n*<=β€<=*max*1<=+<=*max*2<=+<=*max*3. | In the first line of the output print three numbers, showing how many diplomas of the first, second and third degree will be given to students in the optimal variant of distributing diplomas.
The optimal variant of distributing diplomas is the one that maximizes the number of students who receive diplomas of the first degree. Of all the suitable options, the best one is the one which maximizes the number of participants who receive diplomas of the second degree. If there are several of these options, the best one is the one that maximizes the number of diplomas of the third degree. | [
"6\n1 5\n2 6\n3 7\n",
"10\n1 2\n1 3\n1 5\n",
"6\n1 3\n2 2\n2 2\n"
] | [
"1 2 3 \n",
"2 3 5 \n",
"2 2 2 \n"
] | none | [
{
"input": "6\n1 5\n2 6\n3 7",
"output": "1 2 3 "
},
{
"input": "10\n1 2\n1 3\n1 5",
"output": "2 3 5 "
},
{
"input": "6\n1 3\n2 2\n2 2",
"output": "2 2 2 "
},
{
"input": "55\n1 1000000\n40 50\n10 200",
"output": "5 40 10 "
},
{
"input": "3\n1 1\n1 1\n1 1",
"o... | 62 | 0 | 3 | 925 | |
755 | PolandBall and Game | [
"binary search",
"data structures",
"games",
"greedy",
"sortings",
"strings"
] | null | null | PolandBall is playing a game with EnemyBall. The rules are simple. Players have to say words in turns. You cannot say a word which was already said. PolandBall starts. The Ball which can't say a new word loses.
You're given two lists of words familiar to PolandBall and EnemyBall. Can you determine who wins the game, if both play optimally? | The first input line contains two integers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=103)Β β number of words PolandBall and EnemyBall know, respectively.
Then *n* strings follow, one per lineΒ β words familiar to PolandBall.
Then *m* strings follow, one per lineΒ β words familiar to EnemyBall.
Note that one Ball cannot know a word more than once (strings are unique), but some words can be known by both players.
Each word is non-empty and consists of no more than 500 lowercase English alphabet letters. | In a single line of print the answerΒ β "YES" if PolandBall wins and "NO" otherwise. Both Balls play optimally. | [
"5 1\npolandball\nis\na\ncool\ncharacter\nnope\n",
"2 2\nkremowka\nwadowicka\nkremowka\nwiedenska\n",
"1 2\na\na\nb\n"
] | [
"YES",
"YES",
"NO"
] | In the first example PolandBall knows much more words and wins effortlessly.
In the second example if PolandBall says kremowka first, then EnemyBall cannot use that word anymore. EnemyBall can only say wiedenska. PolandBall says wadowicka and wins. | [
{
"input": "5 1\npolandball\nis\na\ncool\ncharacter\nnope",
"output": "YES"
},
{
"input": "2 2\nkremowka\nwadowicka\nkremowka\nwiedenska",
"output": "YES"
},
{
"input": "1 2\na\na\nb",
"output": "NO"
},
{
"input": "2 2\na\nb\nb\nc",
"output": "YES"
},
{
"input": "... | 93 | 307,200 | 0 | 926 | |
631 | Interview | [
"brute force",
"implementation"
] | null | null | Blake is a CEO of a large company called "Blake Technologies". He loves his company very much and he thinks that his company should be the best. That is why every candidate needs to pass through the interview that consists of the following problem.
We define function *f*(*x*,<=*l*,<=*r*) as a bitwise OR of integers *x**l*,<=*x**l*<=+<=1,<=...,<=*x**r*, where *x**i* is the *i*-th element of the array *x*. You are given two arrays *a* and *b* of length *n*. You need to determine the maximum value of sum *f*(*a*,<=*l*,<=*r*)<=+<=*f*(*b*,<=*l*,<=*r*) among all possible 1<=β€<=*l*<=β€<=*r*<=β€<=*n*. | The first line of the input contains a single integer *n* (1<=β€<=*n*<=β€<=1000)Β β the length of the arrays.
The second line contains *n* integers *a**i* (0<=β€<=*a**i*<=β€<=109).
The third line contains *n* integers *b**i* (0<=β€<=*b**i*<=β€<=109). | Print a single integerΒ β the maximum value of sum *f*(*a*,<=*l*,<=*r*)<=+<=*f*(*b*,<=*l*,<=*r*) among all possible 1<=β€<=*l*<=β€<=*r*<=β€<=*n*. | [
"5\n1 2 4 3 2\n2 3 3 12 1\n",
"10\n13 2 7 11 8 4 9 8 5 1\n5 7 18 9 2 3 0 11 8 6\n"
] | [
"22",
"46"
] | Bitwise OR of two non-negative integers *a* and *b* is the number *c*β=β*a* *OR* *b*, such that each of its digits in binary notation is 1 if and only if at least one of *a* or *b* have 1 in the corresponding position in binary notation.
In the first sample, one of the optimal answers is *l*β=β2 and *r*β=β4, because *f*(*a*,β2,β4)β+β*f*(*b*,β2,β4)β=β(2 *OR* 4 *OR* 3)β+β(3 *OR* 3 *OR* 12)β=β7β+β15β=β22. Other ways to get maximum value is to choose *l*β=β1 and *r*β=β4, *l*β=β1 and *r*β=β5, *l*β=β2 and *r*β=β4, *l*β=β2 and *r*β=β5, *l*β=β3 and *r*β=β4, or *l*β=β3 and *r*β=β5.
In the second sample, the maximum value is obtained for *l*β=β1 and *r*β=β9. | [
{
"input": "5\n1 2 4 3 2\n2 3 3 12 1",
"output": "22"
},
{
"input": "10\n13 2 7 11 8 4 9 8 5 1\n5 7 18 9 2 3 0 11 8 6",
"output": "46"
},
{
"input": "25\n12 30 38 109 81 124 80 33 38 48 29 78 96 48 96 27 80 77 102 65 80 113 31 118 35\n25 64 95 13 12 6 111 80 85 16 61 119 23 65 73 65 20 9... | 0 | 0 | -1 | 927 | |
669 | Little Artem and Presents | [
"math"
] | null | null | Little Artem got *n* stones on his birthday and now wants to give some of them to Masha. He knows that Masha cares more about the fact of receiving the present, rather than the value of that present, so he wants to give her stones as many times as possible. However, Masha remembers the last present she received, so Artem can't give her the same number of stones twice in a row. For example, he can give her 3 stones, then 1 stone, then again 3 stones, but he can't give her 3 stones and then again 3 stones right after that.
How many times can Artem give presents to Masha? | The only line of the input contains a single integer *n* (1<=β€<=*n*<=β€<=109)Β β number of stones Artem received on his birthday. | Print the maximum possible number of times Artem can give presents to Masha. | [
"1\n",
"2\n",
"3\n",
"4\n"
] | [
"1\n",
"1\n",
"2\n",
"3\n"
] | In the first sample, Artem can only give 1 stone to Masha.
In the second sample, Atrem can give Masha 1 or 2 stones, though he can't give her 1 stone two times.
In the third sample, Atrem can first give Masha 2 stones, a then 1 more stone.
In the fourth sample, Atrem can first give Masha 1 stone, then 2 stones, and finally 1 stone again. | [
{
"input": "1",
"output": "1"
},
{
"input": "2",
"output": "1"
},
{
"input": "3",
"output": "2"
},
{
"input": "4",
"output": "3"
},
{
"input": "100",
"output": "67"
},
{
"input": "101",
"output": "67"
},
{
"input": "102",
"output": "68"... | 77 | 6,758,400 | 3 | 929 | |
11 | Forward, march! | [
"binary search",
"dp",
"greedy"
] | E. Forward, march! | 1 | 64 | Jack has become a soldier now. Unfortunately, he has trouble with the drill. Instead of marching beginning with the left foot and then changing legs with each step, as ordered, he keeps repeating a sequence of steps, in which he sometimes makes the wrong steps or β horror of horrors! β stops for a while. For example, if Jack uses the sequence 'right, left, break', when the sergeant yells: 'Left! Right! Left! Right! Left! Right!', Jack first makes a step with the right foot, then one with the left foot, then he is confused and stops for a moment, then again - this time according to the order - starts with the right foot, then uses the left foot, then - to the sergeant's irritation - he stops to catch his breath, to incorrectly start with the right foot again... Marching this way, Jack will make the step that he is supposed to in the given moment in only one third of cases.
When the officers convinced him he should do something about it, Jack decided to modify the basic sequence of steps that he repeats. However, in order not to get too tired, he has decided that the only thing he'll do is adding any number of breaks in any positions of the original sequence (a break corresponds to stopping for the duration of one step). Of course, Jack can't make a step on the same foot twice in a row, if there is no pause between these steps. It is, however, not impossible that the sequence of steps he used so far is incorrect (it would explain a lot, actually).
Help Private Jack! Given the sequence of steps he keeps repeating, calculate the maximal percentage of time that he can spend marching correctly after adding some breaks to his scheme. | The first line of input contains a sequence consisting only of characters 'L', 'R' and 'X', where 'L' corresponds to a step with the left foot, 'R' β with the right foot, and 'X' β to a break. The length of the sequence will not exceed 106. | Output the maximum percentage of time that Jack can spend marching correctly, rounded down to exactly six digits after the decimal point. | [
"X\n",
"LXRR\n"
] | [
"0.000000\n",
"50.000000\n"
] | In the second example, if we add two breaks to receive LXXRXR, Jack will march: LXXRXRLXXRXRL... instead of LRLRLRLRLRLRL... and will make the correct step in half the cases. If we didn't add any breaks, the sequence would be incorrect β Jack can't step on his right foot twice in a row. | [
{
"input": "X",
"output": "0.000000"
},
{
"input": "LXRR",
"output": "50.000000"
},
{
"input": "LXRR",
"output": "50.000000"
},
{
"input": "LLXRXLXRLR",
"output": "50.000000"
},
{
"input": "RXRRXXXRXXRR",
"output": "37.500000"
},
{
"input": "LLLRLXRXLL... | 60 | 0 | 0 | 930 |
255 | Greg's Workout | [
"implementation"
] | null | null | Greg is a beginner bodybuilder. Today the gym coach gave him the training plan. All it had was *n* integers *a*1,<=*a*2,<=...,<=*a**n*. These numbers mean that Greg needs to do exactly *n* exercises today. Besides, Greg should repeat the *i*-th in order exercise *a**i* times.
Greg now only does three types of exercises: "chest" exercises, "biceps" exercises and "back" exercises. Besides, his training is cyclic, that is, the first exercise he does is a "chest" one, the second one is "biceps", the third one is "back", the fourth one is "chest", the fifth one is "biceps", and so on to the *n*-th exercise.
Now Greg wonders, which muscle will get the most exercise during his training. We know that the exercise Greg repeats the maximum number of times, trains the corresponding muscle the most. Help Greg, determine which muscle will get the most training. | The first line contains integer *n* (1<=β€<=*n*<=β€<=20). The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=25) β the number of times Greg repeats the exercises. | Print word "chest" (without the quotes), if the chest gets the most exercise, "biceps" (without the quotes), if the biceps gets the most exercise and print "back" (without the quotes) if the back gets the most exercise.
It is guaranteed that the input is such that the answer to the problem is unambiguous. | [
"2\n2 8\n",
"3\n5 1 10\n",
"7\n3 3 2 7 9 6 8\n"
] | [
"biceps\n",
"back\n",
"chest\n"
] | In the first sample Greg does 2 chest, 8 biceps and zero back exercises, so the biceps gets the most exercises.
In the second sample Greg does 5 chest, 1 biceps and 10 back exercises, so the back gets the most exercises.
In the third sample Greg does 18 chest, 12 biceps and 8 back exercises, so the chest gets the most exercise. | [
{
"input": "2\n2 8",
"output": "biceps"
},
{
"input": "3\n5 1 10",
"output": "back"
},
{
"input": "7\n3 3 2 7 9 6 8",
"output": "chest"
},
{
"input": "4\n5 6 6 2",
"output": "chest"
},
{
"input": "5\n8 2 2 6 3",
"output": "chest"
},
{
"input": "6\n8 7 ... | 30 | 0 | -1 | 931 | |
14 | Letter | [
"implementation"
] | A. Letter | 1 | 64 | A boy Bob likes to draw. Not long ago he bought a rectangular graph (checked) sheet with *n* rows and *m* columns. Bob shaded some of the squares on the sheet. Having seen his masterpiece, he decided to share it with his elder brother, who lives in Flatland. Now Bob has to send his picture by post, but because of the world economic crisis and high oil prices, he wants to send his creation, but to spend as little money as possible. For each sent square of paper (no matter whether it is shaded or not) Bob has to pay 3.14 burles. Please, help Bob cut out of his masterpiece a rectangle of the minimum cost, that will contain all the shaded squares. The rectangle's sides should be parallel to the sheet's sides. | The first line of the input data contains numbers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=50), *n* β amount of lines, and *m* β amount of columns on Bob's sheet. The following *n* lines contain *m* characters each. Character Β«.Β» stands for a non-shaded square on the sheet, and Β«*Β» β for a shaded square. It is guaranteed that Bob has shaded at least one square. | Output the required rectangle of the minimum cost. Study the output data in the sample tests to understand the output format better. | [
"6 7\n.......\n..***..\n..*....\n..***..\n..*....\n..***..\n",
"3 3\n***\n*.*\n***\n"
] | [
"***\n*..\n***\n*..\n***\n",
"***\n*.*\n***\n"
] | none | [
{
"input": "6 7\n.......\n..***..\n..*....\n..***..\n..*....\n..***..",
"output": "***\n*..\n***\n*..\n***"
},
{
"input": "3 3\n***\n*.*\n***",
"output": "***\n*.*\n***"
},
{
"input": "1 1\n*",
"output": "*"
},
{
"input": "2 1\n*\n*",
"output": "*\n*"
},
{
"input"... | 218 | 307,200 | 3.888711 | 935 |
205 | Little Elephant and Sorting | [
"brute force",
"greedy"
] | null | null | The Little Elephant loves sortings.
He has an array *a* consisting of *n* integers. Let's number the array elements from 1 to *n*, then the *i*-th element will be denoted as *a**i*. The Little Elephant can make one move to choose an arbitrary pair of integers *l* and *r* (1<=β€<=*l*<=β€<=*r*<=β€<=*n*) and increase *a**i* by 1 for all *i* such that *l*<=β€<=*i*<=β€<=*r*.
Help the Little Elephant find the minimum number of moves he needs to convert array *a* to an arbitrary array sorted in the non-decreasing order. Array *a*, consisting of *n* elements, is sorted in the non-decreasing order if for any *i* (1<=β€<=*i*<=<<=*n*) *a**i*<=β€<=*a**i*<=+<=1 holds. | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=105) β the size of array *a*. The next line contains *n* integers, separated by single spaces β array *a* (1<=β€<=*a**i*<=β€<=109). The array elements are listed in the line in the order of their index's increasing. | In a single line print a single integer β the answer to the problem.
Please, do not use the %lld specifier to read or write 64-bit integers in Π‘++. It is preferred to use the cin, cout streams or the %I64d specifier. | [
"3\n1 2 3\n",
"3\n3 2 1\n",
"4\n7 4 1 47\n"
] | [
"0\n",
"2\n",
"6\n"
] | In the first sample the array is already sorted in the non-decreasing order, so the answer is 0.
In the second sample you need to perform two operations: first increase numbers from second to third (after that the array will be: [3, 3, 2]), and second increase only the last element (the array will be: [3, 3, 3]).
In the third sample you should make at least 6 steps. The possible sequence of the operations is: (2; 3), (2; 3), (2; 3), (3; 3), (3; 3), (3; 3). After that the array converts to [7, 7, 7, 47]. | [
{
"input": "3\n1 2 3",
"output": "0"
},
{
"input": "3\n3 2 1",
"output": "2"
},
{
"input": "4\n7 4 1 47",
"output": "6"
},
{
"input": "10\n1 2 3 4 5 6 7 8 9 1000000000",
"output": "0"
},
{
"input": "10\n1000000000 1 1000000000 1 1000000000 1 1000000000 1 100000000... | 46 | 6,963,200 | 0 | 936 | |
212 | IT Restaurants | [
"dfs and similar",
"dp",
"trees"
] | null | null | Π‘ity N. has a huge problem with roads, food and IT-infrastructure. In total the city has *n* junctions, some pairs of them are connected by bidirectional roads. The road network consists of *n*<=-<=1 roads, you can get from any junction to any other one by these roads. Yes, you're right β the road network forms an undirected tree.
Recently, the Mayor came up with a way that eliminates the problems with the food and the IT-infrastructure at the same time! He decided to put at the city junctions restaurants of two well-known cafe networks for IT professionals: "iMac D0naldz" and "Burger Bing". Since the network owners are not friends, it is strictly prohibited to place two restaurants of different networks on neighboring junctions. There are other requirements. Here's the full list:
- each junction must have at most one restaurant; - each restaurant belongs either to "iMac D0naldz", or to "Burger Bing"; - each network should build at least one restaurant; - there is no pair of junctions that are connected by a road and contains restaurants of different networks.
The Mayor is going to take a large tax from each restaurant, so he is interested in making the total number of the restaurants as large as possible.
Help the Mayor to analyze the situation. Find all such pairs of (*a*,<=*b*) that *a* restaurants can belong to "iMac D0naldz", *b* restaurants can belong to "Burger Bing", and the sum of *a*<=+<=*b* is as large as possible. | The first input line contains integer *n* (3<=β€<=*n*<=β€<=5000) β the number of junctions in the city. Next *n*<=-<=1 lines list all roads one per line. Each road is given as a pair of integers *x**i*,<=*y**i* (1<=β€<=*x**i*,<=*y**i*<=β€<=*n*) β the indexes of connected junctions. Consider the junctions indexed from 1 to *n*.
It is guaranteed that the given road network is represented by an undirected tree with *n* vertexes. | Print on the first line integer *z* β the number of sought pairs. Then print all sought pairs (*a*,<=*b*) in the order of increasing of the first component *a*. | [
"5\n1 2\n2 3\n3 4\n4 5\n",
"10\n1 2\n2 3\n3 4\n5 6\n6 7\n7 4\n8 9\n9 10\n10 4\n"
] | [
"3\n1 3\n2 2\n3 1\n",
"6\n1 8\n2 7\n3 6\n6 3\n7 2\n8 1\n"
] | The figure below shows the answers to the first test case. The junctions with "iMac D0naldz" restaurants are marked red and "Burger Bing" restaurants are marked blue.
<img class="tex-graphics" src="https://espresso.codeforces.com/acf0a2618a71a09921a44d636776197510b78cd4.png" style="max-width: 100.0%;max-height: 100.0%;"/> | [
{
"input": "5\n1 2\n2 3\n3 4\n4 5",
"output": "3\n1 3\n2 2\n3 1"
},
{
"input": "10\n1 2\n2 3\n3 4\n5 6\n6 7\n7 4\n8 9\n9 10\n10 4",
"output": "6\n1 8\n2 7\n3 6\n6 3\n7 2\n8 1"
},
{
"input": "3\n3 1\n2 1",
"output": "1\n1 1"
},
{
"input": "4\n4 3\n4 1\n4 2",
"output": "2\n... | 92 | 0 | 0 | 941 | |
987 | Three displays | [
"brute force",
"dp",
"implementation"
] | null | null | It is the middle of 2018 and Maria Stepanovna, who lives outside Krasnokamensk (a town in Zabaikalsky region), wants to rent three displays to highlight an important problem.
There are $n$ displays placed along a road, and the $i$-th of them can display a text with font size $s_i$ only. Maria Stepanovna wants to rent such three displays with indices $i < j < k$ that the font size increases if you move along the road in a particular direction. Namely, the condition $s_i < s_j < s_k$ should be held.
The rent cost is for the $i$-th display is $c_i$. Please determine the smallest cost Maria Stepanovna should pay. | The first line contains a single integer $n$ ($3 \le n \le 3\,000$)Β β the number of displays.
The second line contains $n$ integers $s_1, s_2, \ldots, s_n$ ($1 \le s_i \le 10^9$)Β β the font sizes on the displays in the order they stand along the road.
The third line contains $n$ integers $c_1, c_2, \ldots, c_n$ ($1 \le c_i \le 10^8$)Β β the rent costs for each display. | If there are no three displays that satisfy the criteria, print -1. Otherwise print a single integerΒ β the minimum total rent cost of three displays with indices $i < j < k$ such that $s_i < s_j < s_k$. | [
"5\n2 4 5 4 10\n40 30 20 10 40\n",
"3\n100 101 100\n2 4 5\n",
"10\n1 2 3 4 5 6 7 8 9 10\n10 13 11 14 15 12 13 13 18 13\n"
] | [
"90\n",
"-1\n",
"33\n"
] | In the first example you can, for example, choose displays $1$, $4$ and $5$, because $s_1 < s_4 < s_5$ ($2 < 4 < 10$), and the rent cost is $40 + 10 + 40 = 90$.
In the second example you can't select a valid triple of indices, so the answer is -1. | [
{
"input": "5\n2 4 5 4 10\n40 30 20 10 40",
"output": "90"
},
{
"input": "3\n100 101 100\n2 4 5",
"output": "-1"
},
{
"input": "10\n1 2 3 4 5 6 7 8 9 10\n10 13 11 14 15 12 13 13 18 13",
"output": "33"
},
{
"input": "3\n1 2 3\n100000000 100000000 100000000",
"output": "300... | 155 | 2,969,600 | 3 | 943 | |
898 | Rounding | [
"implementation",
"math"
] | null | null | Vasya has a non-negative integer *n*. He wants to round it to nearest integer, which ends up with 0. If *n* already ends up with 0, Vasya considers it already rounded.
For example, if *n*<==<=4722 answer is 4720. If *n*<==<=5 Vasya can round it to 0 or to 10. Both ways are correct.
For given *n* find out to which integer will Vasya round it. | The first line contains single integer *n* (0<=β€<=*n*<=β€<=109)Β β number that Vasya has. | Print result of rounding *n*. Pay attention that in some cases answer isn't unique. In that case print any correct answer. | [
"5\n",
"113\n",
"1000000000\n",
"5432359\n"
] | [
"0\n",
"110\n",
"1000000000\n",
"5432360\n"
] | In the first example *n*β=β5. Nearest integers, that ends up with zero are 0 and 10. Any of these answers is correct, so you can print 0 or 10. | [
{
"input": "5",
"output": "0"
},
{
"input": "113",
"output": "110"
},
{
"input": "1000000000",
"output": "1000000000"
},
{
"input": "5432359",
"output": "5432360"
},
{
"input": "999999994",
"output": "999999990"
},
{
"input": "10",
"output": "10"
... | 77 | 7,065,600 | 3 | 944 | |
173 | Rock-Paper-Scissors | [
"implementation",
"math"
] | null | null | Nikephoros and Polycarpus play rock-paper-scissors. The loser gets pinched (not too severely!).
Let us remind you the rules of this game. Rock-paper-scissors is played by two players. In each round the players choose one of three items independently from each other. They show the items with their hands: a rock, scissors or paper. The winner is determined by the following rules: the rock beats the scissors, the scissors beat the paper and the paper beats the rock. If the players choose the same item, the round finishes with a draw.
Nikephoros and Polycarpus have played *n* rounds. In each round the winner gave the loser a friendly pinch and the loser ended up with a fresh and new red spot on his body. If the round finished in a draw, the players did nothing and just played on.
Nikephoros turned out to have worked out the following strategy: before the game began, he chose some sequence of items *A*<==<=(*a*1,<=*a*2,<=...,<=*a**m*), and then he cyclically showed the items from this sequence, starting from the first one. Cyclically means that Nikephoros shows signs in the following order: *a*1, *a*2, ..., *a**m*, *a*1, *a*2, ..., *a**m*, *a*1, ... and so on. Polycarpus had a similar strategy, only he had his own sequence of items *B*<==<=(*b*1,<=*b*2,<=...,<=*b**k*).
Determine the number of red spots on both players after they've played *n* rounds of the game. You can consider that when the game began, the boys had no red spots on them. | The first line contains integer *n* (1<=β€<=*n*<=β€<=2Β·109) β the number of the game's rounds.
The second line contains sequence *A* as a string of *m* characters and the third line contains sequence *B* as a string of *k* characters (1<=β€<=*m*,<=*k*<=β€<=1000). The given lines only contain characters "R", "S" and "P". Character "R" stands for the rock, character "S" represents the scissors and "P" represents the paper. | Print two space-separated integers: the numbers of red spots Nikephoros and Polycarpus have. | [
"7\nRPS\nRSPP\n",
"5\nRRRRRRRR\nR\n"
] | [
"3 2",
"0 0"
] | In the first sample the game went like this:
- R - R. Draw. - P - S. Nikephoros loses. - S - P. Polycarpus loses. - R - P. Nikephoros loses. - P - R. Polycarpus loses. - S - S. Draw. - R - P. Nikephoros loses.
Thus, in total Nikephoros has 3 losses (and 3 red spots), and Polycarpus only has 2. | [
{
"input": "7\nRPS\nRSPP",
"output": "3 2"
},
{
"input": "5\nRRRRRRRR\nR",
"output": "0 0"
},
{
"input": "23\nRSP\nRPSS",
"output": "7 8"
},
{
"input": "52\nRRPSS\nRSSPRPRPPP",
"output": "15 21"
},
{
"input": "1293\nRRPSSRSSPRPRPPPRPPPRPPPPPRPSPRSSRPSPPRPRR\nSSPSS... | 2,900 | 0 | 3 | 945 | |
832 | Sasha and Sticks | [
"games",
"math"
] | null | null | It's one more school day now. Sasha doesn't like classes and is always bored at them. So, each day he invents some game and plays in it alone or with friends.
Today he invented one simple game to play with Lena, with whom he shares a desk. The rules are simple. Sasha draws *n* sticks in a row. After that the players take turns crossing out exactly *k* sticks from left or right in each turn. Sasha moves first, because he is the inventor of the game. If there are less than *k* sticks on the paper before some turn, the game ends. Sasha wins if he makes strictly more moves than Lena. Sasha wants to know the result of the game before playing, you are to help him. | The first line contains two integers *n* and *k* (1<=β€<=*n*,<=*k*<=β€<=1018, *k*<=β€<=*n*)Β β the number of sticks drawn by Sasha and the number *k*Β β the number of sticks to be crossed out on each turn. | If Sasha wins, print "YES" (without quotes), otherwise print "NO" (without quotes).
You can print each letter in arbitrary case (upper of lower). | [
"1 1\n",
"10 4\n"
] | [
"YES\n",
"NO\n"
] | In the first example Sasha crosses out 1 stick, and then there are no sticks. So Lena can't make a move, and Sasha wins.
In the second example Sasha crosses out 4 sticks, then Lena crosses out 4 sticks, and after that there are only 2 sticks left. Sasha can't make a move. The players make equal number of moves, so Sasha doesn't win. | [
{
"input": "1 1",
"output": "YES"
},
{
"input": "10 4",
"output": "NO"
},
{
"input": "251656215122324104 164397544865601257",
"output": "YES"
},
{
"input": "963577813436662285 206326039287271924",
"output": "NO"
},
{
"input": "1000000000000000000 1",
"output":... | 0 | 0 | -1 | 947 | |
934 | A Compatible Pair | [
"brute force",
"games"
] | null | null | Nian is a monster which lives deep in the oceans. Once a year, it shows up on the land, devouring livestock and even people. In order to keep the monster away, people fill their villages with red colour, light, and cracking noise, all of which frighten the monster out of coming.
Little Tommy has *n* lanterns and Big Banban has *m* lanterns. Tommy's lanterns have brightness *a*1,<=*a*2,<=...,<=*a**n*, and Banban's have brightness *b*1,<=*b*2,<=...,<=*b**m* respectively.
Tommy intends to hide one of his lanterns, then Banban picks one of Tommy's non-hidden lanterns and one of his own lanterns to form a pair. The pair's brightness will be the product of the brightness of two lanterns.
Tommy wants to make the product as small as possible, while Banban tries to make it as large as possible.
You are asked to find the brightness of the chosen pair if both of them choose optimally. | The first line contains two space-separated integers *n* and *m* (2<=β€<=*n*,<=*m*<=β€<=50).
The second line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n*.
The third line contains *m* space-separated integers *b*1,<=*b*2,<=...,<=*b**m*.
All the integers range from <=-<=109 to 109. | Print a single integerΒ β the brightness of the chosen pair. | [
"2 2\n20 18\n2 14\n",
"5 3\n-1 0 1 2 3\n-1 0 1\n"
] | [
"252\n",
"2\n"
] | In the first example, Tommy will hide 20 and Banban will choose 18 from Tommy and 14 from himself.
In the second example, Tommy will hide 3 and Banban will choose 2 from Tommy and 1 from himself. | [
{
"input": "2 2\n20 18\n2 14",
"output": "252"
},
{
"input": "5 3\n-1 0 1 2 3\n-1 0 1",
"output": "2"
},
{
"input": "10 2\n1 6 2 10 2 3 2 10 6 4\n5 7",
"output": "70"
},
{
"input": "50 50\n1 6 2 10 2 3 2 10 6 4 5 0 3 1 7 3 2 4 4 2 1 5 0 6 10 1 8 0 10 9 0 4 10 5 5 7 4 9 9 5 5 ... | 61 | 4,505,600 | 0 | 948 | |
165 | Supercentral Point | [
"implementation"
] | null | null | One day Vasya painted a Cartesian coordinate system on a piece of paper and marked some set of points (*x*1,<=*y*1),<=(*x*2,<=*y*2),<=...,<=(*x**n*,<=*y**n*). Let's define neighbors for some fixed point from the given set (*x*,<=*y*):
- point (*x*',<=*y*') is (*x*,<=*y*)'s right neighbor, if *x*'<=><=*x* and *y*'<==<=*y* - point (*x*',<=*y*') is (*x*,<=*y*)'s left neighbor, if *x*'<=<<=*x* and *y*'<==<=*y* - point (*x*',<=*y*') is (*x*,<=*y*)'s lower neighbor, if *x*'<==<=*x* and *y*'<=<<=*y* - point (*x*',<=*y*') is (*x*,<=*y*)'s upper neighbor, if *x*'<==<=*x* and *y*'<=><=*y*
We'll consider point (*x*,<=*y*) from the given set supercentral, if it has at least one upper, at least one lower, at least one left and at least one right neighbor among this set's points.
Vasya marked quite many points on the paper. Analyzing the picture manually is rather a challenge, so Vasya asked you to help him. Your task is to find the number of supercentral points in the given set. | The first input line contains the only integer *n* (1<=β€<=*n*<=β€<=200) β the number of points in the given set. Next *n* lines contain the coordinates of the points written as "*x* *y*" (without the quotes) (|*x*|,<=|*y*|<=β€<=1000), all coordinates are integers. The numbers in the line are separated by exactly one space. It is guaranteed that all points are different. | Print the only number β the number of supercentral points of the given set. | [
"8\n1 1\n4 2\n3 1\n1 2\n0 2\n0 1\n1 0\n1 3\n",
"5\n0 0\n0 1\n1 0\n0 -1\n-1 0\n"
] | [
"2\n",
"1\n"
] | In the first sample the supercentral points are only points (1,β1) and (1,β2).
In the second sample there is one supercental point β point (0,β0). | [
{
"input": "8\n1 1\n4 2\n3 1\n1 2\n0 2\n0 1\n1 0\n1 3",
"output": "2"
},
{
"input": "5\n0 0\n0 1\n1 0\n0 -1\n-1 0",
"output": "1"
},
{
"input": "9\n-565 -752\n-184 723\n-184 -752\n-184 1\n950 723\n-565 723\n950 -752\n950 1\n-565 1",
"output": "1"
},
{
"input": "25\n-651 897\n... | 154 | 0 | 0 | 949 | |
797 | Array Queries | [
"brute force",
"data structures",
"dp"
] | null | null | *a* is an array of *n* positive integers, all of which are not greater than *n*.
You have to process *q* queries to this array. Each query is represented by two numbers *p* and *k*. Several operations are performed in each query; each operation changes *p* to *p*<=+<=*a**p*<=+<=*k*. There operations are applied until *p* becomes greater than *n*. The answer to the query is the number of performed operations. | The first line contains one integer *n* (1<=β€<=*n*<=β€<=100000).
The second line contains *n* integers β elements of *a* (1<=β€<=*a**i*<=β€<=*n* for each *i* from 1 to *n*).
The third line containts one integer *q* (1<=β€<=*q*<=β€<=100000).
Then *q* lines follow. Each line contains the values of *p* and *k* for corresponding query (1<=β€<=*p*,<=*k*<=β€<=*n*). | Print *q* integers, *i*th integer must be equal to the answer to *i*th query. | [
"3\n1 1 1\n3\n1 1\n2 1\n3 1\n"
] | [
"2\n1\n1\n"
] | Consider first example:
In first query after first operation *p*β=β3, after second operation *p*β=β5.
In next two queries *p* is greater than *n* after the first operation. | [
{
"input": "3\n1 1 1\n3\n1 1\n2 1\n3 1",
"output": "2\n1\n1"
},
{
"input": "10\n3 5 4 3 7 10 6 7 2 3\n10\n4 5\n2 10\n4 6\n9 9\n9 2\n5 1\n6 4\n1 1\n5 6\n6 4",
"output": "1\n1\n1\n1\n1\n1\n1\n2\n1\n1"
},
{
"input": "50\n6 2 5 6 10 2 5 8 9 2 9 5 10 4 3 6 10 6 1 1 3 7 2 1 7 8 5 9 6 2 7 6 1 7... | 2,000 | 15,769,600 | 0 | 950 | |
520 | Pangram | [
"implementation",
"strings"
] | null | null | A word or a sentence in some language is called a pangram if all the characters of the alphabet of this language appear in it at least once. Pangrams are often used to demonstrate fonts in printing or test the output devices.
You are given a string consisting of lowercase and uppercase Latin letters. Check whether this string is a pangram. We say that the string contains a letter of the Latin alphabet if this letter occurs in the string in uppercase or lowercase. | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=100)Β β the number of characters in the string.
The second line contains the string. The string consists only of uppercase and lowercase Latin letters. | Output "YES", if the string is a pangram and "NO" otherwise. | [
"12\ntoosmallword\n",
"35\nTheQuickBrownFoxJumpsOverTheLazyDog\n"
] | [
"NO\n",
"YES\n"
] | none | [
{
"input": "12\ntoosmallword",
"output": "NO"
},
{
"input": "35\nTheQuickBrownFoxJumpsOverTheLazyDog",
"output": "YES"
},
{
"input": "1\na",
"output": "NO"
},
{
"input": "26\nqwertyuiopasdfghjklzxcvbnm",
"output": "YES"
},
{
"input": "26\nABCDEFGHIJKLMNOPQRSTUVWXY... | 62 | 921,600 | 3 | 952 | |
755 | PolandBall and White-Red graph | [
"constructive algorithms",
"graphs",
"shortest paths"
] | null | null | PolandBall has an undirected simple graph consisting of *n* vertices. Unfortunately, it has no edges. The graph is very sad because of that. PolandBall wanted to make it happier, adding some red edges. Then, he will add white edges in every remaining place. Therefore, the final graph will be a clique in two colors: white and red.
Colorfulness of the graph is a value *min*(*d**r*,<=*d**w*), where *d**r* is the diameter of the red subgraph and *d**w* is the diameter of white subgraph. The diameter of a graph is a largest value *d* such that shortest path between some pair of vertices in it is equal to *d*. If the graph is not connected, we consider its diameter to be -1.
PolandBall wants the final graph to be as neat as possible. He wants the final colorfulness to be equal to *k*. Can you help him and find any graph which satisfies PolandBall's requests? | The only one input line contains two integers *n* and *k* (2<=β€<=*n*<=β€<=1000, 1<=β€<=*k*<=β€<=1000), representing graph's size and sought colorfulness. | If it's impossible to find a suitable graph, print -1.
Otherwise, you can output any graph which fulfills PolandBall's requirements. First, output *m*Β β the number of red edges in your graph. Then, you should output *m* lines, each containing two integers *a**i* and *b**i*, (1<=β€<=*a**i*,<=*b**i*<=β€<=*n*, *a**i*<=β <=*b**i*) which means that there is an undirected red edge between vertices *a**i* and *b**i*. Every red edge should be printed exactly once, you can print the edges and the vertices of every edge in arbitrary order.
Remember that PolandBall's graph should remain simple, so no loops or multiple edges are allowed. | [
"4 1\n",
"5 2\n"
] | [
"-1\n",
"4\n1 2\n2 3\n3 4\n4 5\n"
] | In the first sample case, no graph can fulfill PolandBall's requirements.
In the second sample case, red graph is a path from 1 to 5. Its diameter is 4. However, white graph has diameter 2, because it consists of edges 1-3, 1-4, 1-5, 2-4, 2-5, 3-5. | [
{
"input": "4 1",
"output": "-1"
},
{
"input": "5 2",
"output": "4\n1 2\n2 3\n3 4\n4 5"
},
{
"input": "500 3",
"output": "123755\n1 2\n499 500\n2 3\n2 4\n2 5\n2 6\n2 7\n2 8\n2 9\n2 10\n2 11\n2 12\n2 13\n2 14\n2 15\n2 16\n2 17\n2 18\n2 19\n2 20\n2 21\n2 22\n2 23\n2 24\n2 25\n2 26\n2 2... | 155 | 2,662,400 | 3 | 955 | |
460 | Present | [
"binary search",
"data structures",
"greedy"
] | null | null | Little beaver is a beginner programmer, so informatics is his favorite subject. Soon his informatics teacher is going to have a birthday and the beaver has decided to prepare a present for her. He planted *n* flowers in a row on his windowsill and started waiting for them to grow. However, after some time the beaver noticed that the flowers stopped growing. The beaver thinks it is bad manners to present little flowers. So he decided to come up with some solutions.
There are *m* days left to the birthday. The height of the *i*-th flower (assume that the flowers in the row are numbered from 1 to *n* from left to right) is equal to *a**i* at the moment. At each of the remaining *m* days the beaver can take a special watering and water *w* contiguous flowers (he can do that only once at a day). At that each watered flower grows by one height unit on that day. The beaver wants the height of the smallest flower be as large as possible in the end. What maximum height of the smallest flower can he get? | The first line contains space-separated integers *n*, *m* and *w* (1<=β€<=*w*<=β€<=*n*<=β€<=105;Β 1<=β€<=*m*<=β€<=105). The second line contains space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=109). | Print a single integer β the maximum final height of the smallest flower. | [
"6 2 3\n2 2 2 2 1 1\n",
"2 5 1\n5 8\n"
] | [
"2\n",
"9\n"
] | In the first sample beaver can water the last 3 flowers at the first day. On the next day he may not to water flowers at all. In the end he will get the following heights: [2, 2, 2, 3, 2, 2]. The smallest flower has height equal to 2. It's impossible to get height 3 in this test. | [
{
"input": "6 2 3\n2 2 2 2 1 1",
"output": "2"
},
{
"input": "2 5 1\n5 8",
"output": "9"
},
{
"input": "1 1 1\n1",
"output": "2"
},
{
"input": "3 2 3\n999999998 999999998 999999998",
"output": "1000000000"
},
{
"input": "10 8 3\n499 498 497 497 497 497 497 497 498... | 31 | 0 | 0 | 956 | |
598 | Tricky Sum | [
"math"
] | null | null | In this problem you are to calculate the sum of all integers from 1 to *n*, but you should take all powers of two with minus in the sum.
For example, for *n*<==<=4 the sum is equal to <=-<=1<=-<=2<=+<=3<=-<=4<==<=<=-<=4, because 1, 2 and 4 are 20, 21 and 22 respectively.
Calculate the answer for *t* values of *n*. | The first line of the input contains a single integer *t* (1<=β€<=*t*<=β€<=100) β the number of values of *n* to be processed.
Each of next *t* lines contains a single integer *n* (1<=β€<=*n*<=β€<=109). | Print the requested sum for each of *t* integers *n* given in the input. | [
"2\n4\n1000000000\n"
] | [
"-4\n499999998352516354\n"
] | The answer for the first sample is explained in the statement. | [
{
"input": "2\n4\n1000000000",
"output": "-4\n499999998352516354"
},
{
"input": "10\n1\n2\n3\n4\n5\n6\n7\n8\n9\n10",
"output": "-1\n-3\n0\n-4\n1\n7\n14\n6\n15\n25"
},
{
"input": "10\n10\n9\n47\n33\n99\n83\n62\n1\n100\n53",
"output": "25\n15\n1002\n435\n4696\n3232\n1827\n-1\n4796\n130... | 1,000 | 6,758,400 | 0 | 959 | |
262 | Roma and Lucky Numbers | [
"implementation"
] | null | null | Roma (a popular Russian name that means 'Roman') loves the Little Lvov Elephant's lucky numbers.
Let us remind you that lucky numbers are positive integers whose decimal representation only contains lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.
Roma's got *n* positive integers. He wonders, how many of those integers have not more than *k* lucky digits? Help him, write the program that solves the problem. | The first line contains two integers *n*, *k* (1<=β€<=*n*,<=*k*<=β€<=100). The second line contains *n* integers *a**i* (1<=β€<=*a**i*<=β€<=109) β the numbers that Roma has.
The numbers in the lines are separated by single spaces. | In a single line print a single integer β the answer to the problem. | [
"3 4\n1 2 4\n",
"3 2\n447 44 77\n"
] | [
"3\n",
"2\n"
] | In the first sample all numbers contain at most four lucky digits, so the answer is 3.
In the second sample number 447 doesn't fit in, as it contains more than two lucky digits. All other numbers are fine, so the answer is 2. | [
{
"input": "3 4\n1 2 4",
"output": "3"
},
{
"input": "3 2\n447 44 77",
"output": "2"
},
{
"input": "2 2\n507978501 180480073",
"output": "2"
},
{
"input": "9 6\n655243746 167613748 1470546 57644035 176077477 56984809 44677 215706823 369042089",
"output": "9"
},
{
... | 280 | 0 | 3 | 962 | |
254 | Cards with Numbers | [
"constructive algorithms",
"sortings"
] | null | null | Petya has got 2*n* cards, each card contains some integer. The numbers on the cards can be the same. Let's index all cards by consecutive integers from 1 to 2*n*. We'll denote the number that is written on a card with number *i*, as *a**i*. In order to play one entertaining game with his friends, Petya needs to split the cards into pairs so that each pair had equal numbers on the cards. Help Petya do that. | The first line contains integer *n* (1<=β€<=*n*<=β€<=3Β·105). The second line contains the sequence of 2*n* positive integers *a*1,<=*a*2,<=...,<=*a*2*n* (1<=β€<=*a**i*<=β€<=5000) β the numbers that are written on the cards. The numbers on the line are separated by single spaces. | If it is impossible to divide the cards into pairs so that cards in each pair had the same numbers, print on a single line integer -1. But if the required partition exists, then print *n* pairs of integers, a pair per line β the indices of the cards that form the pairs.
Separate the numbers on the lines by spaces. You can print the pairs and the numbers in the pairs in any order. If there are multiple solutions, print any of them. | [
"3\n20 30 10 30 20 10\n",
"1\n1 2\n"
] | [
"4 2\n1 5\n6 3\n",
"-1"
] | none | [
{
"input": "3\n20 30 10 30 20 10",
"output": "4 2\n1 5\n6 3"
},
{
"input": "1\n1 2",
"output": "-1"
},
{
"input": "5\n2 2 2 2 2 1 2 2 1 2",
"output": "2 1\n3 4\n7 5\n6 9\n10 8"
},
{
"input": "5\n2 1 2 2 1 1 1 1 1 2",
"output": "3 1\n2 5\n7 6\n8 9\n10 4"
},
{
"inpu... | 686 | 45,465,600 | 3 | 963 | |
448 | Rewards | [
"implementation"
] | null | null | Bizon the Champion is called the Champion for a reason.
Bizon the Champion has recently got a present β a new glass cupboard with *n* shelves and he decided to put all his presents there. All the presents can be divided into two types: medals and cups. Bizon the Champion has *a*1 first prize cups, *a*2 second prize cups and *a*3 third prize cups. Besides, he has *b*1 first prize medals, *b*2 second prize medals and *b*3 third prize medals.
Naturally, the rewards in the cupboard must look good, that's why Bizon the Champion decided to follow the rules:
- any shelf cannot contain both cups and medals at the same time; - no shelf can contain more than five cups; - no shelf can have more than ten medals.
Help Bizon the Champion find out if we can put all the rewards so that all the conditions are fulfilled. | The first line contains integers *a*1, *a*2 and *a*3 (0<=β€<=*a*1,<=*a*2,<=*a*3<=β€<=100). The second line contains integers *b*1, *b*2 and *b*3 (0<=β€<=*b*1,<=*b*2,<=*b*3<=β€<=100). The third line contains integer *n* (1<=β€<=*n*<=β€<=100).
The numbers in the lines are separated by single spaces. | Print "YES" (without the quotes) if all the rewards can be put on the shelves in the described manner. Otherwise, print "NO" (without the quotes). | [
"1 1 1\n1 1 1\n4\n",
"1 1 3\n2 3 4\n2\n",
"1 0 0\n1 0 0\n1\n"
] | [
"YES\n",
"YES\n",
"NO\n"
] | none | [
{
"input": "1 1 1\n1 1 1\n4",
"output": "YES"
},
{
"input": "1 1 3\n2 3 4\n2",
"output": "YES"
},
{
"input": "1 0 0\n1 0 0\n1",
"output": "NO"
},
{
"input": "0 0 0\n0 0 0\n1",
"output": "YES"
},
{
"input": "100 100 100\n100 100 100\n100",
"output": "YES"
},
... | 46 | 0 | 3 | 964 | |
549 | Sasha Circle | [
"geometry",
"math"
] | null | null | Berlanders like to eat cones after a hard day. Misha Square and Sasha Circle are local authorities of Berland. Each of them controls its points of cone trade. Misha has *n* points, Sasha β *m*. Since their subordinates constantly had conflicts with each other, they decided to build a fence in the form of a circle, so that the points of trade of one businessman are strictly inside a circle, and points of the other one are strictly outside. It doesn't matter which of the two gentlemen will have his trade points inside the circle.
Determine whether they can build a fence or not. | The first line contains two integers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=10000), numbers of Misha's and Sasha's trade points respectively.
The next *n* lines contains pairs of space-separated integers *M**x*,<=*M**y* (<=-<=104<=β€<=*M**x*,<=*M**y*<=β€<=104), coordinates of Misha's trade points.
The next *m* lines contains pairs of space-separated integers *S**x*,<=*S**y* (<=-<=104<=β€<=*S**x*,<=*S**y*<=β€<=104), coordinates of Sasha's trade points.
It is guaranteed that all *n*<=+<=*m* points are distinct. | The only output line should contain either word "YES" without quotes in case it is possible to build a such fence or word "NO" in the other case. | [
"2 2\n-1 0\n1 0\n0 -1\n0 1\n",
"4 4\n1 0\n0 1\n-1 0\n0 -1\n1 1\n-1 1\n-1 -1\n1 -1\n"
] | [
"NO\n",
"YES\n"
] | In the first sample there is no possibility to separate points, because any circle that contains both points (β-β1,β0),β(1,β0) also contains at least one point from the set (0,ββ-β1),β(0,β1), and vice-versa: any circle that contains both points (0,ββ-β1),β(0,β1) also contains at least one point from the set (β-β1,β0),β(1,β0)
In the second sample one of the possible solution is shown below. Misha's points are marked with red colour and Sasha's are marked with blue. <img class="tex-graphics" src="https://espresso.codeforces.com/91e76198f6d74c0a8b0f92c94460d887bfebc9fa.png" style="max-width: 100.0%;max-height: 100.0%;"/> | [
{
"input": "2 2\n-1 0\n1 0\n0 -1\n0 1",
"output": "NO"
},
{
"input": "4 4\n1 0\n0 1\n-1 0\n0 -1\n1 1\n-1 1\n-1 -1\n1 -1",
"output": "YES"
},
{
"input": "2 3\n-1 0\n1 0\n0 -2\n0 0\n0 2",
"output": "NO"
},
{
"input": "3 3\n-3 -4\n3 2\n1 5\n4 0\n5 2\n-2 -1",
"output": "NO"
... | 31 | 0 | 0 | 966 | |
961 | Tetris | [
"implementation"
] | null | null | You are given a following process.
There is a platform with $n$ columns. $1 \times 1$ squares are appearing one after another in some columns on this platform. If there are no squares in the column, a square will occupy the bottom row. Otherwise a square will appear at the top of the highest square of this column.
When all of the $n$ columns have at least one square in them, the bottom row is being removed. You will receive $1$ point for this, and all the squares left will fall down one row.
You task is to calculate the amount of points you will receive. | The first line of input contain 2 integer numbers $n$ and $m$ ($1 \le n, m \le 1000$) β the length of the platform and the number of the squares.
The next line contain $m$ integer numbers $c_1, c_2, \dots, c_m$ ($1 \le c_i \le n$) β column in which $i$-th square will appear. | Print one integer β the amount of points you will receive. | [
"3 9\n1 1 2 2 2 3 1 2 3\n"
] | [
"2\n"
] | In the sample case the answer will be equal to $2$ because after the appearing of $6$-th square will be removed one row (counts of the squares on the platform will look like $[2~ 3~ 1]$, and after removing one row will be $[1~ 2~ 0]$).
After the appearing of $9$-th square counts will be $[2~ 3~ 1]$, and after removing one row it will look like $[1~ 2~ 0]$.
So the answer will be equal to $2$. | [
{
"input": "3 9\n1 1 2 2 2 3 1 2 3",
"output": "2"
},
{
"input": "1 7\n1 1 1 1 1 1 1",
"output": "7"
},
{
"input": "1 1\n1",
"output": "1"
},
{
"input": "3 5\n1 1 1 2 3",
"output": "1"
},
{
"input": "4 6\n4 4 4 4 4 4",
"output": "0"
},
{
"input": "4 6\... | 109 | 0 | 3 | 967 | |
350 | TL | [
"brute force",
"greedy",
"implementation"
] | null | null | Valera wanted to prepare a Codesecrof round. He's already got one problem and he wants to set a time limit (TL) on it.
Valera has written *n* correct solutions. For each correct solution, he knows its running time (in seconds). Valera has also wrote *m* wrong solutions and for each wrong solution he knows its running time (in seconds).
Let's suppose that Valera will set *v* seconds TL in the problem. Then we can say that a solution passes the system testing if its running time is at most *v* seconds. We can also say that a solution passes the system testing with some "extra" time if for its running time, *a* seconds, an inequality 2*a*<=β€<=*v* holds.
As a result, Valera decided to set *v* seconds TL, that the following conditions are met:
1. *v* is a positive integer; 1. all correct solutions pass the system testing; 1. at least one correct solution passes the system testing with some "extra" time; 1. all wrong solutions do not pass the system testing; 1. value *v* is minimum among all TLs, for which points 1, 2, 3, 4 hold.
Help Valera and find the most suitable TL or else state that such TL doesn't exist. | The first line contains two integers *n*, *m* (1<=β€<=*n*,<=*m*<=β€<=100). The second line contains *n* space-separated positive integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=100) β the running time of each of the *n* correct solutions in seconds. The third line contains *m* space-separated positive integers *b*1,<=*b*2,<=...,<=*b**m* (1<=β€<=*b**i*<=β€<=100) β the running time of each of *m* wrong solutions in seconds. | If there is a valid TL value, print it. Otherwise, print -1. | [
"3 6\n4 5 2\n8 9 6 10 7 11\n",
"3 1\n3 4 5\n6\n"
] | [
"5",
"-1\n"
] | none | [
{
"input": "3 6\n4 5 2\n8 9 6 10 7 11",
"output": "5"
},
{
"input": "3 1\n3 4 5\n6",
"output": "-1"
},
{
"input": "2 5\n45 99\n49 41 77 83 45",
"output": "-1"
},
{
"input": "50 50\n18 13 5 34 10 36 36 12 15 11 16 17 14 36 23 45 32 24 31 18 24 32 7 1 31 3 49 8 16 23 3 39 47 43... | 92 | 4,608,000 | 0 | 970 | |
16 | Flag | [
"implementation"
] | A. Flag | 2 | 64 | According to a new ISO standard, a flag of every country should have a chequered field *n*<=Γ<=*m*, each square should be of one of 10 colours, and the flag should be Β«stripedΒ»: each horizontal row of the flag should contain squares of the same colour, and the colours of adjacent horizontal rows should be different. Berland's government asked you to find out whether their flag meets the new ISO standard. | The first line of the input contains numbers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=100), *n* β the amount of rows, *m* β the amount of columns on the flag of Berland. Then there follows the description of the flag: each of the following *n* lines contain *m* characters. Each character is a digit between 0 and 9, and stands for the colour of the corresponding square. | Output YES, if the flag meets the new ISO standard, and NO otherwise. | [
"3 3\n000\n111\n222\n",
"3 3\n000\n000\n111\n",
"3 3\n000\n111\n002\n"
] | [
"YES\n",
"NO\n",
"NO\n"
] | none | [
{
"input": "3 3\n000\n111\n222",
"output": "YES"
},
{
"input": "3 3\n000\n000\n111",
"output": "NO"
},
{
"input": "3 3\n000\n111\n002",
"output": "NO"
},
{
"input": "10 10\n2222222222\n5555555555\n0000000000\n4444444444\n1111111111\n3333333393\n3333333333\n5555555555\n0000000... | 92 | 0 | 0 | 971 |
215 | Olympic Medal | [
"greedy",
"math"
] | null | null | The World Programming Olympics Medal is a metal disk, consisting of two parts: the first part is a ring with outer radius of *r*1 cm, inner radius of *r*2 cm, (0<=<<=*r*2<=<<=*r*1) made of metal with density *p*1 g/cm3. The second part is an inner disk with radius *r*2 cm, it is made of metal with density *p*2 g/cm3. The disk is nested inside the ring.
The Olympic jury decided that *r*1 will take one of possible values of *x*1,<=*x*2,<=...,<=*x**n*. It is up to jury to decide which particular value *r*1 will take. Similarly, the Olympic jury decided that *p*1 will take one of possible value of *y*1,<=*y*2,<=...,<=*y**m*, and *p*2 will take a value from list *z*1,<=*z*2,<=...,<=*z**k*.
According to most ancient traditions the ratio between the outer ring mass *m**out* and the inner disk mass *m**in* must equal , where *A*,<=*B* are constants taken from ancient books. Now, to start making medals, the jury needs to take values for *r*1, *p*1, *p*2 and calculate the suitable value of *r*2.
The jury wants to choose the value that would maximize radius *r*2. Help the jury find the sought value of *r*2. Value *r*2 doesn't have to be an integer.
Medal has a uniform thickness throughout the area, the thickness of the inner disk is the same as the thickness of the outer ring. | The first input line contains an integer *n* and a sequence of integers *x*1,<=*x*2,<=...,<=*x**n*. The second input line contains an integer *m* and a sequence of integers *y*1,<=*y*2,<=...,<=*y**m*. The third input line contains an integer *k* and a sequence of integers *z*1,<=*z*2,<=...,<=*z**k*. The last line contains two integers *A* and *B*.
All numbers given in the input are positive and do not exceed 5000. Each of the three sequences contains distinct numbers. The numbers in the lines are separated by spaces. | Print a single real number β the sought value *r*2 with absolute or relative error of at most 10<=-<=6. It is guaranteed that the solution that meets the problem requirements exists. | [
"3 1 2 3\n1 2\n3 3 2 1\n1 2\n",
"4 2 3 6 4\n2 1 2\n3 10 6 8\n2 1\n"
] | [
"2.683281573000\n",
"2.267786838055\n"
] | In the first sample the jury should choose the following values: *r*<sub class="lower-index">1</sub>β=β3, *p*<sub class="lower-index">1</sub>β=β2, *p*<sub class="lower-index">2</sub>β=β1. | [
{
"input": "3 1 2 3\n1 2\n3 3 2 1\n1 2",
"output": "2.683281573000"
},
{
"input": "4 2 3 6 4\n2 1 2\n3 10 6 8\n2 1",
"output": "2.267786838055"
},
{
"input": "1 5\n1 3\n1 7\n515 892",
"output": "3.263613058533"
},
{
"input": "2 3 2\n3 2 3 1\n2 2 1\n733 883",
"output": "2.... | 156 | 921,600 | 3 | 972 | |
397 | On Segment's Own Points | [
"implementation"
] | null | null | Our old friend Alexey has finally entered the University of City N β the Berland capital. Alexey expected his father to get him a place to live in but his father said it was high time for Alexey to practice some financial independence. So, Alexey is living in a dorm.
The dorm has exactly one straight dryer β a 100 centimeter long rope to hang clothes on. The dryer has got a coordinate system installed: the leftmost end of the dryer has coordinate 0, and the opposite end has coordinate 100. Overall, the university has *n* students. Dean's office allows *i*-th student to use the segment (*l**i*,<=*r**i*) of the dryer. However, the dean's office actions are contradictory and now one part of the dryer can belong to multiple students!
Alexey don't like when someone touch his clothes. That's why he want make it impossible to someone clothes touch his ones. So Alexey wonders: what is the total length of the parts of the dryer that he may use in a such way that clothes of the others (*n*<=-<=1) students aren't drying there. Help him! Note that Alexey, as the most respected student, has number 1. | The first line contains a positive integer *n* (1<=β€<=*n*<=β€<=100). The (*i*<=+<=1)-th line contains integers *l**i* and *r**i* (0<=β€<=*l**i*<=<<=*r**i*<=β€<=100) βΒ the endpoints of the corresponding segment for the *i*-th student. | On a single line print a single number *k*, equal to the sum of lengths of the parts of the dryer which are inside Alexey's segment and are outside all other segments. | [
"3\n0 5\n2 8\n1 6\n",
"3\n0 10\n1 5\n7 15\n"
] | [
"1\n",
"3\n"
] | Note that it's not important are clothes drying on the touching segments (e.g. (0,β1) and (1,β2)) considered to be touching or not because you need to find the length of segments.
In the first test sample Alexey may use the only segment (0,β1). In such case his clothes will not touch clothes on the segments (1,β6) and (2,β8). The length of segment (0,β1) is 1.
In the second test sample Alexey may dry his clothes on segments (0,β1) and (5,β7). Overall length of these segments is 3. | [
{
"input": "3\n0 5\n2 8\n1 6",
"output": "1"
},
{
"input": "3\n0 10\n1 5\n7 15",
"output": "3"
},
{
"input": "1\n0 100",
"output": "100"
},
{
"input": "2\n1 9\n1 9",
"output": "0"
},
{
"input": "2\n1 9\n5 10",
"output": "4"
},
{
"input": "2\n1 9\n3 5",... | 30 | 0 | 0 | 975 | |
569 | Inventory | [
"greedy",
"math"
] | null | null | Companies always have a lot of equipment, furniture and other things. All of them should be tracked. To do this, there is an inventory number assigned with each item. It is much easier to create a database by using those numbers and keep the track of everything.
During an audit, you were surprised to find out that the items are not numbered sequentially, and some items even share the same inventory number! There is an urgent need to fix it. You have chosen to make the numbers of the items sequential, starting with 1. Changing a number is quite a time-consuming process, and you would like to make maximum use of the current numbering.
You have been given information on current inventory numbers for *n* items in the company. Renumber items so that their inventory numbers form a permutation of numbers from 1 to *n* by changing the number of as few items as possible. Let us remind you that a set of *n* numbers forms a permutation if all the numbers are in the range from 1 to *n*, and no two numbers are equal. | The first line contains a single integer *n*Β β the number of items (1<=β€<=*n*<=β€<=105).
The second line contains *n* numbers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=105)Β β the initial inventory numbers of the items. | Print *n* numbersΒ β the final inventory numbers of the items in the order they occur in the input. If there are multiple possible answers, you may print any of them. | [
"3\n1 3 2\n",
"4\n2 2 3 3\n",
"1\n2\n"
] | [
"1 3 2 \n",
"2 1 3 4 \n",
"1 \n"
] | In the first test the numeration is already a permutation, so there is no need to change anything.
In the second test there are two pairs of equal numbers, in each pair you need to replace one number.
In the third test you need to replace 2 by 1, as the numbering should start from one. | [
{
"input": "3\n1 3 2",
"output": "1 3 2 "
},
{
"input": "4\n2 2 3 3",
"output": "2 1 3 4 "
},
{
"input": "1\n2",
"output": "1 "
},
{
"input": "3\n3 3 1",
"output": "3 2 1 "
},
{
"input": "5\n1 1 1 1 1",
"output": "1 2 3 4 5 "
},
{
"input": "5\n5 3 4 4 ... | 124 | 0 | 0 | 980 | |
625 | War of the Corporations | [
"constructive algorithms",
"greedy",
"strings"
] | null | null | A long time ago, in a galaxy far far away two giant IT-corporations Pineapple and Gogol continue their fierce competition. Crucial moment is just around the corner: Gogol is ready to release it's new tablet Lastus 3000.
This new device is equipped with specially designed artificial intelligence (AI). Employees of Pineapple did their best to postpone the release of Lastus 3000 as long as possible. Finally, they found out, that the name of the new artificial intelligence is similar to the name of the phone, that Pineapple released 200 years ago. As all rights on its name belong to Pineapple, they stand on changing the name of Gogol's artificial intelligence.
Pineapple insists, that the name of their phone occurs in the name of AI as a substring. Because the name of technology was already printed on all devices, the Gogol's director decided to replace some characters in AI name with "#". As this operation is pretty expensive, you should find the minimum number of characters to replace with "#", such that the name of AI doesn't contain the name of the phone as a substring.
Substring is a continuous subsequence of a string. | The first line of the input contains the name of AI designed by Gogol, its length doesn't exceed 100<=000 characters. Second line contains the name of the phone released by Pineapple 200 years ago, its length doesn't exceed 30. Both string are non-empty and consist of only small English letters. | Print the minimum number of characters that must be replaced with "#" in order to obtain that the name of the phone doesn't occur in the name of AI as a substring. | [
"intellect\ntell\n",
"google\napple\n",
"sirisiri\nsir\n"
] | [
"1",
"0",
"2"
] | In the first sample AI's name may be replaced with "int#llect".
In the second sample Gogol can just keep things as they are.
In the third sample one of the new possible names of AI may be "s#ris#ri". | [
{
"input": "intellect\ntell",
"output": "1"
},
{
"input": "google\napple",
"output": "0"
},
{
"input": "sirisiri\nsir",
"output": "2"
},
{
"input": "sirisiri\nsiri",
"output": "2"
},
{
"input": "aaaaaaa\naaaa",
"output": "1"
},
{
"input": "bbbbbb\nbb",... | 62 | 4,915,200 | 3 | 982 | |
765 | Code obfuscation | [
"greedy",
"implementation",
"strings"
] | null | null | Kostya likes Codeforces contests very much. However, he is very disappointed that his solutions are frequently hacked. That's why he decided to obfuscate (intentionally make less readable) his code before upcoming contest.
To obfuscate the code, Kostya first looks at the first variable name used in his program and replaces all its occurrences with a single symbol *a*, then he looks at the second variable name that has not been replaced yet, and replaces all its occurrences with *b*, and so on. Kostya is well-mannered, so he doesn't use any one-letter names before obfuscation. Moreover, there are at most 26 unique identifiers in his programs.
You are given a list of identifiers of some program with removed spaces and line breaks. Check if this program can be a result of Kostya's obfuscation. | In the only line of input there is a string *S* of lowercase English letters (1<=β€<=|*S*|<=β€<=500)Β β the identifiers of a program with removed whitespace characters. | If this program can be a result of Kostya's obfuscation, print "YES" (without quotes), otherwise print "NO". | [
"abacaba\n",
"jinotega\n"
] | [
"YES\n",
"NO\n"
] | In the first sample case, one possible list of identifiers would be "number string number character number string number". Here how Kostya would obfuscate the program:
- replace all occurences of number with a, the result would be "a string a character a string a",- replace all occurences of string with b, the result would be "a b a character a b a",- replace all occurences of character with c, the result would be "a b a c a b a",- all identifiers have been replaced, thus the obfuscation is finished. | [
{
"input": "abacaba",
"output": "YES"
},
{
"input": "jinotega",
"output": "NO"
},
{
"input": "aaaaaaaaaaa",
"output": "YES"
},
{
"input": "aba",
"output": "YES"
},
{
"input": "bab",
"output": "NO"
},
{
"input": "a",
"output": "YES"
},
{
"in... | 77 | 7,065,600 | 0 | 984 | |
9 | Hexadecimal's Numbers | [
"brute force",
"implementation",
"math"
] | C. Hexadecimal's Numbers | 1 | 64 | One beautiful July morning a terrible thing happened in Mainframe: a mean virus Megabyte somehow got access to the memory of his not less mean sister Hexadecimal. He loaded there a huge amount of *n* different natural numbers from 1 to *n* to obtain total control over her energy.
But his plan failed. The reason for this was very simple: Hexadecimal didn't perceive any information, apart from numbers written in binary format. This means that if a number in a decimal representation contained characters apart from 0 and 1, it was not stored in the memory. Now Megabyte wants to know, how many numbers were loaded successfully. | Input data contains the only number *n* (1<=β€<=*n*<=β€<=109). | Output the only number β answer to the problem. | [
"10\n"
] | [
"2"
] | For *n* = 10 the answer includes numbers 1 and 10. | [
{
"input": "10",
"output": "2"
},
{
"input": "20",
"output": "3"
},
{
"input": "72",
"output": "3"
},
{
"input": "99",
"output": "3"
},
{
"input": "100",
"output": "4"
},
{
"input": "101",
"output": "5"
},
{
"input": "102",
"output": "5... | 186 | 0 | -1 | 986 |
794 | Naming Company | [
"games",
"greedy",
"sortings"
] | null | null | Oleg the client and Igor the analyst are good friends. However, sometimes they argue over little things. Recently, they started a new company, but they are having trouble finding a name for the company.
To settle this problem, they've decided to play a game. The company name will consist of *n* letters. Oleg and Igor each have a set of *n* letters (which might contain multiple copies of the same letter, the sets can be different). Initially, the company name is denoted by *n* question marks. Oleg and Igor takes turns to play the game, Oleg moves first. In each turn, a player can choose one of the letters *c* in his set and replace any of the question marks with *c*. Then, a copy of the letter *c* is removed from his set. The game ends when all the question marks has been replaced by some letter.
For example, suppose Oleg has the set of letters {*i*,<=*o*,<=*i*} and Igor has the set of letters {*i*,<=*m*,<=*o*}. One possible game is as follows :
Initially, the company name is ???.
Oleg replaces the second question mark with 'i'. The company name becomes ?i?. The set of letters Oleg have now is {*i*,<=*o*}.
Igor replaces the third question mark with 'o'. The company name becomes ?io. The set of letters Igor have now is {*i*,<=*m*}.
Finally, Oleg replaces the first question mark with 'o'. The company name becomes oio. The set of letters Oleg have now is {*i*}.
In the end, the company name is oio.
Oleg wants the company name to be as lexicographically small as possible while Igor wants the company name to be as lexicographically large as possible. What will be the company name if Oleg and Igor always play optimally?
A string *s*<==<=*s*1*s*2...*s**m* is called lexicographically smaller than a string *t*<==<=*t*1*t*2...*t**m* (where *s*<=β <=*t*) if *s**i*<=<<=*t**i* where *i* is the smallest index such that *s**i*<=β <=*t**i*. (so *s**j*<==<=*t**j* for all *j*<=<<=*i*) | The first line of input contains a string *s* of length *n* (1<=β€<=*n*<=β€<=3Β·105). All characters of the string are lowercase English letters. This string denotes the set of letters Oleg has initially.
The second line of input contains a string *t* of length *n*. All characters of the string are lowercase English letters. This string denotes the set of letters Igor has initially. | The output should contain a string of *n* lowercase English letters, denoting the company name if Oleg and Igor plays optimally. | [
"tinkoff\nzscoder\n",
"xxxxxx\nxxxxxx\n",
"ioi\nimo\n"
] | [
"fzfsirk\n",
"xxxxxx\n",
"ioi\n"
] | One way to play optimally in the first sample is as follows :
- Initially, the company name is ???????.- Oleg replaces the first question mark with 'f'. The company name becomes f??????.- Igor replaces the second question mark with 'z'. The company name becomes fz?????.- Oleg replaces the third question mark with 'f'. The company name becomes fzf????.- Igor replaces the fourth question mark with 's'. The company name becomes fzfs???.- Oleg replaces the fifth question mark with 'i'. The company name becomes fzfsi??.- Igor replaces the sixth question mark with 'r'. The company name becomes fzfsir?.- Oleg replaces the seventh question mark with 'k'. The company name becomes fzfsirk.
For the second sample, no matter how they play, the company name will always be xxxxxx. | [
{
"input": "tinkoff\nzscoder",
"output": "fzfsirk"
},
{
"input": "xxxxxx\nxxxxxx",
"output": "xxxxxx"
},
{
"input": "ioi\nimo",
"output": "ioi"
},
{
"input": "abc\naaa",
"output": "aab"
},
{
"input": "reddit\nabcdef",
"output": "dfdeed"
},
{
"input": "... | 483 | 7,065,600 | 3 | 989 | |
1 | Spreadsheet | [
"implementation",
"math"
] | B. Spreadsheets | 10 | 64 | In the popular spreadsheets systems (for example, in Excel) the following numeration of columns is used. The first column has number A, the second β number B, etc. till column 26 that is marked by Z. Then there are two-letter numbers: column 27 has number AA, 28 β AB, column 52 is marked by AZ. After ZZ there follow three-letter numbers, etc.
The rows are marked by integer numbers starting with 1. The cell name is the concatenation of the column and the row numbers. For example, BC23 is the name for the cell that is in column 55, row 23.
Sometimes another numeration system is used: RXCY, where X and Y are integer numbers, showing the column and the row numbers respectfully. For instance, R23C55 is the cell from the previous example.
Your task is to write a program that reads the given sequence of cell coordinates and produce each item written according to the rules of another numeration system. | The first line of the input contains integer number *n* (1<=β€<=*n*<=β€<=105), the number of coordinates in the test. Then there follow *n* lines, each of them contains coordinates. All the coordinates are correct, there are no cells with the column and/or the row numbers larger than 106 . | Write *n* lines, each line should contain a cell coordinates in the other numeration system. | [
"2\nR23C55\nBC23\n"
] | [
"BC23\nR23C55\n"
] | none | [
{
"input": "2\nR23C55\nBC23",
"output": "BC23\nR23C55"
},
{
"input": "1\nA1",
"output": "R1C1"
},
{
"input": "5\nR8C3\nD1\nR7C2\nR8C9\nR8C9",
"output": "C8\nR1C4\nB7\nI8\nI8"
},
{
"input": "4\nR4C25\nR90C35\nAP55\nX83",
"output": "Y4\nAI90\nR55C42\nR83C24"
},
{
"i... | 2,588 | 10,854,400 | 3.789728 | 990 |
404 | Valera and X | [
"implementation"
] | null | null | Valera is a little boy. Yesterday he got a huge Math hometask at school, so Valera didn't have enough time to properly learn the English alphabet for his English lesson. Unfortunately, the English teacher decided to have a test on alphabet today. At the test Valera got a square piece of squared paper. The length of the side equals *n* squares (*n* is an odd number) and each unit square contains some small letter of the English alphabet.
Valera needs to know if the letters written on the square piece of paper form letter "X". Valera's teacher thinks that the letters on the piece of paper form an "X", if:
- on both diagonals of the square paper all letters are the same; - all other squares of the paper (they are not on the diagonals) contain the same letter that is different from the letters on the diagonals.
Help Valera, write the program that completes the described task for him. | The first line contains integer *n* (3<=β€<=*n*<=<<=300; *n* is odd). Each of the next *n* lines contains *n* small English letters β the description of Valera's paper. | Print string "YES", if the letters on the paper form letter "X". Otherwise, print string "NO". Print the strings without quotes. | [
"5\nxooox\noxoxo\nsoxoo\noxoxo\nxooox\n",
"3\nwsw\nsws\nwsw\n",
"3\nxpx\npxp\nxpe\n"
] | [
"NO\n",
"YES\n",
"NO\n"
] | none | [
{
"input": "5\nxooox\noxoxo\nsoxoo\noxoxo\nxooox",
"output": "NO"
},
{
"input": "3\nwsw\nsws\nwsw",
"output": "YES"
},
{
"input": "3\nxpx\npxp\nxpe",
"output": "NO"
},
{
"input": "5\nliiil\nilili\niilii\nilili\nliiil",
"output": "YES"
},
{
"input": "7\nbwccccb\nck... | 46 | 0 | 3 | 991 | |
27 | Next Test | [
"implementation",
"sortings"
] | A. Next Test | 2 | 256 | Β«PolygonΒ» is a system which allows to create programming tasks in a simple and professional way. When you add a test to the problem, the corresponding form asks you for the test index. As in most cases it is clear which index the next test will have, the system suggests the default value of the index. It is calculated as the smallest positive integer which is not used as an index for some previously added test.
You are to implement this feature. Create a program which determines the default index of the next test, given the indexes of the previously added tests. | The first line contains one integer *n* (1<=β€<=*n*<=β€<=3000) β the amount of previously added tests. The second line contains *n* distinct integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=3000) β indexes of these tests. | Output the required default value for the next test index. | [
"3\n1 7 2\n"
] | [
"3\n"
] | none | [
{
"input": "1\n1",
"output": "2"
},
{
"input": "2\n2 1",
"output": "3"
},
{
"input": "3\n3 4 1",
"output": "2"
},
{
"input": "4\n6 4 3 5",
"output": "1"
},
{
"input": "5\n3 2 1 7 4",
"output": "5"
},
{
"input": "6\n4 1 2 5 3 7",
"output": "6"
},
... | 62 | 0 | 0 | 992 |
715 | Plus and Square Root | [
"constructive algorithms",
"math"
] | null | null | ZS the Coder is playing a game. There is a number displayed on the screen and there are two buttons, '<=+<=' (plus) and '' (square root). Initially, the number 2 is displayed on the screen. There are *n*<=+<=1 levels in the game and ZS the Coder start at the level 1.
When ZS the Coder is at level *k*, he can :
1. Press the '<=+<=' button. This increases the number on the screen by exactly *k*. So, if the number on the screen was *x*, it becomes *x*<=+<=*k*.1. Press the '' button. Let the number on the screen be *x*. After pressing this button, the number becomes . After that, ZS the Coder levels up, so his current level becomes *k*<=+<=1. This button can only be pressed when *x* is a perfect square, i.e. *x*<==<=*m*2 for some positive integer *m*.
Additionally, after each move, if ZS the Coder is at level *k*, and the number on the screen is *m*, then *m* must be a multiple of *k*. Note that this condition is only checked after performing the press. For example, if ZS the Coder is at level 4 and current number is 100, he presses the '' button and the number turns into 10. Note that at this moment, 10 is not divisible by 4, but this press is still valid, because after it, ZS the Coder is at level 5, and 10 is divisible by 5.
ZS the Coder needs your help in beating the gameΒ β he wants to reach level *n*<=+<=1. In other words, he needs to press the '' button *n* times. Help him determine the number of times he should press the '<=+<=' button before pressing the '' button at each level.
Please note that ZS the Coder wants to find just any sequence of presses allowing him to reach level *n*<=+<=1, but not necessarily a sequence minimizing the number of presses. | The first and only line of the input contains a single integer *n* (1<=β€<=*n*<=β€<=100<=000), denoting that ZS the Coder wants to reach level *n*<=+<=1. | Print *n* non-negative integers, one per line. *i*-th of them should be equal to the number of times that ZS the Coder needs to press the '<=+<=' button before pressing the '' button at level *i*.
Each number in the output should not exceed 1018. However, the number on the screen can be greater than 1018.
It is guaranteed that at least one solution exists. If there are multiple solutions, print any of them. | [
"3\n",
"2\n",
"4\n"
] | [
"14\n16\n46\n",
"999999999999999998\n44500000000\n",
"2\n17\n46\n97\n"
] | In the first sample case:
On the first level, ZS the Coder pressed the 'β+β' button 14 times (and the number on screen is initially 2), so the number became 2β+β14Β·1β=β16. Then, ZS the Coder pressed the '<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c77ded9b8209a8cb488cc2ec7b7fe1dae32a5309.png" style="max-width: 100.0%;max-height: 100.0%;"/>' button, and the number became <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c3d2663f5f74e9220fd5cbccbfaf4ca76ef7284f.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
After that, on the second level, ZS pressed the 'β+β' button 16 times, so the number becomes 4β+β16Β·2β=β36. Then, ZS pressed the '<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c77ded9b8209a8cb488cc2ec7b7fe1dae32a5309.png" style="max-width: 100.0%;max-height: 100.0%;"/>' button, levelling up and changing the number into <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/49ab1d31f1435b7c7b96550d63a35be671d3d85a.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
After that, on the third level, ZS pressed the 'β+β' button 46 times, so the number becomes 6β+β46Β·3β=β144. Then, ZS pressed the '<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c77ded9b8209a8cb488cc2ec7b7fe1dae32a5309.png" style="max-width: 100.0%;max-height: 100.0%;"/>' button, levelling up and changing the number into <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/499b57d4b7ba5e1e0957767cc182808ca48ef722.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
Note that 12 is indeed divisible by 4, so ZS the Coder can reach level 4.
Also, note that pressing the 'β+β' button 10 times on the third level before levelling up does not work, because the number becomes 6β+β10Β·3β=β36, and when the '<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c77ded9b8209a8cb488cc2ec7b7fe1dae32a5309.png" style="max-width: 100.0%;max-height: 100.0%;"/>' button is pressed, the number becomes <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/49ab1d31f1435b7c7b96550d63a35be671d3d85a.png" style="max-width: 100.0%;max-height: 100.0%;"/> and ZS the Coder is at Level 4. However, 6 is not divisible by 4 now, so this is not a valid solution.
In the second sample case:
On the first level, ZS the Coder pressed the 'β+β' button 999999999999999998 times (and the number on screen is initially 2), so the number became 2β+β999999999999999998Β·1β=β10<sup class="upper-index">18</sup>. Then, ZS the Coder pressed the '<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c77ded9b8209a8cb488cc2ec7b7fe1dae32a5309.png" style="max-width: 100.0%;max-height: 100.0%;"/>' button, and the number became <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/f07f2a60ab6cecbd2507861a0df57a16a015fd86.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
After that, on the second level, ZS pressed the 'β+β' button 44500000000 times, so the number becomes 10<sup class="upper-index">9</sup>β+β44500000000Β·2β=β9Β·10<sup class="upper-index">10</sup>. Then, ZS pressed the '<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/c77ded9b8209a8cb488cc2ec7b7fe1dae32a5309.png" style="max-width: 100.0%;max-height: 100.0%;"/>' button, levelling up and changing the number into <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/4c4d8829d987a7bcfd597cd1aa101327a66c0eca.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
Note that 300000 is a multiple of 3, so ZS the Coder can reach level 3. | [
{
"input": "3",
"output": "2\n17\n46"
},
{
"input": "2",
"output": "2\n17"
},
{
"input": "4",
"output": "2\n17\n46\n97"
},
{
"input": "1",
"output": "2"
},
{
"input": "100000",
"output": "2\n17\n46\n97\n176\n289\n442\n641\n892\n1201\n1574\n2017\n2536\n3137\n38... | 343 | 29,184,000 | 3 | 993 | |
672 | Summer Camp | [
"implementation"
] | null | null | Every year, hundreds of people come to summer camps, they learn new algorithms and solve hard problems.
This is your first year at summer camp, and you are asked to solve the following problem. All integers starting with 1 are written in one line. The prefix of these line is "123456789101112131415...". Your task is to print the *n*-th digit of this string (digits are numbered starting with 1. | The only line of the input contains a single integer *n* (1<=β€<=*n*<=β€<=1000)Β β the position of the digit you need to print. | Print the *n*-th digit of the line. | [
"3\n",
"11\n"
] | [
"3\n",
"0\n"
] | In the first sample the digit at position 3 is '3', as both integers 1 and 2 consist on one digit.
In the second sample, the digit at position 11 is '0', it belongs to the integer 10. | [
{
"input": "3",
"output": "3"
},
{
"input": "11",
"output": "0"
},
{
"input": "12",
"output": "1"
},
{
"input": "13",
"output": "1"
},
{
"input": "29",
"output": "9"
},
{
"input": "30",
"output": "2"
},
{
"input": "1000",
"output": "3"
... | 77 | 17,715,200 | 3 | 994 | |
813 | The Golden Age | [
"brute force",
"math"
] | null | null | Unlucky year in Berland is such a year that its number *n* can be represented as *n*<==<=*x**a*<=+<=*y**b*, where *a* and *b* are non-negative integer numbers.
For example, if *x*<==<=2 and *y*<==<=3 then the years 4 and 17 are unlucky (4<==<=20<=+<=31, 17<==<=23<=+<=32<==<=24<=+<=30) and year 18 isn't unlucky as there is no such representation for it.
Such interval of years that there are no unlucky years in it is called The Golden Age.
You should write a program which will find maximum length of The Golden Age which starts no earlier than the year *l* and ends no later than the year *r*. If all years in the interval [*l*,<=*r*] are unlucky then the answer is 0. | The first line contains four integer numbers *x*, *y*, *l* and *r* (2<=β€<=*x*,<=*y*<=β€<=1018, 1<=β€<=*l*<=β€<=*r*<=β€<=1018). | Print the maximum length of The Golden Age within the interval [*l*,<=*r*].
If all years in the interval [*l*,<=*r*] are unlucky then print 0. | [
"2 3 1 10\n",
"3 5 10 22\n",
"2 3 3 5\n"
] | [
"1\n",
"8\n",
"0\n"
] | In the first example the unlucky years are 2, 3, 4, 5, 7, 9 and 10. So maximum length of The Golden Age is achived in the intervals [1,β1], [6,β6] and [8,β8].
In the second example the longest Golden Age is the interval [15,β22]. | [
{
"input": "2 3 1 10",
"output": "1"
},
{
"input": "3 5 10 22",
"output": "8"
},
{
"input": "2 3 3 5",
"output": "0"
},
{
"input": "2 2 1 10",
"output": "1"
},
{
"input": "2 2 1 1000000",
"output": "213568"
},
{
"input": "2 2 1 1000000000000000000",
... | 31 | 0 | 0 | 996 | |
5 | Chat Servers Outgoing Traffic | [
"implementation"
] | A. Chat Server's Outgoing Traffic | 1 | 64 | Polycarp is working on a new project called "Polychat". Following modern tendencies in IT, he decided, that this project should contain chat as well. To achieve this goal, Polycarp has spent several hours in front of his laptop and implemented a chat server that can process three types of commands:
- Include a person to the chat ('Add' command). - Remove a person from the chat ('Remove' command). - Send a message from a person to all people, who are currently in the chat, including the one, who sends the message ('Send' command).
Now Polycarp wants to find out the amount of outgoing traffic that the server will produce while processing a particular set of commands.
Polycarp knows that chat server sends no traffic for 'Add' and 'Remove' commands. When 'Send' command is processed, server sends *l* bytes to each participant of the chat, where *l* is the length of the message.
As Polycarp has no time, he is asking for your help in solving this problem. | Input file will contain not more than 100 commands, each in its own line. No line will exceed 100 characters. Formats of the commands will be the following:
- +<name> for 'Add' command. - -<name> for 'Remove' command. - <sender_name>:<message_text> for 'Send' command.
<name> and <sender_name> is a non-empty sequence of Latin letters and digits. <message_text> can contain letters, digits and spaces, but can't start or end with a space. <message_text> can be an empty line.
It is guaranteed, that input data are correct, i.e. there will be no 'Add' command if person with such a name is already in the chat, there will be no 'Remove' command if there is no person with such a name in the chat etc.
All names are case-sensitive. | Print a single number β answer to the problem. | [
"+Mike\nMike:hello\n+Kate\n+Dmitry\n-Dmitry\nKate:hi\n-Kate\n",
"+Mike\n-Mike\n+Mike\nMike:Hi I am here\n-Mike\n+Kate\n-Kate\n"
] | [
"9\n",
"14\n"
] | none | [
{
"input": "+Mike\nMike:hello\n+Kate\n+Dmitry\n-Dmitry\nKate:hi\n-Kate",
"output": "9"
},
{
"input": "+Mike\n-Mike\n+Mike\nMike:Hi I am here\n-Mike\n+Kate\n-Kate",
"output": "14"
},
{
"input": "+Dmitry\n+Mike\nDmitry:All letters will be used\nDmitry:qwertyuiopasdfghjklzxcvbnm QWERTYUIO... | 248 | 0 | 3.876 | 1,001 |
449 | Jzzhu and Chocolate | [
"greedy",
"math"
] | null | null | Jzzhu has a big rectangular chocolate bar that consists of *n*<=Γ<=*m* unit squares. He wants to cut this bar exactly *k* times. Each cut must meet the following requirements:
- each cut should be straight (horizontal or vertical); - each cut should go along edges of unit squares (it is prohibited to divide any unit chocolate square with cut); - each cut should go inside the whole chocolate bar, and all cuts must be distinct.
The picture below shows a possible way to cut a 5<=Γ<=6 chocolate for 5 times.
Imagine Jzzhu have made *k* cuts and the big chocolate is splitted into several pieces. Consider the smallest (by area) piece of the chocolate, Jzzhu wants this piece to be as large as possible. What is the maximum possible area of smallest piece he can get with exactly *k* cuts? The area of a chocolate piece is the number of unit squares in it. | A single line contains three integers *n*,<=*m*,<=*k* (1<=β€<=*n*,<=*m*<=β€<=109;Β 1<=β€<=*k*<=β€<=2Β·109). | Output a single integer representing the answer. If it is impossible to cut the big chocolate *k* times, print -1. | [
"3 4 1\n",
"6 4 2\n",
"2 3 4\n"
] | [
"6\n",
"8\n",
"-1\n"
] | In the first sample, Jzzhu can cut the chocolate following the picture below:
In the second sample the optimal division looks like this:
In the third sample, it's impossible to cut a 2βΓβ3 chocolate 4 times. | [
{
"input": "3 4 1",
"output": "6"
},
{
"input": "6 4 2",
"output": "8"
},
{
"input": "2 3 4",
"output": "-1"
},
{
"input": "10 10 2",
"output": "30"
},
{
"input": "1000000000 1000000000 2000000000",
"output": "-1"
},
{
"input": "1000000000 1000000000 9... | 46 | 0 | 0 | 1,003 | |
451 | Game With Sticks | [
"implementation"
] | null | null | After winning gold and silver in IOI 2014, Akshat and Malvika want to have some fun. Now they are playing a game on a grid made of *n* horizontal and *m* vertical sticks.
An intersection point is any point on the grid which is formed by the intersection of one horizontal stick and one vertical stick.
In the grid shown below, *n*<==<=3 and *m*<==<=3. There are *n*<=+<=*m*<==<=6 sticks in total (horizontal sticks are shown in red and vertical sticks are shown in green). There are *n*Β·*m*<==<=9 intersection points, numbered from 1 to 9.
The rules of the game are very simple. The players move in turns. Akshat won gold, so he makes the first move. During his/her move, a player must choose any remaining intersection point and remove from the grid all sticks which pass through this point. A player will lose the game if he/she cannot make a move (i.e. there are no intersection points remaining on the grid at his/her move).
Assume that both players play optimally. Who will win the game? | The first line of input contains two space-separated integers, *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=100). | Print a single line containing "Akshat" or "Malvika" (without the quotes), depending on the winner of the game. | [
"2 2\n",
"2 3\n",
"3 3\n"
] | [
"Malvika\n",
"Malvika\n",
"Akshat\n"
] | Explanation of the first sample:
The grid has four intersection points, numbered from 1 to 4.
If Akshat chooses intersection point 1, then he will remove two sticks (1β-β2 and 1β-β3). The resulting grid will look like this.
Now there is only one remaining intersection point (i.e. 4). Malvika must choose it and remove both remaining sticks. After her move the grid will be empty.
In the empty grid, Akshat cannot make any move, hence he will lose.
Since all 4 intersection points of the grid are equivalent, Akshat will lose no matter which one he picks. | [
{
"input": "2 2",
"output": "Malvika"
},
{
"input": "2 3",
"output": "Malvika"
},
{
"input": "3 3",
"output": "Akshat"
},
{
"input": "20 68",
"output": "Malvika"
},
{
"input": "1 1",
"output": "Akshat"
},
{
"input": "1 2",
"output": "Akshat"
},
... | 31 | 0 | 3 | 1,005 | |
145 | Lucky Queries | [
"data structures"
] | null | null | Petya loves lucky numbers very much. Everybody knows that lucky numbers are positive integers whose decimal record contains only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.
Petya brought home string *s* with the length of *n*. The string only consists of lucky digits. The digits are numbered from the left to the right starting with 1. Now Petya should execute *m* queries of the following form:
- switch *l* *r* β "switch" digits (i.e. replace them with their opposites) at all positions with indexes from *l* to *r*, inclusive: each digit 4 is replaced with 7 and each digit 7 is replaced with 4 (1<=β€<=*l*<=β€<=*r*<=β€<=*n*); - count β find and print on the screen the length of the longest non-decreasing subsequence of string *s*.
Subsequence of a string *s* is a string that can be obtained from *s* by removing zero or more of its elements. A string is called non-decreasing if each successive digit is not less than the previous one.
Help Petya process the requests. | The first line contains two integers *n* and *m* (1<=β€<=*n*<=β€<=106,<=1<=β€<=*m*<=β€<=3Β·105) β the length of the string *s* and the number of queries correspondingly. The second line contains *n* lucky digits without spaces β Petya's initial string. Next *m* lines contain queries in the form described in the statement. | For each query count print an answer on a single line. | [
"2 3\n47\ncount\nswitch 1 2\ncount\n",
"3 5\n747\ncount\nswitch 1 1\ncount\nswitch 1 3\ncount\n"
] | [
"2\n1\n",
"2\n3\n2\n"
] | In the first sample the chronology of string *s* after some operations are fulfilled is as follows (the sought maximum subsequence is marked with bold):
1. 47 1. 74 1. 74 1. 747 1. 447 1. 447 1. 774 1. 774 | [] | 62 | 6,963,200 | -1 | 1,012 | |
202 | LLPS | [
"binary search",
"bitmasks",
"brute force",
"greedy",
"implementation",
"strings"
] | null | null | This problem's actual name, "Lexicographically Largest Palindromic Subsequence" is too long to fit into the page headline.
You are given string *s* consisting of lowercase English letters only. Find its lexicographically largest palindromic subsequence.
We'll call a non-empty string *s*[*p*1*p*2... *p**k*] = *s**p*1*s**p*2... *s**p**k* (1 <=β€<= *p*1<=<<=*p*2<=<<=...<=<<=*p**k* <=β€<= |*s*|) a subsequence of string *s* = *s*1*s*2... *s*|*s*|, where |*s*| is the length of string *s*. For example, strings "abcb", "b" and "abacaba" are subsequences of string "abacaba".
String *x* = *x*1*x*2... *x*|*x*| is lexicographically larger than string *y* = *y*1*y*2... *y*|*y*| if either |*x*| > |*y*| and *x*1<==<=*y*1, *x*2<==<=*y*2, ...,<=*x*|*y*|<==<=*y*|*y*|, or there exists such number *r* (*r*<=<<=|*x*|, *r*<=<<=|*y*|) that *x*1<==<=*y*1, *x*2<==<=*y*2, ..., *x**r*<==<=*y**r* and *x**r*<=<=+<=<=1<=><=*y**r*<=<=+<=<=1. Characters in the strings are compared according to their ASCII codes. For example, string "ranger" is lexicographically larger than string "racecar" and string "poster" is lexicographically larger than string "post".
String *s* = *s*1*s*2... *s*|*s*| is a palindrome if it matches string *rev*(*s*) = *s*|*s*|*s*|*s*|<=-<=1... *s*1. In other words, a string is a palindrome if it reads the same way from left to right and from right to left. For example, palindromic strings are "racecar", "refer" and "z". | The only input line contains a non-empty string *s* consisting of lowercase English letters only. Its length does not exceed 10. | Print the lexicographically largest palindromic subsequence of string *s*. | [
"radar\n",
"bowwowwow\n",
"codeforces\n",
"mississipp\n"
] | [
"rr\n",
"wwwww\n",
"s\n",
"ssss\n"
] | Among all distinct subsequences of string "radar" the following ones are palindromes: "a", "d", "r", "aa", "rr", "ada", "rar", "rdr", "raar" and "radar". The lexicographically largest of them is "rr". | [
{
"input": "radar",
"output": "rr"
},
{
"input": "bowwowwow",
"output": "wwwww"
},
{
"input": "codeforces",
"output": "s"
},
{
"input": "mississipp",
"output": "ssss"
},
{
"input": "tourist",
"output": "u"
},
{
"input": "romka",
"output": "r"
},
... | 92 | 6,656,000 | 0 | 1,015 | |
743 | Vladik and flights | [
"constructive algorithms",
"greedy",
"implementation"
] | null | null | Vladik is a competitive programmer. This year he is going to win the International Olympiad in Informatics. But it is not as easy as it sounds: the question Vladik face now is to find the cheapest way to get to the olympiad.
Vladik knows *n* airports. All the airports are located on a straight line. Each airport has unique id from 1 to *n*, Vladik's house is situated next to the airport with id *a*, and the place of the olympiad is situated next to the airport with id *b*. It is possible that Vladik's house and the place of the olympiad are located near the same airport.
To get to the olympiad, Vladik can fly between any pair of airports any number of times, but he has to start his route at the airport *a* and finish it at the airport *b*.
Each airport belongs to one of two companies. The cost of flight from the airport *i* to the airport *j* is zero if both airports belong to the same company, and |*i*<=-<=*j*| if they belong to different companies.
Print the minimum cost Vladik has to pay to get to the olympiad. | The first line contains three integers *n*, *a*, and *b* (1<=β€<=*n*<=β€<=105, 1<=β€<=*a*,<=*b*<=β€<=*n*)Β β the number of airports, the id of the airport from which Vladik starts his route and the id of the airport which he has to reach.
The second line contains a string with length *n*, which consists only of characters 0 and 1. If the *i*-th character in this string is 0, then *i*-th airport belongs to first company, otherwise it belongs to the second. | Print single integerΒ β the minimum cost Vladik has to pay to get to the olympiad. | [
"4 1 4\n1010\n",
"5 5 2\n10110\n"
] | [
"1",
"0"
] | In the first example Vladik can fly to the airport 2 at first and pay |1β-β2|β=β1 (because the airports belong to different companies), and then fly from the airport 2 to the airport 4 for free (because the airports belong to the same company). So the cost of the whole flight is equal to 1. It's impossible to get to the olympiad for free, so the answer is equal to 1.
In the second example Vladik can fly directly from the airport 5 to the airport 2, because they belong to the same company. | [
{
"input": "4 1 4\n1010",
"output": "1"
},
{
"input": "5 5 2\n10110",
"output": "0"
},
{
"input": "10 9 5\n1011111001",
"output": "1"
},
{
"input": "7 3 7\n1110111",
"output": "0"
},
{
"input": "1 1 1\n1",
"output": "0"
},
{
"input": "10 3 3\n100101101... | 30 | 4,608,000 | -1 | 1,018 | |
259 | Little Elephant and Chess | [
"brute force",
"strings"
] | null | null | The Little Elephant loves chess very much.
One day the Little Elephant and his friend decided to play chess. They've got the chess pieces but the board is a problem. They've got an 8<=Γ<=8 checkered board, each square is painted either black or white. The Little Elephant and his friend know that a proper chessboard doesn't have any side-adjacent cells with the same color and the upper left cell is white. To play chess, they want to make the board they have a proper chessboard. For that the friends can choose any row of the board and cyclically shift the cells of the chosen row, that is, put the last (rightmost) square on the first place in the row and shift the others one position to the right. You can run the described operation multiple times (or not run it at all).
For example, if the first line of the board looks like that "BBBBBBWW" (the white cells of the line are marked with character "W", the black cells are marked with character "B"), then after one cyclic shift it will look like that "WBBBBBBW".
Help the Little Elephant and his friend to find out whether they can use any number of the described operations to turn the board they have into a proper chessboard. | The input consists of exactly eight lines. Each line contains exactly eight characters "W" or "B" without any spaces: the *j*-th character in the *i*-th line stands for the color of the *j*-th cell of the *i*-th row of the elephants' board. Character "W" stands for the white color, character "B" stands for the black color.
Consider the rows of the board numbered from 1 to 8 from top to bottom, and the columns β from 1 to 8 from left to right. The given board can initially be a proper chessboard. | In a single line print "YES" (without the quotes), if we can make the board a proper chessboard and "NO" (without the quotes) otherwise. | [
"WBWBWBWB\nBWBWBWBW\nBWBWBWBW\nBWBWBWBW\nWBWBWBWB\nWBWBWBWB\nBWBWBWBW\nWBWBWBWB\n",
"WBWBWBWB\nWBWBWBWB\nBBWBWWWB\nBWBWBWBW\nBWBWBWBW\nBWBWBWWW\nBWBWBWBW\nBWBWBWBW\n"
] | [
"YES\n",
"NO\n"
] | In the first sample you should shift the following lines one position to the right: the 3-rd, the 6-th, the 7-th and the 8-th.
In the second sample there is no way you can achieve the goal. | [
{
"input": "WBWBWBWB\nBWBWBWBW\nBWBWBWBW\nBWBWBWBW\nWBWBWBWB\nWBWBWBWB\nBWBWBWBW\nWBWBWBWB",
"output": "YES"
},
{
"input": "WBWBWBWB\nWBWBWBWB\nBBWBWWWB\nBWBWBWBW\nBWBWBWBW\nBWBWBWWW\nBWBWBWBW\nBWBWBWBW",
"output": "NO"
},
{
"input": "BWBWBWBW\nWBWBWBWB\nBWBWBWBW\nBWBWBWBW\nWBWBWBWB\nWBW... | 92 | 0 | 3 | 1,019 | |
920 | Tea Queue | [
"implementation"
] | null | null | Recently *n* students from city S moved to city P to attend a programming camp.
They moved there by train. In the evening, all students in the train decided that they want to drink some tea. Of course, no two people can use the same teapot simultaneously, so the students had to form a queue to get their tea.
*i*-th student comes to the end of the queue at the beginning of *l**i*-th second. If there are multiple students coming to the queue in the same moment, then the student with greater index comes after the student with lesser index. Students in the queue behave as follows: if there is nobody in the queue before the student, then he uses the teapot for exactly one second and leaves the queue with his tea; otherwise the student waits for the people before him to get their tea. If at the beginning of *r**i*-th second student *i* still cannot get his tea (there is someone before him in the queue), then he leaves the queue without getting any tea.
For each student determine the second he will use the teapot and get his tea (if he actually gets it). | The first line contains one integer *t* β the number of test cases to solve (1<=β€<=*t*<=β€<=1000).
Then *t* test cases follow. The first line of each test case contains one integer *n* (1<=β€<=*n*<=β€<=1000) β the number of students.
Then *n* lines follow. Each line contains two integer *l**i*, *r**i* (1<=β€<=*l**i*<=β€<=*r**i*<=β€<=5000) β the second *i*-th student comes to the end of the queue, and the second he leaves the queue if he still cannot get his tea.
It is guaranteed that for every condition *l**i*<=-<=1<=β€<=*l**i* holds.
The sum of *n* over all test cases doesn't exceed 1000.
Note that in hacks you have to set *t*<==<=1. | For each test case print *n* integers. *i*-th of them must be equal to the second when *i*-th student gets his tea, or 0 if he leaves without tea. | [
"2\n2\n1 3\n1 4\n3\n1 5\n1 1\n2 3\n"
] | [
"1 2 \n1 0 2 \n"
] | The example contains 2 tests:
1. During 1-st second, students 1 and 2 come to the queue, and student 1 gets his tea. Student 2 gets his tea during 2-nd second. 1. During 1-st second, students 1 and 2 come to the queue, student 1 gets his tea, and student 2 leaves without tea. During 2-nd second, student 3 comes and gets his tea. | [
{
"input": "2\n2\n1 3\n1 4\n3\n1 5\n1 1\n2 3",
"output": "1 2 \n1 0 2 "
},
{
"input": "19\n1\n1 1\n1\n1 2\n1\n1 1000\n1\n1 2000\n1\n2 2\n1\n2 3\n1\n2 1000\n1\n2 2000\n1\n1999 1999\n1\n1999 2000\n1\n2000 2000\n2\n1 1\n1 1\n2\n1 1\n1 2\n2\n1 2\n1 1\n2\n1 2000\n1 1\n2\n1 1\n1 2000\n2\n1 2000\n2 2\n2\n2... | 46 | 5,632,000 | 0 | 1,022 | |
488 | Giga Tower | [
"brute force"
] | null | null | Giga Tower is the tallest and deepest building in Cyberland. There are 17<=777<=777<=777 floors, numbered from <=-<=8<=888<=888<=888 to 8<=888<=888<=888. In particular, there is floor 0 between floor <=-<=1 and floor 1. Every day, thousands of tourists come to this place to enjoy the wonderful view.
In Cyberland, it is believed that the number "8" is a lucky number (that's why Giga Tower has 8<=888<=888<=888 floors above the ground), and, an integer is lucky, if and only if its decimal notation contains at least one digit "8". For example, 8,<=<=-<=180,<=808 are all lucky while 42,<=<=-<=10 are not. In the Giga Tower, if you write code at a floor with lucky floor number, good luck will always be with you (Well, this round is #278, also lucky, huh?).
Tourist Henry goes to the tower to seek good luck. Now he is at the floor numbered *a*. He wants to find the minimum positive integer *b*, such that, if he walks *b* floors higher, he will arrive at a floor with a lucky number. | The only line of input contains an integer *a* (<=-<=109<=β€<=*a*<=β€<=109). | Print the minimum *b* in a line. | [
"179\n",
"-1\n",
"18\n"
] | [
"1\n",
"9\n",
"10\n"
] | For the first sample, he has to arrive at the floor numbered 180.
For the second sample, he will arrive at 8.
Note that *b* should be positive, so the answer for the third sample is 10, not 0. | [
{
"input": "179",
"output": "1"
},
{
"input": "-1",
"output": "9"
},
{
"input": "18",
"output": "10"
},
{
"input": "-410058385",
"output": "1"
},
{
"input": "-586825624",
"output": "1"
},
{
"input": "852318890",
"output": "1"
},
{
"input": ... | 124 | 0 | 0 | 1,023 | |
902 | Coloring a Tree | [
"dfs and similar",
"dsu",
"greedy"
] | null | null | You are given a rooted tree with *n* vertices. The vertices are numbered from 1 to *n*, the root is the vertex number 1.
Each vertex has a color, let's denote the color of vertex *v* by *c**v*. Initially *c**v*<==<=0.
You have to color the tree into the given colors using the smallest possible number of steps. On each step you can choose a vertex *v* and a color *x*, and then color all vectices in the subtree of *v* (including *v* itself) in color *x*. In other words, for every vertex *u*, such that the path from root to *u* passes through *v*, set *c**u*<==<=*x*.
It is guaranteed that you have to color each vertex in a color different from 0.
You can learn what a rooted tree is using the link: [https://en.wikipedia.org/wiki/Tree_(graph_theory)](https://en.wikipedia.org/wiki/Tree_(graph_theory)). | The first line contains a single integer *n* (2<=β€<=*n*<=β€<=104)Β β the number of vertices in the tree.
The second line contains *n*<=-<=1 integers *p*2,<=*p*3,<=...,<=*p**n* (1<=β€<=*p**i*<=<<=*i*), where *p**i* means that there is an edge between vertices *i* and *p**i*.
The third line contains *n* integers *c*1,<=*c*2,<=...,<=*c**n* (1<=β€<=*c**i*<=β€<=*n*), where *c**i* is the color you should color the *i*-th vertex into.
It is guaranteed that the given graph is a tree. | Print a single integerΒ β the minimum number of steps you have to perform to color the tree into given colors. | [
"6\n1 2 2 1 5\n2 1 1 1 1 1\n",
"7\n1 1 2 3 1 4\n3 3 1 1 1 2 3\n"
] | [
"3\n",
"5\n"
] | The tree from the first sample is shown on the picture (numbers are vetices' indices):
<img class="tex-graphics" src="https://espresso.codeforces.com/10324ccdc37f95343acc4f3c6050d8c334334ffa.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On first step we color all vertices in the subtree of vertex 1 into color 2 (numbers are colors):
<img class="tex-graphics" src="https://espresso.codeforces.com/1c7bb267e2c1a006132248a43121400189309e2f.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On seond step we color all vertices in the subtree of vertex 5 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/2201a6d49b89ba850ff0d0bdcbb3f8e9dd3871a8.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On third step we color all vertices in the subtree of vertex 2 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/6fa977fcdebdde94c47695151e0427b33d0102c5.png" style="max-width: 100.0%;max-height: 100.0%;"/>
The tree from the second sample is shown on the picture (numbers are vetices' indices):
<img class="tex-graphics" src="https://espresso.codeforces.com/d70f9ae72a2ed429dd6531cac757e375dd3c953d.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On first step we color all vertices in the subtree of vertex 1 into color 3 (numbers are colors):
<img class="tex-graphics" src="https://espresso.codeforces.com/7289e8895d0dd56c47b6b17969b9cf77b36786b5.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On second step we color all vertices in the subtree of vertex 3 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/819001df7229138db3a407713744d1e3be88b64e.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On third step we color all vertices in the subtree of vertex 6 into color 2:
<img class="tex-graphics" src="https://espresso.codeforces.com/80ebbd870a0a339636a21b9acdaf9de046458b43.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On fourth step we color all vertices in the subtree of vertex 4 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/ed836aa723ac0176abde4e32988e3ac205014e93.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On fith step we color all vertices in the subtree of vertex 7 into color 3:
<img class="tex-graphics" src="https://espresso.codeforces.com/8132909e11b41c27b8df2f0b0c10bc841f35e58a.png" style="max-width: 100.0%;max-height: 100.0%;"/> | [
{
"input": "6\n1 2 2 1 5\n2 1 1 1 1 1",
"output": "3"
},
{
"input": "7\n1 1 2 3 1 4\n3 3 1 1 1 2 3",
"output": "5"
},
{
"input": "2\n1\n2 2",
"output": "1"
},
{
"input": "3\n1 1\n2 2 2",
"output": "1"
},
{
"input": "4\n1 2 1\n1 2 3 4",
"output": "4"
},
{
... | 873 | 6,758,400 | 3 | 1,024 | |
495 | Modular Equations | [
"math",
"number theory"
] | null | null | Last week, Hamed learned about a new type of equations in his math class called Modular Equations. Lets define *i* modulo *j* as the remainder of division of *i* by *j* and denote it by . A Modular Equation, as Hamed's teacher described, is an equation of the form in which *a* and *b* are two non-negative integers and *x* is a variable. We call a positive integer *x* for which a solution of our equation.
Hamed didn't pay much attention to the class since he was watching a movie. He only managed to understand the definitions of these equations.
Now he wants to write his math exercises but since he has no idea how to do that, he asked you for help. He has told you all he knows about Modular Equations and asked you to write a program which given two numbers *a* and *b* determines how many answers the Modular Equation has. | In the only line of the input two space-separated integers *a* and *b* (0<=β€<=*a*,<=*b*<=β€<=109) are given. | If there is an infinite number of answers to our equation, print "infinity" (without the quotes). Otherwise print the number of solutions of the Modular Equation . | [
"21 5\n",
"9435152 272\n",
"10 10\n"
] | [
"2\n",
"282\n",
"infinity\n"
] | In the first sample the answers of the Modular Equation are 8 and 16 since <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/6f5ff39ebd209bf990adaf91f4b82f9687097224.png" style="max-width: 100.0%;max-height: 100.0%;"/> | [
{
"input": "21 5",
"output": "2"
},
{
"input": "9435152 272",
"output": "282"
},
{
"input": "10 10",
"output": "infinity"
},
{
"input": "0 1000000000",
"output": "0"
},
{
"input": "11 2",
"output": "2"
},
{
"input": "1 0",
"output": "1"
},
{
... | 124 | 0 | 3 | 1,025 | |
412 | Pattern | [
"implementation",
"strings"
] | null | null | Developers often face with regular expression patterns. A pattern is usually defined as a string consisting of characters and metacharacters that sets the rules for your search. These patterns are most often used to check whether a particular string meets the certain rules.
In this task, a pattern will be a string consisting of small English letters and question marks ('?'). The question mark in the pattern is a metacharacter that denotes an arbitrary small letter of the English alphabet. We will assume that a string matches the pattern if we can transform the string into the pattern by replacing the question marks by the appropriate characters. For example, string aba matches patterns: ???, ??a, a?a, aba.
Programmers that work for the R1 company love puzzling each other (and themselves) with riddles. One of them is as follows: you are given *n* patterns of the same length, you need to find a pattern that contains as few question marks as possible, and intersects with each of the given patterns. Two patterns intersect if there is a string that matches both the first and the second pattern. Can you solve this riddle? | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=105) β the number of patterns. Next *n* lines contain the patterns.
It is guaranteed that the patterns can only consist of small English letters and symbols '?'. All patterns are non-empty and have the same length. The total length of all the patterns does not exceed 105 characters. | In a single line print the answer to the problem β the pattern with the minimal number of signs '?', which intersects with each of the given ones. If there are several answers, print any of them. | [
"2\n?ab\n??b\n",
"2\na\nb\n",
"1\n?a?b\n"
] | [
"xab\n",
"?\n",
"cacb\n"
] | Consider the first example. Pattern xab intersects with each of the given patterns. Pattern ??? also intersects with each of the given patterns, but it contains more question signs, hence it is not an optimal answer. Clearly, xab is the optimal answer, because it doesn't contain any question sign. There are a lot of other optimal answers, for example: aab, bab, cab, dab and so on. | [
{
"input": "2\n?ab\n??b",
"output": "xab"
},
{
"input": "2\na\nb",
"output": "?"
},
{
"input": "1\n?a?b",
"output": "cacb"
},
{
"input": "1\n?",
"output": "x"
},
{
"input": "3\nabacaba\nabacaba\nabacaba",
"output": "abacaba"
},
{
"input": "3\nabc?t\n?b... | 61 | 5,632,000 | 0 | 1,027 | |
401 | Vanya and Cards | [
"implementation",
"math"
] | null | null | Vanya loves playing. He even has a special set of cards to play with. Each card has a single integer. The number on the card can be positive, negative and can even be equal to zero. The only limit is, the number on each card doesn't exceed *x* in the absolute value.
Natasha doesn't like when Vanya spends a long time playing, so she hid all of his cards. Vanya became sad and started looking for the cards but he only found *n* of them. Vanya loves the balance, so he wants the sum of all numbers on found cards equal to zero. On the other hand, he got very tired of looking for cards. Help the boy and say what is the minimum number of cards does he need to find to make the sum equal to zero?
You can assume that initially Vanya had infinitely many cards with each integer number from <=-<=*x* to *x*. | The first line contains two integers: *n* (1<=β€<=*n*<=β€<=1000) β the number of found cards and *x* (1<=β€<=*x*<=β€<=1000) β the maximum absolute value of the number on a card. The second line contains *n* space-separated integers β the numbers on found cards. It is guaranteed that the numbers do not exceed *x* in their absolute value. | Print a single number β the answer to the problem. | [
"3 2\n-1 1 2\n",
"2 3\n-2 -2\n"
] | [
"1\n",
"2\n"
] | In the first sample, Vanya needs to find a single card with number -2.
In the second sample, Vanya needs to find two cards with number 2. He can't find a single card with the required number as the numbers on the lost cards do not exceed 3 in their absolute value. | [
{
"input": "3 2\n-1 1 2",
"output": "1"
},
{
"input": "2 3\n-2 -2",
"output": "2"
},
{
"input": "4 4\n1 2 3 4",
"output": "3"
},
{
"input": "2 2\n-1 -1",
"output": "1"
},
{
"input": "15 5\n-2 -1 2 -4 -3 4 -4 -2 -2 2 -2 -1 1 -4 -2",
"output": "4"
},
{
"... | 46 | 0 | 3 | 1,029 | |
152 | Marks | [
"implementation"
] | null | null | Vasya, or Mr. Vasily Petrov is a dean of a department in a local university. After the winter exams he got his hands on a group's gradebook.
Overall the group has *n* students. They received marks for *m* subjects. Each student got a mark from 1 to 9 (inclusive) for each subject.
Let's consider a student the best at some subject, if there is no student who got a higher mark for this subject. Let's consider a student successful, if there exists a subject he is the best at.
Your task is to find the number of successful students in the group. | The first input line contains two integers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=100) β the number of students and the number of subjects, correspondingly. Next *n* lines each containing *m* characters describe the gradebook. Each character in the gradebook is a number from 1 to 9. Note that the marks in a rows are not sepatated by spaces. | Print the single number β the number of successful students in the given group. | [
"3 3\n223\n232\n112\n",
"3 5\n91728\n11828\n11111\n"
] | [
"2\n",
"3\n"
] | In the first sample test the student number 1 is the best at subjects 1 and 3, student 2 is the best at subjects 1 and 2, but student 3 isn't the best at any subject.
In the second sample test each student is the best at at least one subject. | [
{
"input": "3 3\n223\n232\n112",
"output": "2"
},
{
"input": "3 5\n91728\n11828\n11111",
"output": "3"
},
{
"input": "2 2\n48\n27",
"output": "1"
},
{
"input": "2 1\n4\n6",
"output": "1"
},
{
"input": "1 2\n57",
"output": "1"
},
{
"input": "1 1\n5",
... | 124 | 0 | 0 | 1,030 | |
753 | Santa Claus and Candies | [
"dp",
"greedy",
"math"
] | null | null | Santa Claus has *n* candies, he dreams to give them as gifts to children.
What is the maximal number of children for whose he can give candies if Santa Claus want each kid should get distinct positive integer number of candies. Santa Class wants to give all *n* candies he has. | The only line contains positive integer number *n* (1<=β€<=*n*<=β€<=1000) β number of candies Santa Claus has. | Print to the first line integer number *k* β maximal number of kids which can get candies.
Print to the second line *k* distinct integer numbers: number of candies for each of *k* kid. The sum of *k* printed numbers should be exactly *n*.
If there are many solutions, print any of them. | [
"5\n",
"9\n",
"2\n"
] | [
"2\n2 3\n",
"3\n3 5 1\n",
"1\n2 \n"
] | none | [
{
"input": "5",
"output": "2\n1 4 "
},
{
"input": "9",
"output": "3\n1 2 6 "
},
{
"input": "2",
"output": "1\n2 "
},
{
"input": "1",
"output": "1\n1 "
},
{
"input": "3",
"output": "2\n1 2 "
},
{
"input": "1000",
"output": "44\n1 2 3 4 5 6 7 8 9 10 ... | 124 | 0 | 3 | 1,037 | |
697 | Pineapple Incident | [
"implementation",
"math"
] | null | null | Ted has a pineapple. This pineapple is able to bark like a bulldog! At time *t* (in seconds) it barks for the first time. Then every *s* seconds after it, it barks twice with 1 second interval. Thus it barks at times *t*, *t*<=+<=*s*, *t*<=+<=*s*<=+<=1, *t*<=+<=2*s*, *t*<=+<=2*s*<=+<=1, etc.
Barney woke up in the morning and wants to eat the pineapple, but he can't eat it when it's barking. Barney plans to eat it at time *x* (in seconds), so he asked you to tell him if it's gonna bark at that time. | The first and only line of input contains three integers *t*, *s* and *x* (0<=β€<=*t*,<=*x*<=β€<=109, 2<=β€<=*s*<=β€<=109)Β β the time the pineapple barks for the first time, the pineapple barking interval, and the time Barney wants to eat the pineapple respectively. | Print a single "YES" (without quotes) if the pineapple will bark at time *x* or a single "NO" (without quotes) otherwise in the only line of output. | [
"3 10 4\n",
"3 10 3\n",
"3 8 51\n",
"3 8 52\n"
] | [
"NO\n",
"YES\n",
"YES\n",
"YES\n"
] | In the first and the second sample cases pineapple will bark at moments 3, 13, 14, ..., so it won't bark at the moment 4 and will bark at the moment 3.
In the third and fourth sample cases pineapple will bark at moments 3, 11, 12, 19, 20, 27, 28, 35, 36, 43, 44, 51, 52, 59, ..., so it will bark at both moments 51 and 52. | [
{
"input": "3 10 4",
"output": "NO"
},
{
"input": "3 10 3",
"output": "YES"
},
{
"input": "3 8 51",
"output": "YES"
},
{
"input": "3 8 52",
"output": "YES"
},
{
"input": "456947336 740144 45",
"output": "NO"
},
{
"input": "33 232603 599417964",
"ou... | 46 | 0 | 0 | 1,039 | |
658 | Bear and Reverse Radewoosh | [
"implementation"
] | null | null | Limak and Radewoosh are going to compete against each other in the upcoming algorithmic contest. They are equally skilled but they won't solve problems in the same order.
There will be *n* problems. The *i*-th problem has initial score *p**i* and it takes exactly *t**i* minutes to solve it. Problems are sorted by difficultyΒ β it's guaranteed that *p**i*<=<<=*p**i*<=+<=1 and *t**i*<=<<=*t**i*<=+<=1.
A constant *c* is given too, representing the speed of loosing points. Then, submitting the *i*-th problem at time *x* (*x* minutes after the start of the contest) gives *max*(0,<= *p**i*<=-<=*c*Β·*x*) points.
Limak is going to solve problems in order 1,<=2,<=...,<=*n* (sorted increasingly by *p**i*). Radewoosh is going to solve them in order *n*,<=*n*<=-<=1,<=...,<=1 (sorted decreasingly by *p**i*). Your task is to predict the outcomeΒ β print the name of the winner (person who gets more points at the end) or a word "Tie" in case of a tie.
You may assume that the duration of the competition is greater or equal than the sum of all *t**i*. That means both Limak and Radewoosh will accept all *n* problems. | The first line contains two integers *n* and *c* (1<=β€<=*n*<=β€<=50,<=1<=β€<=*c*<=β€<=1000)Β β the number of problems and the constant representing the speed of loosing points.
The second line contains *n* integers *p*1,<=*p*2,<=...,<=*p**n* (1<=β€<=*p**i*<=β€<=1000,<=*p**i*<=<<=*p**i*<=+<=1)Β β initial scores.
The third line contains *n* integers *t*1,<=*t*2,<=...,<=*t**n* (1<=β€<=*t**i*<=β€<=1000,<=*t**i*<=<<=*t**i*<=+<=1) where *t**i* denotes the number of minutes one needs to solve the *i*-th problem. | Print "Limak" (without quotes) if Limak will get more points in total. Print "Radewoosh" (without quotes) if Radewoosh will get more points in total. Print "Tie" (without quotes) if Limak and Radewoosh will get the same total number of points. | [
"3 2\n50 85 250\n10 15 25\n",
"3 6\n50 85 250\n10 15 25\n",
"8 1\n10 20 30 40 50 60 70 80\n8 10 58 63 71 72 75 76\n"
] | [
"Limak\n",
"Radewoosh\n",
"Tie\n"
] | In the first sample, there are 3 problems. Limak solves them as follows:
1. Limak spends 10 minutes on the 1-st problem and he gets 50β-β*c*Β·10β=β50β-β2Β·10β=β30 points. 1. Limak spends 15 minutes on the 2-nd problem so he submits it 10β+β15β=β25 minutes after the start of the contest. For the 2-nd problem he gets 85β-β2Β·25β=β35 points. 1. He spends 25 minutes on the 3-rd problem so he submits it 10β+β15β+β25β=β50 minutes after the start. For this problem he gets 250β-β2Β·50β=β150 points.
So, Limak got 30β+β35β+β150β=β215 points.
Radewoosh solves problem in the reversed order:
1. Radewoosh solves 3-rd problem after 25 minutes so he gets 250β-β2Β·25β=β200 points. 1. He spends 15 minutes on the 2-nd problem so he submits it 25β+β15β=β40 minutes after the start. He gets 85β-β2Β·40β=β5 points for this problem. 1. He spends 10 minutes on the 1-st problem so he submits it 25β+β15β+β10β=β50 minutes after the start. He gets *max*(0,β50β-β2Β·50)β=β*max*(0,ββ-β50)β=β0 points.
Radewoosh got 200β+β5β+β0β=β205 points in total. Limak has 215 points so Limak wins.
In the second sample, Limak will get 0 points for each problem and Radewoosh will first solve the hardest problem and he will get 250β-β6Β·25β=β100 points for that. Radewoosh will get 0 points for other two problems but he is the winner anyway.
In the third sample, Limak will get 2 points for the 1-st problem and 2 points for the 2-nd problem. Radewoosh will get 4 points for the 8-th problem. They won't get points for other problems and thus there is a tie because 2β+β2β=β4. | [
{
"input": "3 2\n50 85 250\n10 15 25",
"output": "Limak"
},
{
"input": "3 6\n50 85 250\n10 15 25",
"output": "Radewoosh"
},
{
"input": "8 1\n10 20 30 40 50 60 70 80\n8 10 58 63 71 72 75 76",
"output": "Tie"
},
{
"input": "4 1\n3 5 6 9\n1 2 4 8",
"output": "Limak"
},
{... | 93 | 0 | 0 | 1,040 | |
965 | Single-use Stones | [
"binary search",
"flows",
"greedy",
"two pointers"
] | null | null | A lot of frogs want to cross a river. A river is $w$ units width, but frogs can only jump $l$ units long, where $l < w$. Frogs can also jump on lengths shorter than $l$. but can't jump longer. Hopefully, there are some stones in the river to help them.
The stones are located at integer distances from the banks. There are $a_i$ stones at the distance of $i$ units from the bank the frogs are currently at. Each stone can only be used once by one frog, after that it drowns in the water.
What is the maximum number of frogs that can cross the river, given that then can only jump on the stones? | The first line contains two integers $w$ and $l$ ($1 \le l < w \le 10^5$)Β β the width of the river and the maximum length of a frog's jump.
The second line contains $w - 1$ integers $a_1, a_2, \ldots, a_{w-1}$ ($0 \le a_i \le 10^4$), where $a_i$ is the number of stones at the distance $i$ from the bank the frogs are currently at. | Print a single integerΒ β the maximum number of frogs that can cross the river. | [
"10 5\n0 0 1 0 2 0 0 1 0\n",
"10 3\n1 1 1 1 2 1 1 1 1\n"
] | [
"3\n",
"3\n"
] | In the first sample two frogs can use the different stones at the distance $5$, and one frog can use the stones at the distances $3$ and then $8$.
In the second sample although there are two stones at the distance $5$, that does not help. The three paths are: $0 \to 3 \to 6 \to 9 \to 10$, $0 \to 2 \to 5 \to 8 \to 10$, $0 \to 1 \to 4 \to 7 \to 10$. | [
{
"input": "10 5\n0 0 1 0 2 0 0 1 0",
"output": "3"
},
{
"input": "10 3\n1 1 1 1 2 1 1 1 1",
"output": "3"
},
{
"input": "2 1\n0",
"output": "0"
},
{
"input": "2 1\n5",
"output": "5"
},
{
"input": "10 4\n0 0 6 2 7 1 6 4 0",
"output": "8"
},
{
"input": ... | 78 | 21,401,600 | 0 | 1,042 | |
701 | Cards | [
"greedy",
"implementation"
] | null | null | There are *n* cards (*n* is even) in the deck. Each card has a positive integer written on it. *n*<=/<=2 people will play new card game. At the beginning of the game each player gets two cards, each card is given to exactly one player.
Find the way to distribute cards such that the sum of values written of the cards will be equal for each player. It is guaranteed that it is always possible. | The first line of the input contains integer *n* (2<=β€<=*n*<=β€<=100)Β β the number of cards in the deck. It is guaranteed that *n* is even.
The second line contains the sequence of *n* positive integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=100), where *a**i* is equal to the number written on the *i*-th card. | Print *n*<=/<=2 pairs of integers, the *i*-th pair denote the cards that should be given to the *i*-th player. Each card should be given to exactly one player. Cards are numbered in the order they appear in the input.
It is guaranteed that solution exists. If there are several correct answers, you are allowed to print any of them. | [
"6\n1 5 7 4 4 3\n",
"4\n10 10 10 10\n"
] | [
"1 3\n6 2\n4 5\n",
"1 2\n3 4\n"
] | In the first sample, cards are distributed in such a way that each player has the sum of numbers written on his cards equal to 8.
In the second sample, all values *a*<sub class="lower-index">*i*</sub> are equal. Thus, any distribution is acceptable. | [
{
"input": "6\n1 5 7 4 4 3",
"output": "1 3\n6 2\n4 5"
},
{
"input": "4\n10 10 10 10",
"output": "1 4\n2 3"
},
{
"input": "100\n2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 ... | 93 | 0 | 0 | 1,044 | |
643 | Bear and Two Paths | [
"constructive algorithms",
"graphs"
] | null | null | Bearland has *n* cities, numbered 1 through *n*. Cities are connected via bidirectional roads. Each road connects two distinct cities. No two roads connect the same pair of cities.
Bear Limak was once in a city *a* and he wanted to go to a city *b*. There was no direct connection so he decided to take a long walk, visiting each city exactly once. Formally:
- There is no road between *a* and *b*. - There exists a sequence (path) of *n* distinct cities *v*1,<=*v*2,<=...,<=*v**n* that *v*1<==<=*a*, *v**n*<==<=*b* and there is a road between *v**i* and *v**i*<=+<=1 for .
On the other day, the similar thing happened. Limak wanted to travel between a city *c* and a city *d*. There is no road between them but there exists a sequence of *n* distinct cities *u*1,<=*u*2,<=...,<=*u**n* that *u*1<==<=*c*, *u**n*<==<=*d* and there is a road between *u**i* and *u**i*<=+<=1 for .
Also, Limak thinks that there are at most *k* roads in Bearland. He wonders whether he remembers everything correctly.
Given *n*, *k* and four distinct cities *a*, *b*, *c*, *d*, can you find possible paths (*v*1,<=...,<=*v**n*) and (*u*1,<=...,<=*u**n*) to satisfy all the given conditions? Find any solution or print -1 if it's impossible. | The first line of the input contains two integers *n* and *k* (4<=β€<=*n*<=β€<=1000, *n*<=-<=1<=β€<=*k*<=β€<=2*n*<=-<=2)Β β the number of cities and the maximum allowed number of roads, respectively.
The second line contains four distinct integers *a*, *b*, *c* and *d* (1<=β€<=*a*,<=*b*,<=*c*,<=*d*<=β€<=*n*). | Print -1 if it's impossible to satisfy all the given conditions. Otherwise, print two lines with paths descriptions. The first of these two lines should contain *n* distinct integers *v*1,<=*v*2,<=...,<=*v**n* where *v*1<==<=*a* and *v**n*<==<=*b*. The second line should contain *n* distinct integers *u*1,<=*u*2,<=...,<=*u**n* where *u*1<==<=*c* and *u**n*<==<=*d*.
Two paths generate at most 2*n*<=-<=2 roads: (*v*1,<=*v*2),<=(*v*2,<=*v*3),<=...,<=(*v**n*<=-<=1,<=*v**n*),<=(*u*1,<=*u*2),<=(*u*2,<=*u*3),<=...,<=(*u**n*<=-<=1,<=*u**n*). Your answer will be considered wrong if contains more than *k* distinct roads or any other condition breaks. Note that (*x*,<=*y*) and (*y*,<=*x*) are the same road. | [
"7 11\n2 4 7 3\n",
"1000 999\n10 20 30 40\n"
] | [
"2 7 1 3 6 5 4\n7 1 5 4 6 2 3\n",
"-1\n"
] | In the first sample test, there should be 7 cities and at most 11 roads. The provided sample solution generates 10 roads, as in the drawing. You can also see a simple path of length *n* between 2 and 4, and a path between 7 and 3. | [
{
"input": "7 11\n2 4 7 3",
"output": "2 7 1 3 6 5 4\n7 1 5 4 6 2 3"
},
{
"input": "1000 999\n10 20 30 40",
"output": "-1"
},
{
"input": "4 4\n1 2 3 4",
"output": "-1"
},
{
"input": "5 6\n5 2 4 1",
"output": "5 4 3 1 2\n4 5 3 2 1"
},
{
"input": "57 88\n54 30 5 43"... | 62 | 6,963,200 | 3 | 1,048 | |
125 | Simple XML | [
"implementation"
] | null | null | Let's define a string <x> as an opening tag, where *x* is any small letter of the Latin alphabet. Each opening tag matches a closing tag of the type </x>, where *x* is the same letter.
Tegs can be nested into each other: in this case one opening and closing tag pair is located inside another pair.
Let's define the notion of a XML-text:
- an empty string is a XML-text - if *s* is a XML-text, then *s*'=<a>+*s*+</a> also is a XML-text, where *a* is any small Latin letter - if *s*1, *s*2 are XML-texts, then *s*1+*s*2 also is a XML-text
You are given a XML-text (it is guaranteed that the text is valid), your task is to print in the following form:
- each tag (opening and closing) is located on a single line - print before the tag 2<=*<=*h* spaces, where *h* is the level of the tag's nestedness. | The input data consists on the only non-empty string β the XML-text, its length does not exceed 1000 characters. It is guaranteed that the text is valid. The text contains no spaces. | Print the given XML-text according to the above-given rules. | [
"<a><b><c></c></b></a>\n",
"<a><b></b><d><c></c></d></a>\n"
] | [
"<a>\n <b>\n <c>\n </c>\n </b>\n</a>\n",
"<a>\n <b>\n </b>\n <d>\n <c>\n </c>\n </d>\n</a>\n"
] | none | [
{
"input": "<a><b><c></c></b></a>",
"output": "<a>\n <b>\n <c>\n </c>\n </b>\n</a>"
},
{
"input": "<a><b></b><d><c></c></d></a>",
"output": "<a>\n <b>\n </b>\n <d>\n <c>\n </c>\n </d>\n</a>"
},
{
"input": "<z></z>",
"output": "<z>\n</z>"
},
{
"input": "<u><d... | 186 | 0 | 0 | 1,049 | |
287 | IQ Test | [
"brute force",
"implementation"
] | null | null | In the city of Ultima Thule job applicants are often offered an IQ test.
The test is as follows: the person gets a piece of squared paper with a 4<=Γ<=4 square painted on it. Some of the square's cells are painted black and others are painted white. Your task is to repaint at most one cell the other color so that the picture has a 2<=Γ<=2 square, completely consisting of cells of the same color. If the initial picture already has such a square, the person should just say so and the test will be completed.
Your task is to write a program that determines whether it is possible to pass the test. You cannot pass the test if either repainting any cell or no action doesn't result in a 2<=Γ<=2 square, consisting of cells of the same color. | Four lines contain four characters each: the *j*-th character of the *i*-th line equals "." if the cell in the *i*-th row and the *j*-th column of the square is painted white, and "#", if the cell is black. | Print "YES" (without the quotes), if the test can be passed and "NO" (without the quotes) otherwise. | [
"####\n.#..\n####\n....\n",
"####\n....\n####\n....\n"
] | [
"YES\n",
"NO\n"
] | In the first test sample it is enough to repaint the first cell in the second row. After such repainting the required 2βΓβ2 square is on the intersection of the 1-st and 2-nd row with the 1-st and 2-nd column. | [
{
"input": "###.\n...#\n###.\n...#",
"output": "NO"
},
{
"input": ".##.\n#..#\n.##.\n#..#",
"output": "NO"
},
{
"input": ".#.#\n#.#.\n.#.#\n#.#.",
"output": "NO"
},
{
"input": "##..\n..##\n##..\n..##",
"output": "NO"
},
{
"input": "#.#.\n#.#.\n.#.#\n.#.#",
"ou... | 46 | 6,963,200 | 0 | 1,050 | |
292 | Network Topology | [
"graphs",
"implementation"
] | null | null | This problem uses a simplified network topology model, please read the problem statement carefully and use it as a formal document as you develop the solution.
Polycarpus continues working as a system administrator in a large corporation. The computer network of this corporation consists of *n* computers, some of them are connected by a cable. The computers are indexed by integers from 1 to *n*. It's known that any two computers connected by cable directly or through other computers
Polycarpus decided to find out the network's topology. A network topology is the way of describing the network configuration, the scheme that shows the location and the connections of network devices.
Polycarpus knows three main network topologies: bus, ring and star. A bus is the topology that represents a shared cable with all computers connected with it. In the ring topology the cable connects each computer only with two other ones. A star is the topology where all computers of a network are connected to the single central node.
Let's represent each of these network topologies as a connected non-directed graph. A bus is a connected graph that is the only path, that is, the graph where all nodes are connected with two other ones except for some two nodes that are the beginning and the end of the path. A ring is a connected graph, where all nodes are connected with two other ones. A star is a connected graph, where a single central node is singled out and connected with all other nodes. For clarifications, see the picture.
You've got a connected non-directed graph that characterizes the computer network in Polycarpus' corporation. Help him find out, which topology type the given network is. If that is impossible to do, say that the network's topology is unknown. | The first line contains two space-separated integers *n* and *m* (4<=β€<=*n*<=β€<=105;Β 3<=β€<=*m*<=β€<=105) β the number of nodes and edges in the graph, correspondingly. Next *m* lines contain the description of the graph's edges. The *i*-th line contains a space-separated pair of integers *x**i*, *y**i* (1<=β€<=*x**i*,<=*y**i*<=β€<=*n*) β the numbers of nodes that are connected by the *i*-the edge.
It is guaranteed that the given graph is connected. There is at most one edge between any two nodes. No edge connects a node with itself. | In a single line print the network topology name of the given graph. If the answer is the bus, print "bus topology" (without the quotes), if the answer is the ring, print "ring topology" (without the quotes), if the answer is the star, print "star topology" (without the quotes). If no answer fits, print "unknown topology" (without the quotes). | [
"4 3\n1 2\n2 3\n3 4\n",
"4 4\n1 2\n2 3\n3 4\n4 1\n",
"4 3\n1 2\n1 3\n1 4\n",
"4 4\n1 2\n2 3\n3 1\n1 4\n"
] | [
"bus topology\n",
"ring topology\n",
"star topology\n",
"unknown topology\n"
] | none | [
{
"input": "4 3\n1 2\n2 3\n3 4",
"output": "bus topology"
},
{
"input": "4 4\n1 2\n2 3\n3 4\n4 1",
"output": "ring topology"
},
{
"input": "4 3\n1 2\n1 3\n1 4",
"output": "star topology"
},
{
"input": "4 4\n1 2\n2 3\n3 1\n1 4",
"output": "unknown topology"
},
{
"i... | 1,902 | 15,155,200 | 3 | 1,052 | |
543 | Destroying Roads | [
"constructive algorithms",
"graphs",
"shortest paths"
] | null | null | In some country there are exactly *n* cities and *m* bidirectional roads connecting the cities. Cities are numbered with integers from 1 to *n*. If cities *a* and *b* are connected by a road, then in an hour you can go along this road either from city *a* to city *b*, or from city *b* to city *a*. The road network is such that from any city you can get to any other one by moving along the roads.
You want to destroy the largest possible number of roads in the country so that the remaining roads would allow you to get from city *s*1 to city *t*1 in at most *l*1 hours and get from city *s*2 to city *t*2 in at most *l*2 hours.
Determine what maximum number of roads you need to destroy in order to meet the condition of your plan. If it is impossible to reach the desired result, print -1. | The first line contains two integers *n*, *m* (1<=β€<=*n*<=β€<=3000, )Β β the number of cities and roads in the country, respectively.
Next *m* lines contain the descriptions of the roads as pairs of integers *a**i*, *b**i* (1<=β€<=*a**i*,<=*b**i*<=β€<=*n*, *a**i*<=β <=*b**i*). It is guaranteed that the roads that are given in the description can transport you from any city to any other one. It is guaranteed that each pair of cities has at most one road between them.
The last two lines contains three integers each, *s*1, *t*1, *l*1 and *s*2, *t*2, *l*2, respectively (1<=β€<=*s**i*,<=*t**i*<=β€<=*n*, 0<=β€<=*l**i*<=β€<=*n*). | Print a single number β the answer to the problem. If the it is impossible to meet the conditions, print -1. | [
"5 4\n1 2\n2 3\n3 4\n4 5\n1 3 2\n3 5 2\n",
"5 4\n1 2\n2 3\n3 4\n4 5\n1 3 2\n2 4 2\n",
"5 4\n1 2\n2 3\n3 4\n4 5\n1 3 2\n3 5 1\n"
] | [
"0\n",
"1\n",
"-1\n"
] | none | [
{
"input": "5 4\n1 2\n2 3\n3 4\n4 5\n1 3 2\n3 5 2",
"output": "0"
},
{
"input": "5 4\n1 2\n2 3\n3 4\n4 5\n1 3 2\n2 4 2",
"output": "1"
},
{
"input": "5 4\n1 2\n2 3\n3 4\n4 5\n1 3 2\n3 5 1",
"output": "-1"
},
{
"input": "9 9\n1 2\n2 3\n2 4\n4 5\n5 7\n5 6\n3 8\n8 9\n9 6\n1 7 4\... | 77 | 819,200 | 0 | 1,053 | |
467 | George and Accommodation | [
"implementation"
] | null | null | George has recently entered the BSUCP (Berland State University for Cool Programmers). George has a friend Alex who has also entered the university. Now they are moving into a dormitory.
George and Alex want to live in the same room. The dormitory has *n* rooms in total. At the moment the *i*-th room has *p**i* people living in it and the room can accommodate *q**i* people in total (*p**i*<=β€<=*q**i*). Your task is to count how many rooms has free place for both George and Alex. | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=100) β the number of rooms.
The *i*-th of the next *n* lines contains two integers *p**i* and *q**i* (0<=β€<=*p**i*<=β€<=*q**i*<=β€<=100) β the number of people who already live in the *i*-th room and the room's capacity. | Print a single integer β the number of rooms where George and Alex can move in. | [
"3\n1 1\n2 2\n3 3\n",
"3\n1 10\n0 10\n10 10\n"
] | [
"0\n",
"2\n"
] | none | [
{
"input": "3\n1 1\n2 2\n3 3",
"output": "0"
},
{
"input": "3\n1 10\n0 10\n10 10",
"output": "2"
},
{
"input": "2\n36 67\n61 69",
"output": "2"
},
{
"input": "3\n21 71\n10 88\n43 62",
"output": "3"
},
{
"input": "3\n1 2\n2 3\n3 4",
"output": "0"
},
{
"... | 46 | 0 | 3 | 1,056 | |
980 | Links and Pearls | [
"implementation",
"math"
] | null | null | A necklace can be described as a string of links ('-') and pearls ('o'), with the last link or pearl connected to the first one.
You can remove a link or a pearl and insert it between two other existing links or pearls (or between a link and a pearl) on the necklace. This process can be repeated as many times as you like, but you can't throw away any parts.
Can you make the number of links between every two adjacent pearls equal? Two pearls are considered to be adjacent if there is no other pearl between them.
Note that the final necklace should remain as one circular part of the same length as the initial necklace. | The only line of input contains a string $s$ ($3 \leq |s| \leq 100$), representing the necklace, where a dash '-' represents a link and the lowercase English letter 'o' represents a pearl. | Print "YES" if the links and pearls can be rejoined such that the number of links between adjacent pearls is equal. Otherwise print "NO".
You can print each letter in any case (upper or lower). | [
"-o-o--",
"-o---\n",
"-o---o-\n",
"ooo\n"
] | [
"YES",
"YES",
"NO",
"YES\n"
] | none | [
{
"input": "-o-o--",
"output": "YES"
},
{
"input": "-o---",
"output": "YES"
},
{
"input": "-o---o-",
"output": "NO"
},
{
"input": "ooo",
"output": "YES"
},
{
"input": "---",
"output": "YES"
},
{
"input": "--o-o-----o----o--oo-o-----ooo-oo---o--",
"... | 93 | 0 | -1 | 1,059 | |
729 | Financiers Game | [
"dp"
] | null | null | This problem has unusual memory constraint.
At evening, Igor and Zhenya the financiers became boring, so they decided to play a game. They prepared *n* papers with the income of some company for some time periods. Note that the income can be positive, zero or negative.
Igor and Zhenya placed the papers in a row and decided to take turns making moves. Igor will take the papers from the left side, Zhenya will take the papers from the right side. Igor goes first and takes 1 or 2 (on his choice) papers from the left. Then, on each turn a player can take *k* or *k*<=+<=1 papers from his side if the opponent took exactly *k* papers in the previous turn. Players can't skip moves. The game ends when there are no papers left, or when some of the players can't make a move.
Your task is to determine the difference between the sum of incomes on the papers Igor took and the sum of incomes on the papers Zhenya took, assuming both players play optimally. Igor wants to maximize the difference, Zhenya wants to minimize it. | The first line contains single positive integer *n* (1<=β€<=*n*<=β€<=4000)Β β the number of papers.
The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (<=-<=105<=β€<=*a**i*<=β€<=105), where *a**i* is the income on the *i*-th paper from the left. | Print the difference between the sum of incomes on the papers Igor took and the sum of incomes on the papers Zhenya took, assuming both players play optimally. Igor wants to maximize the difference, Zhenya wants to minimize it. | [
"3\n1 3 1\n",
"5\n-1 -2 -1 -2 -1\n",
"4\n-4 -2 4 5\n"
] | [
"4\n",
"0\n",
"-13\n"
] | In the first example it's profitable for Igor to take two papers from the left to have the sum of the incomes equal to 4. Then Zhenya wouldn't be able to make a move since there would be only one paper, and he would be able to take only 2 or 3.. | [] | 93 | 512,000 | 0 | 1,062 | |
979 | Treasure Hunt | [
"greedy"
] | null | null | After the big birthday party, Katie still wanted Shiro to have some more fun. Later, she came up with a game called treasure hunt. Of course, she invited her best friends Kuro and Shiro to play with her.
The three friends are very smart so they passed all the challenges very quickly and finally reached the destination. But the treasure can only belong to one cat so they started to think of something which can determine who is worthy of the treasure. Instantly, Kuro came up with some ribbons.
A random colorful ribbon is given to each of the cats. Each color of the ribbon can be represented as an uppercase or lowercase Latin letter. Let's call a consecutive subsequence of colors that appears in the ribbon a subribbon. The beauty of a ribbon is defined as the maximum number of times one of its subribbon appears in the ribbon. The more the subribbon appears, the more beautiful is the ribbon. For example, the ribbon aaaaaaa has the beauty of $7$ because its subribbon a appears $7$ times, and the ribbon abcdabc has the beauty of $2$ because its subribbon abc appears twice.
The rules are simple. The game will have $n$ turns. Every turn, each of the cats must change strictly one color (at one position) in his/her ribbon to an arbitrary color which is different from the unchanged one. For example, a ribbon aaab can be changed into acab in one turn. The one having the most beautiful ribbon after $n$ turns wins the treasure.
Could you find out who is going to be the winner if they all play optimally? | The first line contains an integer $n$ ($0 \leq n \leq 10^{9}$)Β β the number of turns.
Next 3 lines contain 3 ribbons of Kuro, Shiro and Katie one per line, respectively. Each ribbon is a string which contains no more than $10^{5}$ uppercase and lowercase Latin letters and is not empty. It is guaranteed that the length of all ribbons are equal for the purpose of fairness. Note that uppercase and lowercase letters are considered different colors. | Print the name of the winner ("Kuro", "Shiro" or "Katie"). If there are at least two cats that share the maximum beauty, print "Draw". | [
"3\nKuroo\nShiro\nKatie\n",
"7\ntreasurehunt\nthreefriends\nhiCodeforces\n",
"1\nabcabc\ncbabac\nababca\n",
"15\nfoPaErcvJ\nmZaxowpbt\nmkuOlaHRE\n"
] | [
"Kuro\n",
"Shiro\n",
"Katie\n",
"Draw\n"
] | In the first example, after $3$ turns, Kuro can change his ribbon into ooooo, which has the beauty of $5$, while reaching such beauty for Shiro and Katie is impossible (both Shiro and Katie can reach the beauty of at most $4$, for example by changing Shiro's ribbon into SSiSS and changing Katie's ribbon into Kaaaa). Therefore, the winner is Kuro.
In the fourth example, since the length of each of the string is $9$ and the number of turn is $15$, everyone can change their ribbons in some way to reach the maximal beauty of $9$ by changing their strings into zzzzzzzzz after 9 turns, and repeatedly change their strings into azzzzzzzz and then into zzzzzzzzz thrice. Therefore, the game ends in a draw. | [
{
"input": "3\nKuroo\nShiro\nKatie",
"output": "Kuro"
},
{
"input": "7\ntreasurehunt\nthreefriends\nhiCodeforces",
"output": "Shiro"
},
{
"input": "1\nabcabc\ncbabac\nababca",
"output": "Katie"
},
{
"input": "15\nfoPaErcvJ\nmZaxowpbt\nmkuOlaHRE",
"output": "Draw"
},
{... | 93 | 307,200 | 0 | 1,065 | |
888 | K-Dominant Character | [
"binary search",
"implementation",
"two pointers"
] | null | null | You are given a string *s* consisting of lowercase Latin letters. Character *c* is called *k*-dominant iff each substring of *s* with length at least *k* contains this character *c*.
You have to find minimum *k* such that there exists at least one *k*-dominant character. | The first line contains string *s* consisting of lowercase Latin letters (1<=β€<=|*s*|<=β€<=100000). | Print one number β the minimum value of *k* such that there exists at least one *k*-dominant character. | [
"abacaba\n",
"zzzzz\n",
"abcde\n"
] | [
"2\n",
"1\n",
"3\n"
] | none | [
{
"input": "abacaba",
"output": "2"
},
{
"input": "zzzzz",
"output": "1"
},
{
"input": "abcde",
"output": "3"
},
{
"input": "bcaccacaaabaacaabaaabcbbcbcaacacbcbaaaacccacbbcbaabcbacaacbabacacacaccbbccbcbacbbbbccccabcabaaab",
"output": "8"
},
{
"input": "daabcdabbab... | 93 | 204,800 | 3 | 1,066 | |
916 | Jamie and Alarm Snooze | [
"brute force",
"implementation",
"math"
] | null | null | Jamie loves sleeping. One day, he decides that he needs to wake up at exactly *hh*:<=*mm*. However, he hates waking up, so he wants to make waking up less painful by setting the alarm at a lucky time. He will then press the snooze button every *x* minutes until *hh*:<=*mm* is reached, and only then he will wake up. He wants to know what is the smallest number of times he needs to press the snooze button.
A time is considered lucky if it contains a digit '7'. For example, 13:<=07 and 17:<=27 are lucky, while 00:<=48 and 21:<=34 are not lucky.
Note that it is not necessary that the time set for the alarm and the wake-up time are on the same day. It is guaranteed that there is a lucky time Jamie can set so that he can wake at *hh*:<=*mm*.
Formally, find the smallest possible non-negative integer *y* such that the time representation of the time *x*Β·*y* minutes before *hh*:<=*mm* contains the digit '7'.
Jamie uses 24-hours clock, so after 23:<=59 comes 00:<=00. | The first line contains a single integer *x* (1<=β€<=*x*<=β€<=60).
The second line contains two two-digit integers, *hh* and *mm* (00<=β€<=*hh*<=β€<=23,<=00<=β€<=*mm*<=β€<=59). | Print the minimum number of times he needs to press the button. | [
"3\n11 23\n",
"5\n01 07\n"
] | [
"2\n",
"0\n"
] | In the first sample, Jamie needs to wake up at 11:23. So, he can set his alarm at 11:17. He would press the snooze button when the alarm rings at 11:17 and at 11:20.
In the second sample, Jamie can set his alarm at exactly at 01:07 which is lucky. | [
{
"input": "3\n11 23",
"output": "2"
},
{
"input": "5\n01 07",
"output": "0"
},
{
"input": "34\n09 24",
"output": "3"
},
{
"input": "2\n14 37",
"output": "0"
},
{
"input": "14\n19 54",
"output": "9"
},
{
"input": "42\n15 44",
"output": "12"
},
... | 46 | 5,632,000 | -1 | 1,070 | |
343 | Rational Resistance | [
"math",
"number theory"
] | null | null | Mad scientist Mike is building a time machine in his spare time. To finish the work, he needs a resistor with a certain resistance value.
However, all Mike has is lots of identical resistors with unit resistance *R*0<==<=1. Elements with other resistance can be constructed from these resistors. In this problem, we will consider the following as elements:
1. one resistor; 1. an element and one resistor plugged in sequence; 1. an element and one resistor plugged in parallel.
With the consecutive connection the resistance of the new element equals *R*<==<=*R**e*<=+<=*R*0. With the parallel connection the resistance of the new element equals . In this case *R**e* equals the resistance of the element being connected.
Mike needs to assemble an element with a resistance equal to the fraction . Determine the smallest possible number of resistors he needs to make such an element. | The single input line contains two space-separated integers *a* and *b* (1<=β€<=*a*,<=*b*<=β€<=1018). It is guaranteed that the fraction is irreducible. It is guaranteed that a solution always exists. | Print a single number β the answer to the problem.
Please do not use the %lld specifier to read or write 64-bit integers in Π‘++. It is recommended to use the cin, cout streams or the %I64d specifier. | [
"1 1\n",
"3 2\n",
"199 200\n"
] | [
"1\n",
"3\n",
"200\n"
] | In the first sample, one resistor is enough.
In the second sample one can connect the resistors in parallel, take the resulting element and connect it to a third resistor consecutively. Then, we get an element with resistance <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/5305da389756aab6423d918a08ced468f05604df.png" style="max-width: 100.0%;max-height: 100.0%;"/>. We cannot make this element using two resistors. | [
{
"input": "1 1",
"output": "1"
},
{
"input": "3 2",
"output": "3"
},
{
"input": "199 200",
"output": "200"
},
{
"input": "1 1000000000000000000",
"output": "1000000000000000000"
},
{
"input": "3 1",
"output": "3"
},
{
"input": "21 8",
"output": "7... | 92 | 0 | 3 | 1,075 | |
152 | Pocket Book | [
"combinatorics"
] | null | null | One day little Vasya found mom's pocket book. The book had *n* names of her friends and unusually enough, each name was exactly *m* letters long. Let's number the names from 1 to *n* in the order in which they are written.
As mom wasn't home, Vasya decided to play with names: he chose three integers *i*, *j*, *k* (1<=β€<=*i*<=<<=*j*<=β€<=*n*, 1<=β€<=*k*<=β€<=*m*), then he took names number *i* and *j* and swapped their prefixes of length *k*. For example, if we take names "CBDAD" and "AABRD" and swap their prefixes with the length of 3, the result will be names "AABAD" and "CBDRD".
You wonder how many different names Vasya can write instead of name number 1, if Vasya is allowed to perform any number of the described actions. As Vasya performs each action, he chooses numbers *i*, *j*, *k* independently from the previous moves and his choice is based entirely on his will. The sought number can be very large, so you should only find it modulo 1000000007 (109<=+<=7). | The first input line contains two integers *n* and *m* (1<=β€<=*n*,<=*m*<=β€<=100) β the number of names and the length of each name, correspondingly. Then *n* lines contain names, each name consists of exactly *m* uppercase Latin letters. | Print the single number β the number of different names that could end up in position number 1 in the pocket book after the applying the procedures described above. Print the number modulo 1000000007 (109<=+<=7). | [
"2 3\nAAB\nBAA\n",
"4 5\nABABA\nBCGDG\nAAAAA\nYABSA\n"
] | [
"4\n",
"216\n"
] | In the first sample Vasya can get the following names in the position number 1: "AAB", "AAA", "BAA" and "BAB". | [
{
"input": "2 3\nAAB\nBAA",
"output": "4"
},
{
"input": "4 5\nABABA\nBCGDG\nAAAAA\nYABSA",
"output": "216"
},
{
"input": "1 1\nE",
"output": "1"
},
{
"input": "2 2\nNS\nPD",
"output": "4"
},
{
"input": "3 4\nPJKD\nNFJX\nFGFK",
"output": "81"
},
{
"inpu... | 92 | 0 | 3 | 1,079 | |
926 | Large Bouquets | [] | null | null | A flower shop has got *n* bouquets, and the *i*-th bouquet consists of *a**i* flowers. Vasya, the manager of the shop, decided to make large bouquets from these bouquets.
Vasya thinks that a bouquet is large if it is made of two or more initial bouquets, and there is a constraint: the total number of flowers in a large bouquet should be odd. Each of the initial bouquets can be a part of at most one large bouquet. If an initial bouquet becomes a part of a large bouquet, all its flowers are included in the large bouquet.
Determine the maximum possible number of large bouquets Vasya can make. | The first line contains a single positive integer *n* (1<=β€<=*n*<=β€<=105) β the number of initial bouquets.
The second line contains a sequence of integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=106) β the number of flowers in each of the initial bouquets. | Print the maximum number of large bouquets Vasya can make. | [
"5\n2 3 4 2 7\n",
"6\n2 2 6 8 6 12\n",
"3\n11 4 10\n"
] | [
"2\n",
"0\n",
"1\n"
] | In the first example Vasya can make 2 large bouquets. For example, the first bouquet can contain the first and the fifth initial bouquets (the total number of flowers is then equal to 9), and the second bouquet can consist of the second and the third initial bouquets (the total number of flowers is then equal to 7). The fourth initial bouquet is unused in this scheme.
In the second example it is not possible to form a single bouquet with odd number of flowers.
In the third example Vasya can make one large bouquet. For example, he can make it using all three initial bouquets. The size of the large bouquet is then equal to 11β+β4β+β10β=β25. | [
{
"input": "5\n2 3 4 2 7",
"output": "2"
},
{
"input": "6\n2 2 6 8 6 12",
"output": "0"
},
{
"input": "3\n11 4 10",
"output": "1"
},
{
"input": "1\n1",
"output": "0"
},
{
"input": "1\n2",
"output": "0"
},
{
"input": "1\n999999",
"output": "0"
},
... | 46 | 0 | 0 | 1,084 | |
172 | Phone Code | [
"*special",
"brute force",
"implementation"
] | null | null | Polycarpus has *n* friends in Tarasov city. Polycarpus knows phone numbers of all his friends: they are strings *s*1,<=*s*2,<=...,<=*s**n*. All these strings consist only of digits and have the same length.
Once Polycarpus needed to figure out Tarasov city phone code. He assumed that the phone code of the city is the longest common prefix of all phone numbers of his friends. In other words, it is the longest string *c* which is a prefix (the beginning) of each *s**i* for all *i* (1<=β€<=*i*<=β€<=*n*). Help Polycarpus determine the length of the city phone code. | The first line of the input contains an integer *n* (2<=β€<=*n*<=β€<=3Β·104) β the number of Polycarpus's friends. The following *n* lines contain strings *s*1,<=*s*2,<=...,<=*s**n* β the phone numbers of Polycarpus's friends. It is guaranteed that all strings consist only of digits and have the same length from 1 to 20, inclusive. It is also guaranteed that all strings are different. | Print the number of digits in the city phone code. | [
"4\n00209\n00219\n00999\n00909\n",
"2\n1\n2\n",
"3\n77012345678999999999\n77012345678901234567\n77012345678998765432\n"
] | [
"2\n",
"0\n",
"12\n"
] | A prefix of string *t* is a string that is obtained by deleting zero or more digits from the end of string *t*. For example, string "00209" has 6 prefixes: "" (an empty prefix), "0", "00", "002", "0020", "00209".
In the first sample the city phone code is string "00".
In the second sample the city phone code is an empty string.
In the third sample the city phone code is string "770123456789". | [
{
"input": "4\n00209\n00219\n00999\n00909",
"output": "2"
},
{
"input": "2\n1\n2",
"output": "0"
},
{
"input": "3\n77012345678999999999\n77012345678901234567\n77012345678998765432",
"output": "12"
},
{
"input": "5\n4491183345\n4491184811\n4491162340\n4491233399\n4491449214",
... | 404 | 6,451,200 | 3 | 1,086 | |
2 | The least round way | [
"dp",
"math"
] | B. The least round way | 2 | 64 | There is a square matrix *n*<=Γ<=*n*, consisting of non-negative integer numbers. You should find such a way on it that
- starts in the upper left cell of the matrix; - each following cell is to the right or down from the current cell; - the way ends in the bottom right cell.
Moreover, if we multiply together all the numbers along the way, the result should be the least "round". In other words, it should end in the least possible number of zeros. | The first line contains an integer number *n* (2<=β€<=*n*<=β€<=1000), *n* is the size of the matrix. Then follow *n* lines containing the matrix elements (non-negative integer numbers not exceeding 109). | In the first line print the least number of trailing zeros. In the second line print the correspondent way itself. | [
"3\n1 2 3\n4 5 6\n7 8 9\n"
] | [
"0\nDDRR\n"
] | none | [
{
"input": "3\n1 2 3\n4 5 6\n7 8 9",
"output": "0\nDDRR"
},
{
"input": "2\n7 6\n3 8",
"output": "0\nDR"
},
{
"input": "3\n4 10 5\n10 9 4\n6 5 3",
"output": "1\nDRRD"
},
{
"input": "4\n1 1 9 9\n3 4 7 3\n7 9 1 7\n1 7 1 5",
"output": "0\nDDDRRR"
},
{
"input": "5\n8 3... | 2,000 | 0 | 0 | 1,087 |
912 | New Year's Eve | [
"bitmasks",
"constructive algorithms",
"number theory"
] | null | null | Since Grisha behaved well last year, at New Year's Eve he was visited by Ded Moroz who brought an enormous bag of gifts with him! The bag contains *n* sweet candies from the good ol' bakery, each labeled from 1 to *n* corresponding to its tastiness. No two candies have the same tastiness.
The choice of candies has a direct effect on Grisha's happiness. One can assume that he should take the tastiest onesΒ β but no, the holiday magic turns things upside down. It is the xor-sum of tastinesses that matters, not the ordinary sum!
A xor-sum of a sequence of integers *a*1,<=*a*2,<=...,<=*a**m* is defined as the bitwise XOR of all its elements: , here denotes the bitwise XOR operation; more about bitwise XOR can be found [here.](https://en.wikipedia.org/wiki/Bitwise_operation#XOR)
Ded Moroz warned Grisha he has more houses to visit, so Grisha can take no more than *k* candies from the bag. Help Grisha determine the largest xor-sum (largest xor-sum means maximum happiness!) he can obtain. | The sole string contains two integers *n* and *k* (1<=β€<=*k*<=β€<=*n*<=β€<=1018). | Output one numberΒ β the largest possible xor-sum. | [
"4 3\n",
"6 6\n"
] | [
"7\n",
"7\n"
] | In the first sample case, one optimal answer is 1, 2 and 4, giving the xor-sum of 7.
In the second sample case, one can, for example, take all six candies and obtain the xor-sum of 7. | [
{
"input": "4 3",
"output": "7"
},
{
"input": "6 6",
"output": "7"
},
{
"input": "2 2",
"output": "3"
},
{
"input": "1022 10",
"output": "1023"
},
{
"input": "415853337373441 52",
"output": "562949953421311"
},
{
"input": "75 12",
"output": "127"
... | 1,000 | 5,632,000 | 0 | 1,088 | |
224 | Array | [
"bitmasks",
"implementation",
"two pointers"
] | null | null | You've got an array *a*, consisting of *n* integers: *a*1,<=*a*2,<=...,<=*a**n*. Your task is to find a minimal by inclusion segment [*l*,<=*r*] (1<=β€<=*l*<=β€<=*r*<=β€<=*n*) such, that among numbers *a**l*,<=Β *a**l*<=+<=1,<=Β ...,<=Β *a**r* there are exactly *k* distinct numbers.
Segment [*l*,<=*r*] (1<=β€<=*l*<=β€<=*r*<=β€<=*n*; *l*,<=*r* are integers) of length *m*<==<=*r*<=-<=*l*<=+<=1, satisfying the given property, is called minimal by inclusion, if there is no segment [*x*,<=*y*] satisfying the property and less then *m* in length, such that 1<=β€<=*l*<=β€<=*x*<=β€<=*y*<=β€<=*r*<=β€<=*n*. Note that the segment [*l*,<=*r*] doesn't have to be minimal in length among all segments, satisfying the given property. | The first line contains two space-separated integers: *n* and *k* (1<=β€<=*n*,<=*k*<=β€<=105). The second line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n*Β β elements of the array *a* (1<=β€<=*a**i*<=β€<=105). | Print a space-separated pair of integers *l* and *r* (1<=β€<=*l*<=β€<=*r*<=β€<=*n*) such, that the segment [*l*,<=*r*] is the answer to the problem. If the sought segment does not exist, print "-1 -1" without the quotes. If there are multiple correct answers, print any of them. | [
"4 2\n1 2 2 3\n",
"8 3\n1 1 2 2 3 3 4 5\n",
"7 4\n4 7 7 4 7 4 7\n"
] | [
"1 2\n",
"2 5\n",
"-1 -1\n"
] | In the first sample among numbers *a*<sub class="lower-index">1</sub> and *a*<sub class="lower-index">2</sub> there are exactly two distinct numbers.
In the second sample segment [2,β5] is a minimal by inclusion segment with three distinct numbers, but it is not minimal in length among such segments.
In the third sample there is no segment with four distinct numbers. | [
{
"input": "4 2\n1 2 2 3",
"output": "1 2"
},
{
"input": "8 3\n1 1 2 2 3 3 4 5",
"output": "2 5"
},
{
"input": "7 4\n4 7 7 4 7 4 7",
"output": "-1 -1"
},
{
"input": "5 1\n1 7 2 3 2",
"output": "1 1"
},
{
"input": "1 2\n666",
"output": "-1 -1"
},
{
"inp... | 186 | 307,200 | 0 | 1,089 | |
834 | The Useless Toy | [
"implementation"
] | null | null | Walking through the streets of Marshmallow City, Slastyona have spotted some merchants selling a kind of useless toy which is very popular nowadaysΒ β caramel spinner! Wanting to join the craze, she has immediately bought the strange contraption.
Spinners in Sweetland have the form of V-shaped pieces of caramel. Each spinner can, well, spin around an invisible magic axis. At a specific point in time, a spinner can take 4 positions shown below (each one rotated 90 degrees relative to the previous, with the fourth one followed by the first one):
After the spinner was spun, it starts its rotation, which is described by a following algorithm: the spinner maintains its position for a second then majestically switches to the next position in clockwise or counter-clockwise order, depending on the direction the spinner was spun in.
Slastyona managed to have spinner rotating for exactly *n* seconds. Being fascinated by elegance of the process, she completely forgot the direction the spinner was spun in! Lucky for her, she managed to recall the starting position, and wants to deduct the direction given the information she knows. Help her do this. | There are two characters in the first stringΒ β the starting and the ending position of a spinner. The position is encoded with one of the following characters: v (ASCII code 118, lowercase v), < (ASCII code 60), ^ (ASCII code 94) or > (ASCII code 62) (see the picture above for reference). Characters are separated by a single space.
In the second strings, a single number *n* is given (0<=β€<=*n*<=β€<=109)Β β the duration of the rotation.
It is guaranteed that the ending position of a spinner is a result of a *n* second spin in any of the directions, assuming the given starting position. | Output cw, if the direction is clockwise, ccwΒ β if counter-clockwise, and undefined otherwise. | [
"^ >\n1\n",
"< ^\n3\n",
"^ v\n6\n"
] | [
"cw\n",
"ccw\n",
"undefined\n"
] | none | [
{
"input": "^ >\n1",
"output": "cw"
},
{
"input": "< ^\n3",
"output": "ccw"
},
{
"input": "^ v\n6",
"output": "undefined"
},
{
"input": "^ >\n999999999",
"output": "ccw"
},
{
"input": "> v\n1",
"output": "cw"
},
{
"input": "v <\n1",
"output": "cw"
... | 46 | 4,608,000 | -1 | 1,094 | |
566 | Clique in the Divisibility Graph | [
"dp",
"math",
"number theory"
] | null | null | As you must know, the maximum clique problem in an arbitrary graph is *NP*-hard. Nevertheless, for some graphs of specific kinds it can be solved effectively.
Just in case, let us remind you that a clique in a non-directed graph is a subset of the vertices of a graph, such that any two vertices of this subset are connected by an edge. In particular, an empty set of vertexes and a set consisting of a single vertex, are cliques.
Let's define a divisibility graph for a set of positive integers *A*<==<={*a*1,<=*a*2,<=...,<=*a**n*} as follows. The vertices of the given graph are numbers from set *A*, and two numbers *a**i* and *a**j* (*i*<=β <=*j*) are connected by an edge if and only if either *a**i* is divisible by *a**j*, or *a**j* is divisible by *a**i*.
You are given a set of non-negative integers *A*. Determine the size of a maximum clique in a divisibility graph for set *A*. | The first line contains integer *n* (1<=β€<=*n*<=β€<=106), that sets the size of set *A*.
The second line contains *n* distinct positive integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=106) β elements of subset *A*. The numbers in the line follow in the ascending order. | Print a single number β the maximum size of a clique in a divisibility graph for set *A*. | [
"8\n3 4 6 8 10 18 21 24\n"
] | [
"3\n"
] | In the first sample test a clique of size 3 is, for example, a subset of vertexes {3,β6,β18}. A clique of a larger size doesn't exist in this graph. | [
{
"input": "8\n3 4 6 8 10 18 21 24",
"output": "3"
},
{
"input": "5\n2 3 4 8 16",
"output": "4"
},
{
"input": "2\n10 20",
"output": "2"
},
{
"input": "2\n10 21",
"output": "1"
},
{
"input": "5\n250000 333333 500000 666666 1000000",
"output": "3"
},
{
"... | 1,000 | 102,502,400 | 0 | 1,099 | |
940 | Alena And The Heater | [
"binary search",
"implementation"
] | null | null | "We've tried solitary confinement, waterboarding and listening to Just In Beaver, to no avail. We need something extreme."
"Little Alena got an array as a birthday present..."
The array *b* of length *n* is obtained from the array *a* of length *n* and two integers *l* and *r*Β (*l*<=β€<=*r*) using the following procedure:
*b*1<==<=*b*2<==<=*b*3<==<=*b*4<==<=0.
For all 5<=β€<=*i*<=β€<=*n*:
- *b**i*<==<=0 if *a**i*,<=*a**i*<=-<=1,<=*a**i*<=-<=2,<=*a**i*<=-<=3,<=*a**i*<=-<=4<=><=*r* and *b**i*<=-<=1<==<=*b**i*<=-<=2<==<=*b**i*<=-<=3<==<=*b**i*<=-<=4<==<=1 - *b**i*<==<=1 if *a**i*,<=*a**i*<=-<=1,<=*a**i*<=-<=2,<=*a**i*<=-<=3,<=*a**i*<=-<=4<=<<=*l* and *b**i*<=-<=1<==<=*b**i*<=-<=2<==<=*b**i*<=-<=3<==<=*b**i*<=-<=4<==<=0 - *b**i*<==<=*b**i*<=-<=1 otherwise
You are given arrays *a* and *b*' of the same length. Find two integers *l* and *r*Β (*l*<=β€<=*r*), such that applying the algorithm described above will yield an array *b* equal to *b*'.
It's guaranteed that the answer exists. | The first line of input contains a single integer *n* (5<=β€<=*n*<=β€<=105)Β β the length of *a* and *b*'.
The second line of input contains *n* space separated integers *a*1,<=...,<=*a**n* (<=-<=109<=β€<=*a**i*<=β€<=109)Β β the elements of *a*.
The third line of input contains a string of *n* characters, consisting of 0 and 1Β β the elements of *b*'. Note that they are not separated by spaces. | Output two integers *l* and *r*Β (<=-<=109<=β€<=*l*<=β€<=*r*<=β€<=109), conforming to the requirements described above.
If there are multiple solutions, output any of them.
It's guaranteed that the answer exists. | [
"5\n1 2 3 4 5\n00001\n",
"10\n-10 -9 -8 -7 -6 6 7 8 9 10\n0000111110\n"
] | [
"6 15\n",
"-5 5\n"
] | In the first test case any pair of *l* and *r* pair is valid, if 6ββ€β*l*ββ€β*r*ββ€β10<sup class="upper-index">9</sup>, in that case *b*<sub class="lower-index">5</sub>β=β1, because *a*<sub class="lower-index">1</sub>,β...,β*a*<sub class="lower-index">5</sub>β<β*l*. | [
{
"input": "5\n1 2 3 4 5\n00001",
"output": "6 1000000000"
},
{
"input": "10\n-10 -9 -8 -7 -6 6 7 8 9 10\n0000111110",
"output": "-5 5"
},
{
"input": "10\n-8 -9 -9 -7 -10 -10 -8 -8 -9 -10\n0000000011",
"output": "-7 1000000000"
},
{
"input": "11\n226 226 226 226 226 227 10000... | 61 | 6,041,600 | 0 | 1,102 | |
224 | Parallelepiped | [
"brute force",
"geometry",
"math"
] | null | null | You've got a rectangular parallelepiped with integer edge lengths. You know the areas of its three faces that have a common vertex. Your task is to find the sum of lengths of all 12 edges of this parallelepiped. | The first and the single line contains three space-separated integers β the areas of the parallelepiped's faces. The area's values are positive (<=><=0) and do not exceed 104. It is guaranteed that there exists at least one parallelepiped that satisfies the problem statement. | Print a single number β the sum of all edges of the parallelepiped. | [
"1 1 1\n",
"4 6 6\n"
] | [
"12\n",
"28\n"
] | In the first sample the parallelepiped has sizes 1βΓβ1βΓβ1, in the second oneΒ β 2βΓβ2βΓβ3. | [
{
"input": "1 1 1",
"output": "12"
},
{
"input": "4 6 6",
"output": "28"
},
{
"input": "20 10 50",
"output": "68"
},
{
"input": "9 4 36",
"output": "56"
},
{
"input": "324 9 36",
"output": "184"
},
{
"input": "1333 93 129",
"output": "308"
},
{... | 0 | 0 | -1 | 1,104 | |
817 | Imbalanced Array | [
"data structures",
"divide and conquer",
"dsu",
"sortings"
] | null | null | You are given an array *a* consisting of *n* elements. The imbalance value of some subsegment of this array is the difference between the maximum and minimum element from this segment. The imbalance value of the array is the sum of imbalance values of all subsegments of this array.
For example, the imbalance value of array [1,<=4,<=1] is 9, because there are 6 different subsegments of this array:
- [1] (from index 1 to index 1), imbalance value is 0; - [1,<=4] (from index 1 to index 2), imbalance value is 3; - [1,<=4,<=1] (from index 1 to index 3), imbalance value is 3; - [4] (from index 2 to index 2), imbalance value is 0; - [4,<=1] (from index 2 to index 3), imbalance value is 3; - [1] (from index 3 to index 3), imbalance value is 0;
You have to determine the imbalance value of the array *a*. | The first line contains one integer *n* (1<=β€<=*n*<=β€<=106) β size of the array *a*.
The second line contains *n* integers *a*1,<=*a*2... *a**n* (1<=β€<=*a**i*<=β€<=106) β elements of the array. | Print one integer β the imbalance value of *a*. | [
"3\n1 4 1\n"
] | [
"9\n"
] | none | [
{
"input": "3\n1 4 1",
"output": "9"
},
{
"input": "10\n1 1 1 1 1 1 1 1 1 1",
"output": "0"
},
{
"input": "10\n1 4 4 3 5 2 4 2 4 5",
"output": "123"
},
{
"input": "10\n9 6 8 5 5 2 8 9 2 2",
"output": "245"
},
{
"input": "30\n4 5 2 2 5 2 3 4 3 3 2 1 3 4 4 5 3 3 1 5... | 2,000 | 60,825,600 | 0 | 1,110 | |
988 | Diverse Team | [
"brute force",
"implementation"
] | null | null | There are $n$ students in a school class, the rating of the $i$-th student on Codehorses is $a_i$. You have to form a team consisting of $k$ students ($1 \le k \le n$) such that the ratings of all team members are distinct.
If it is impossible to form a suitable team, print "NO" (without quotes). Otherwise print "YES", and then print $k$ distinct numbers which should be the indices of students in the team you form. If there are multiple answers, print any of them. | The first line contains two integers $n$ and $k$ ($1 \le k \le n \le 100$) β the number of students and the size of the team you have to form.
The second line contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 100$), where $a_i$ is the rating of $i$-th student. | If it is impossible to form a suitable team, print "NO" (without quotes). Otherwise print "YES", and then print $k$ distinct integers from $1$ to $n$ which should be the indices of students in the team you form. All the ratings of the students in the team should be distinct. You may print the indices in any order. If there are multiple answers, print any of them.
Assume that the students are numbered from $1$ to $n$. | [
"5 3\n15 13 15 15 12\n",
"5 4\n15 13 15 15 12\n",
"4 4\n20 10 40 30\n"
] | [
"YES\n1 2 5 \n",
"NO\n",
"YES\n1 2 3 4 \n"
] | All possible answers for the first example:
- {1 2 5} - {2 3 5} - {2 4 5}
Note that the order does not matter. | [
{
"input": "5 3\n15 13 15 15 12",
"output": "YES\n1 2 5 "
},
{
"input": "5 4\n15 13 15 15 12",
"output": "NO"
},
{
"input": "4 4\n20 10 40 30",
"output": "YES\n1 2 3 4 "
},
{
"input": "1 1\n1",
"output": "YES\n1 "
},
{
"input": "100 53\n16 17 1 2 27 5 9 9 53 24 17... | 61 | 6,758,400 | 0 | 1,112 | |
131 | cAPS lOCK | [
"implementation",
"strings"
] | null | null | wHAT DO WE NEED cAPS LOCK FOR?
Caps lock is a computer keyboard key. Pressing it sets an input mode in which typed letters are capital by default. If it is pressed by accident, it leads to accidents like the one we had in the first passage.
Let's consider that a word has been typed with the Caps lock key accidentally switched on, if:
- either it only contains uppercase letters; - or all letters except for the first one are uppercase.
In this case we should automatically change the case of all letters. For example, the case of the letters that form words "hELLO", "HTTP", "z" should be changed.
Write a program that applies the rule mentioned above. If the rule cannot be applied, the program should leave the word unchanged. | The first line of the input data contains a word consisting of uppercase and lowercase Latin letters. The word's length is from 1 to 100 characters, inclusive. | Print the result of the given word's processing. | [
"cAPS\n",
"Lock\n"
] | [
"Caps",
"Lock\n"
] | none | [
{
"input": "cAPS",
"output": "Caps"
},
{
"input": "Lock",
"output": "Lock"
},
{
"input": "cAPSlOCK",
"output": "cAPSlOCK"
},
{
"input": "CAPs",
"output": "CAPs"
},
{
"input": "LoCK",
"output": "LoCK"
},
{
"input": "OOPS",
"output": "oops"
},
{
... | 31 | 0 | 0 | 1,113 | |
946 | String Transformation | [
"greedy",
"strings"
] | null | null | You are given a string *s* consisting of |*s*| small english letters.
In one move you can replace any character of this string to the next character in alphabetical order (a will be replaced with b, s will be replaced with t, etc.). You cannot replace letter z with any other letter.
Your target is to make some number of moves (not necessary minimal) to get string abcdefghijklmnopqrstuvwxyz (english alphabet) as a subsequence. Subsequence of the string is the string that is obtained by deleting characters at some positions. You need to print the string that will be obtained from the given string and will be contain english alphabet as a subsequence or say that it is impossible. | The only one line of the input consisting of the string *s* consisting of |*s*| (1<=β€<=|*s*|<=β€<=105) small english letters. | If you can get a string that can be obtained from the given string and will contain english alphabet as a subsequence, print it. Otherwise print Β«-1Β» (without quotes). | [
"aacceeggiikkmmooqqssuuwwyy\n",
"thereisnoanswer\n"
] | [
"abcdefghijklmnopqrstuvwxyz\n",
"-1\n"
] | none | [
{
"input": "aacceeggiikkmmooqqssuuwwyy",
"output": "abcdefghijklmnopqrstuvwxyz"
},
{
"input": "thereisnoanswer",
"output": "-1"
},
{
"input": "jqcfvsaveaixhioaaeephbmsmfcgdyawscpyioybkgxlcrhaxs",
"output": "-1"
},
{
"input": "rtdacjpsjjmjdhcoprjhaenlwuvpfqzurnrswngmpnkdnunaen... | 46 | 0 | 0 | 1,115 | |
985 | Sand Fortress | [
"binary search",
"constructive algorithms",
"math"
] | null | null | You are going to the beach with the idea to build the greatest sand castle ever in your head! The beach is not as three-dimensional as you could have imagined, it can be decribed as a line of spots to pile up sand pillars. Spots are numbered 1 through infinity from left to right.
Obviously, there is not enough sand on the beach, so you brought *n* packs of sand with you. Let height *h**i* of the sand pillar on some spot *i* be the number of sand packs you spent on it. You can't split a sand pack to multiple pillars, all the sand from it should go to a single one. There is a fence of height equal to the height of pillar with *H* sand packs to the left of the first spot and you should prevent sand from going over it.
Finally you ended up with the following conditions to building the castle:
- *h*1<=β€<=*H*: no sand from the leftmost spot should go over the fence; - For any |*h**i*<=-<=*h**i*<=+<=1|<=β€<=1: large difference in heights of two neighboring pillars can lead sand to fall down from the higher one to the lower, you really don't want this to happen; - : you want to spend all the sand you brought with you.
As you have infinite spots to build, it is always possible to come up with some valid castle structure. Though you want the castle to be as compact as possible.
Your task is to calculate the minimum number of spots you can occupy so that all the aforementioned conditions hold. | The only line contains two integer numbers *n* and *H* (1<=β€<=*n*,<=*H*<=β€<=1018) β the number of sand packs you have and the height of the fence, respectively. | Print the minimum number of spots you can occupy so the all the castle building conditions hold. | [
"5 2\n",
"6 8\n"
] | [
"3\n",
"3\n"
] | Here are the heights of some valid castles:
- *n*β=β5,β*H*β=β2,β[2,β2,β1,β0,β...],β[2,β1,β1,β1,β0,β...],β[1,β0,β1,β2,β1,β0,β...] - *n*β=β6,β*H*β=β8,β[3,β2,β1,β0,β...],β[2,β2,β1,β1,β0,β...],β[0,β1,β0,β1,β2,β1,β1,β0...] (this one has 5 spots occupied)
The first list for both cases is the optimal answer, 3 spots are occupied in them.
And here are some invalid ones:
- *n*β=β5,β*H*β=β2,β[3,β2,β0,β...],β[2,β3,β0,β...],β[1,β0,β2,β2,β...] - *n*β=β6,β*H*β=β8,β[2,β2,β2,β0,β...],β[6,β0,β...],β[1,β4,β1,β0...],β[2,β2,β1,β0,β...] | [
{
"input": "5 2",
"output": "3"
},
{
"input": "6 8",
"output": "3"
},
{
"input": "20 4",
"output": "7"
},
{
"input": "1000000000000000000 1000000000000000000",
"output": "1414213562"
},
{
"input": "1 1",
"output": "1"
},
{
"input": "1 10000000000000000... | 78 | 0 | 0 | 1,116 | |
735 | Taxes | [
"math",
"number theory"
] | null | null | Mr. Funt now lives in a country with a very specific tax laws. The total income of mr. Funt during this year is equal to *n* (*n*<=β₯<=2) burles and the amount of tax he has to pay is calculated as the maximum divisor of *n* (not equal to *n*, of course). For example, if *n*<==<=6 then Funt has to pay 3 burles, while for *n*<==<=25 he needs to pay 5 and if *n*<==<=2 he pays only 1 burle.
As mr. Funt is a very opportunistic person he wants to cheat a bit. In particular, he wants to split the initial *n* in several parts *n*1<=+<=*n*2<=+<=...<=+<=*n**k*<==<=*n* (here *k* is arbitrary, even *k*<==<=1 is allowed) and pay the taxes for each part separately. He can't make some part equal to 1 because it will reveal him. So, the condition *n**i*<=β₯<=2 should hold for all *i* from 1 to *k*.
Ostap Bender wonders, how many money Funt has to pay (i.e. minimal) if he chooses and optimal way to split *n* in parts. | The first line of the input contains a single integer *n* (2<=β€<=*n*<=β€<=2Β·109)Β β the total year income of mr. Funt. | Print one integerΒ β minimum possible number of burles that mr. Funt has to pay as a tax. | [
"4\n",
"27\n"
] | [
"2\n",
"3\n"
] | none | [
{
"input": "4",
"output": "2"
},
{
"input": "27",
"output": "3"
},
{
"input": "3",
"output": "1"
},
{
"input": "5",
"output": "1"
},
{
"input": "10",
"output": "2"
},
{
"input": "2000000000",
"output": "2"
},
{
"input": "26",
"output": ... | 1,949 | 268,390,400 | 0 | 1,118 | |
0 | none | [
"none"
] | null | null | It's Piegirl's birthday soon, and Pieguy has decided to buy her a bouquet of flowers and a basket of chocolates.
The flower shop has *F* different types of flowers available. The *i*-th type of flower always has exactly *p**i* petals. Pieguy has decided to buy a bouquet consisting of exactly *N* flowers. He may buy the same type of flower multiple times. The *N* flowers are then arranged into a bouquet. The position of the flowers within a bouquet matters. You can think of a bouquet as an ordered list of flower types.
The chocolate shop sells chocolates in boxes. There are *B* different types of boxes available. The *i*-th type of box contains *c**i* pieces of chocolate. Pieguy can buy any number of boxes, and can buy the same type of box multiple times. He will then place these boxes into a basket. The position of the boxes within the basket matters. You can think of the basket as an ordered list of box types.
Pieguy knows that Piegirl likes to pluck a petal from a flower before eating each piece of chocolate. He would like to ensure that she eats the last piece of chocolate from the last box just after plucking the last petal from the last flower. That is, the total number of petals on all the flowers in the bouquet should equal the total number of pieces of chocolate in all the boxes in the basket.
How many different bouquet+basket combinations can Pieguy buy? The answer may be very large, so compute it modulo 1000000007<==<=109<=+<=7. | The first line of input will contain integers *F*, *B*, and *N* (1<=β€<=*F*<=β€<=10,<=1<=β€<=*B*<=β€<=100,<=1<=β€<=*N*<=β€<=1018), the number of types of flowers, the number of types of boxes, and the number of flowers that must go into the bouquet, respectively.
The second line of input will contain *F* integers *p*1,<=*p*2,<=...,<=*p**F* (1<=β€<=*p**i*<=β€<=109), the numbers of petals on each of the flower types.
The third line of input will contain *B* integers *c*1,<=*c*2,<=...,<=*c**B* (1<=β€<=*c**i*<=β€<=250), the number of pieces of chocolate in each of the box types. | Print the number of bouquet+basket combinations Pieguy can buy, modulo 1000000007<==<=109<=+<=7. | [
"2 3 3\n3 5\n10 3 7\n",
"6 5 10\n9 3 3 4 9 9\n9 9 1 6 4\n"
] | [
"17\n",
"31415926\n"
] | In the first example, there is 1 way to make a bouquet with 9 petals (3β+β3β+β3), and 1 way to make a basket with 9 pieces of chocolate (3β+β3β+β3), for 1 possible combination. There are 3 ways to make a bouquet with 13 petals (3β+β5β+β5,β5β+β3β+β5,β5β+β5β+β3), and 5 ways to make a basket with 13 pieces of chocolate (3β+β10,β10β+β3,β3β+β3β+β7,β3β+β7β+β3,β7β+β3β+β3), for 15 more combinations. Finally there is 1 way to make a bouquet with 15 petals (5β+β5β+β5) and 1 way to make a basket with 15 pieces of chocolate (3β+β3β+β3β+β3β+β3), for 1 more combination.
Note that it is possible for multiple types of flowers to have the same number of petals. Such types are still considered different. Similarly different types of boxes may contain the same number of pieces of chocolate, but are still considered different. | [] | 46 | 0 | 0 | 1,119 | |
454 | Little Pony and Sort by Shift | [
"implementation"
] | null | null | One day, Twilight Sparkle is interested in how to sort a sequence of integers *a*1,<=*a*2,<=...,<=*a**n* in non-decreasing order. Being a young unicorn, the only operation she can perform is a unit shift. That is, she can move the last element of the sequence to its beginning:
Help Twilight Sparkle to calculate: what is the minimum number of operations that she needs to sort the sequence? | The first line contains an integer *n* (2<=β€<=*n*<=β€<=105). The second line contains *n* integer numbers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=105). | If it's impossible to sort the sequence output -1. Otherwise output the minimum number of operations Twilight Sparkle needs to sort it. | [
"2\n2 1\n",
"3\n1 3 2\n",
"2\n1 2\n"
] | [
"1\n",
"-1\n",
"0\n"
] | none | [
{
"input": "2\n2 1",
"output": "1"
},
{
"input": "3\n1 3 2",
"output": "-1"
},
{
"input": "2\n1 2",
"output": "0"
},
{
"input": "6\n3 4 5 6 3 2",
"output": "-1"
},
{
"input": "3\n1 2 1",
"output": "1"
},
{
"input": "5\n1 1 2 1 1",
"output": "2"
}... | 171 | 10,342,400 | 0 | 1,120 | |
350 | Bombs | [
"greedy",
"implementation",
"sortings"
] | null | null | You've got a robot, its task is destroying bombs on a square plane. Specifically, the square plane contains *n* bombs, the *i*-th bomb is at point with coordinates (*x**i*,<=*y**i*). We know that no two bombs are at the same point and that no bomb is at point with coordinates (0,<=0). Initially, the robot is at point with coordinates (0,<=0). Also, let's mark the robot's current position as (*x*,<=*y*). In order to destroy all the bombs, the robot can perform three types of operations:
1. Operation has format "1 k dir". To perform the operation robot have to move in direction *dir* *k* (*k*<=β₯<=1) times. There are only 4 directions the robot can move in: "R", "L", "U", "D". During one move the robot can move from the current point to one of following points: (*x*<=+<=1,<=*y*), (*x*<=-<=1,<=*y*), (*x*,<=*y*<=+<=1), (*x*,<=*y*<=-<=1) (corresponding to directions). It is forbidden to move from point (*x*,<=*y*), if at least one point on the path (besides the destination point) contains a bomb. 1. Operation has format "2". To perform the operation robot have to pick a bomb at point (*x*,<=*y*) and put it in a special container. Thus, the robot can carry the bomb from any point to any other point. The operation cannot be performed if point (*x*,<=*y*) has no bomb. It is forbidden to pick a bomb if the robot already has a bomb in its container. 1. Operation has format "3". To perform the operation robot have to take a bomb out of the container and destroy it. You are allowed to perform this operation only if the robot is at point (0,<=0). It is forbidden to perform the operation if the container has no bomb.
Help the robot and find the shortest possible sequence of operations he can perform to destroy all bombs on the coordinate plane. | The first line contains a single integer *n* (1<=β€<=*n*<=β€<=105) β the number of bombs on the coordinate plane. Next *n* lines contain two integers each. The *i*-th line contains numbers (*x**i*,<=*y**i*) (<=-<=109<=β€<=*x**i*,<=*y**i*<=β€<=109) β the coordinates of the *i*-th bomb. It is guaranteed that no two bombs are located at the same point and no bomb is at point (0,<=0). | In a single line print a single integer *k* β the minimum number of operations needed to destroy all bombs. On the next lines print the descriptions of these *k* operations. If there are multiple sequences, you can print any of them. It is guaranteed that there is the solution where *k*<=β€<=106. | [
"2\n1 1\n-1 -1\n",
"3\n5 0\n0 5\n1 0\n"
] | [
"12\n1 1 R\n1 1 U\n2\n1 1 L\n1 1 D\n3\n1 1 L\n1 1 D\n2\n1 1 R\n1 1 U\n3\n",
"12\n1 1 R\n2\n1 1 L\n3\n1 5 R\n2\n1 5 L\n3\n1 5 U\n2\n1 5 D\n3\n"
] | none | [
{
"input": "2\n1 1\n-1 -1",
"output": "12\n1 1 R\n1 1 U\n2\n1 1 L\n1 1 D\n3\n1 1 L\n1 1 D\n2\n1 1 R\n1 1 U\n3"
},
{
"input": "3\n5 0\n0 5\n1 0",
"output": "12\n1 1 R\n2\n1 1 L\n3\n1 5 R\n2\n1 5 L\n3\n1 5 U\n2\n1 5 D\n3"
},
{
"input": "1\n-277226476 314722425",
"output": "6\n1 2772264... | 1,902 | 55,808,000 | 3 | 1,121 | |
348 | Mafia | [
"binary search",
"math",
"sortings"
] | null | null | One day *n* friends gathered together to play "Mafia". During each round of the game some player must be the supervisor and other *n*<=-<=1 people take part in the game. For each person we know in how many rounds he wants to be a player, not the supervisor: the *i*-th person wants to play *a**i* rounds. What is the minimum number of rounds of the "Mafia" game they need to play to let each person play at least as many rounds as they want? | The first line contains integer *n* (3<=β€<=*n*<=β€<=105). The second line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=β€<=*a**i*<=β€<=109) β the *i*-th number in the list is the number of rounds the *i*-th person wants to play. | In a single line print a single integer β the minimum number of game rounds the friends need to let the *i*-th person play at least *a**i* rounds.
Please, do not use the %lld specifier to read or write 64-bit integers in Π‘++. It is preferred to use the cin, cout streams or the %I64d specifier. | [
"3\n3 2 2\n",
"4\n2 2 2 2\n"
] | [
"4\n",
"3\n"
] | You don't need to know the rules of "Mafia" to solve this problem. If you're curious, it's a game Russia got from the Soviet times: http://en.wikipedia.org/wiki/Mafia_(party_game). | [
{
"input": "3\n3 2 2",
"output": "4"
},
{
"input": "4\n2 2 2 2",
"output": "3"
},
{
"input": "7\n9 7 7 8 8 7 8",
"output": "9"
},
{
"input": "10\n13 12 10 13 13 14 10 10 12 12",
"output": "14"
},
{
"input": "10\n94 96 91 95 99 94 96 92 95 99",
"output": "106"
... | 0 | 0 | -1 | 1,124 | |
691 | s-palindrome | [
"implementation",
"strings"
] | null | null | Let's call a string "s-palindrome" if it is symmetric about the middle of the string. For example, the string "oHo" is "s-palindrome", but the string "aa" is not. The string "aa" is not "s-palindrome", because the second half of it is not a mirror reflection of the first half.
You are given a string *s*. Check if the string is "s-palindrome". | The only line contains the string *s* (1<=β€<=|*s*|<=β€<=1000) which consists of only English letters. | Print "TAK" if the string *s* is "s-palindrome" and "NIE" otherwise. | [
"oXoxoXo\n",
"bod\n",
"ER\n"
] | [
"TAK\n",
"TAK\n",
"NIE\n"
] | none | [
{
"input": "oXoxoXo",
"output": "TAK"
},
{
"input": "bod",
"output": "TAK"
},
{
"input": "ER",
"output": "NIE"
},
{
"input": "o",
"output": "TAK"
},
{
"input": "a",
"output": "NIE"
},
{
"input": "opo",
"output": "NIE"
},
{
"input": "HCMoxkg... | 62 | 307,200 | 0 | 1,125 | |
602 | Two Bases | [
"brute force",
"implementation"
] | null | null | After seeing the "ALL YOUR BASE ARE BELONG TO US" meme for the first time, numbers *X* and *Y* realised that they have different bases, which complicated their relations.
You're given a number *X* represented in base *b**x* and a number *Y* represented in base *b**y*. Compare those two numbers. | The first line of the input contains two space-separated integers *n* and *b**x* (1<=β€<=*n*<=β€<=10, 2<=β€<=*b**x*<=β€<=40), where *n* is the number of digits in the *b**x*-based representation of *X*.
The second line contains *n* space-separated integers *x*1,<=*x*2,<=...,<=*x**n* (0<=β€<=*x**i*<=<<=*b**x*) β the digits of *X*. They are given in the order from the most significant digit to the least significant one.
The following two lines describe *Y* in the same way: the third line contains two space-separated integers *m* and *b**y* (1<=β€<=*m*<=β€<=10, 2<=β€<=*b**y*<=β€<=40, *b**x*<=β <=*b**y*), where *m* is the number of digits in the *b**y*-based representation of *Y*, and the fourth line contains *m* space-separated integers *y*1,<=*y*2,<=...,<=*y**m* (0<=β€<=*y**i*<=<<=*b**y*) β the digits of *Y*.
There will be no leading zeroes. Both *X* and *Y* will be positive. All digits of both numbers are given in the standard decimal numeral system. | Output a single character (quotes for clarity):
- '<' if *X*<=<<=*Y* - '>' if *X*<=><=*Y* - '=' if *X*<==<=*Y* | [
"6 2\n1 0 1 1 1 1\n2 10\n4 7\n",
"3 3\n1 0 2\n2 5\n2 4\n",
"7 16\n15 15 4 0 0 7 10\n7 9\n4 8 0 3 1 5 0\n"
] | [
"=\n",
"<\n",
">\n"
] | In the first sample, *X*β=β101111<sub class="lower-index">2</sub>β=β47<sub class="lower-index">10</sub>β=β*Y*.
In the second sample, *X*β=β102<sub class="lower-index">3</sub>β=β21<sub class="lower-index">5</sub> and *Y*β=β24<sub class="lower-index">5</sub>β=β112<sub class="lower-index">3</sub>, thus *X*β<β*Y*.
In the third sample, <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/603a342b0ae3e56fed542d1c50c0a5ff6ce2cbaa.png" style="max-width: 100.0%;max-height: 100.0%;"/> and *Y*β=β4803150<sub class="lower-index">9</sub>. We may notice that *X* starts with much larger digits and *b*<sub class="lower-index">*x*</sub> is much larger than *b*<sub class="lower-index">*y*</sub>, so *X* is clearly larger than *Y*. | [
{
"input": "6 2\n1 0 1 1 1 1\n2 10\n4 7",
"output": "="
},
{
"input": "3 3\n1 0 2\n2 5\n2 4",
"output": "<"
},
{
"input": "7 16\n15 15 4 0 0 7 10\n7 9\n4 8 0 3 1 5 0",
"output": ">"
},
{
"input": "2 2\n1 0\n2 3\n1 0",
"output": "<"
},
{
"input": "2 2\n1 0\n1 3\n1"... | 77 | 0 | 3 | 1,127 | |
508 | Pasha and Pixels | [
"brute force"
] | null | null | Pasha loves his phone and also putting his hair up... But the hair is now irrelevant.
Pasha has installed a new game to his phone. The goal of the game is following. There is a rectangular field consisting of *n* row with *m* pixels in each row. Initially, all the pixels are colored white. In one move, Pasha can choose any pixel and color it black. In particular, he can choose the pixel that is already black, then after the boy's move the pixel does not change, that is, it remains black. Pasha loses the game when a 2<=Γ<=2 square consisting of black pixels is formed.
Pasha has made a plan of *k* moves, according to which he will paint pixels. Each turn in his plan is represented as a pair of numbers *i* and *j*, denoting respectively the row and the column of the pixel to be colored on the current move.
Determine whether Pasha loses if he acts in accordance with his plan, and if he does, on what move the 2<=Γ<=2 square consisting of black pixels is formed. | The first line of the input contains three integers *n*,<=*m*,<=*k* (1<=β€<=*n*,<=*m*<=β€<=1000, 1<=β€<=*k*<=β€<=105)Β β the number of rows, the number of columns and the number of moves that Pasha is going to perform.
The next *k* lines contain Pasha's moves in the order he makes them. Each line contains two integers *i* and *j* (1<=β€<=*i*<=β€<=*n*, 1<=β€<=*j*<=β€<=*m*), representing the row number and column number of the pixel that was painted during a move. | If Pasha loses, print the number of the move when the 2<=Γ<=2 square consisting of black pixels is formed.
If Pasha doesn't lose, that is, no 2<=Γ<=2 square consisting of black pixels is formed during the given *k* moves, print 0. | [
"2 2 4\n1 1\n1 2\n2 1\n2 2\n",
"2 3 6\n2 3\n2 2\n1 3\n2 2\n1 2\n1 1\n",
"5 3 7\n2 3\n1 2\n1 1\n4 1\n3 1\n5 3\n3 2\n"
] | [
"4\n",
"5\n",
"0\n"
] | none | [
{
"input": "2 2 4\n1 1\n1 2\n2 1\n2 2",
"output": "4"
},
{
"input": "2 3 6\n2 3\n2 2\n1 3\n2 2\n1 2\n1 1",
"output": "5"
},
{
"input": "5 3 7\n2 3\n1 2\n1 1\n4 1\n3 1\n5 3\n3 2",
"output": "0"
},
{
"input": "3 3 11\n2 1\n3 1\n1 1\n1 3\n1 2\n2 3\n3 3\n3 2\n2 2\n1 3\n3 3",
... | 592 | 13,516,800 | 3 | 1,132 | |
918 | Eleven | [
"brute force",
"implementation"
] | null | null | Eleven wants to choose a new name for herself. As a bunch of geeks, her friends suggested an algorithm to choose a name for her. Eleven wants her name to have exactly *n* characters.
Her friend suggested that her name should only consist of uppercase and lowercase letters 'O'. More precisely, they suggested that the *i*-th letter of her name should be 'O' (uppercase) if *i* is a member of Fibonacci sequence, and 'o' (lowercase) otherwise. The letters in the name are numbered from 1 to *n*. Fibonacci sequence is the sequence *f* where
- *f*1<==<=1, - *f*2<==<=1, - *f**n*<==<=*f**n*<=-<=2<=+<=*f**n*<=-<=1 (*n*<=><=2).
As her friends are too young to know what Fibonacci sequence is, they asked you to help Eleven determine her new name. | The first and only line of input contains an integer *n* (1<=β€<=*n*<=β€<=1000). | Print Eleven's new name on the first and only line of output. | [
"8\n",
"15\n"
] | [
"OOOoOooO\n",
"OOOoOooOooooOoo\n"
] | none | [
{
"input": "8",
"output": "OOOoOooO"
},
{
"input": "15",
"output": "OOOoOooOooooOoo"
},
{
"input": "85",
"output": "OOOoOooOooooOoooooooOooooooooooooOooooooooooooooooooooOoooooooooooooooooooooooooooooo"
},
{
"input": "381",
"output": "OOOoOooOooooOoooooooOooooooooooooOooo... | 61 | 0 | 3 | 1,134 |
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