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Insomnia cure
[ "constructive algorithms", "implementation", "math" ]
null
null
«One dragon. Two dragon. Three dragon», — the princess was counting. She had trouble falling asleep, and she got bored of counting lambs when she was nine. However, just counting dragons was boring as well, so she entertained herself at best she could. Tonight she imagined that all dragons were here to steal her, and she was fighting them off. Every *k*-th dragon got punched in the face with a frying pan. Every *l*-th dragon got his tail shut into the balcony door. Every *m*-th dragon got his paws trampled with sharp heels. Finally, she threatened every *n*-th dragon to call her mom, and he withdrew in panic. How many imaginary dragons suffered moral or physical damage tonight, if the princess counted a total of *d* dragons?
Input data contains integer numbers *k*,<=*l*,<=*m*,<=*n* and *d*, each number in a separate line (1<=≤<=*k*,<=*l*,<=*m*,<=*n*<=≤<=10, 1<=≤<=*d*<=≤<=105).
Output the number of damaged dragons.
[ "1\n2\n3\n4\n12\n", "2\n3\n4\n5\n24\n" ]
[ "12\n", "17\n" ]
In the first case every first dragon got punched with a frying pan. Some of the dragons suffered from other reasons as well, but the pan alone would be enough. In the second case dragons 1, 7, 11, 13, 17, 19 and 23 escaped unharmed.
[ { "input": "1\n2\n3\n4\n12", "output": "12" }, { "input": "2\n3\n4\n5\n24", "output": "17" }, { "input": "1\n1\n1\n1\n100000", "output": "100000" }, { "input": "10\n9\n8\n7\n6", "output": "0" }, { "input": "8\n4\n4\n3\n65437", "output": "32718" }, { "i...
92
0
-1
711
552
Vanya and Books
[ "implementation", "math" ]
null
null
Vanya got an important task — he should enumerate books in the library and label each book with its number. Each of the *n* books should be assigned with a number from 1 to *n*. Naturally, distinct books should be assigned distinct numbers. Vanya wants to know how many digits he will have to write down as he labels the books.
The first line contains integer *n* (1<=≤<=*n*<=≤<=109) — the number of books in the library.
Print the number of digits needed to number all the books.
[ "13\n", "4\n" ]
[ "17\n", "4\n" ]
Note to the first test. The books get numbers 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, which totals to 17 digits. Note to the second sample. The books get numbers 1, 2, 3, 4, which totals to 4 digits.
[ { "input": "13", "output": "17" }, { "input": "4", "output": "4" }, { "input": "100", "output": "192" }, { "input": "99", "output": "189" }, { "input": "1000000000", "output": "8888888899" }, { "input": "1000000", "output": "5888896" }, { "...
1,000
1,536,000
0
714
421
Pasha and Hamsters
[ "constructive algorithms", "implementation" ]
null
null
Pasha has two hamsters: Arthur and Alexander. Pasha put *n* apples in front of them. Pasha knows which apples Arthur likes. Similarly, Pasha knows which apples Alexander likes. Pasha doesn't want any conflict between the hamsters (as they may like the same apple), so he decided to distribute the apples between the hamsters on his own. He is going to give some apples to Arthur and some apples to Alexander. It doesn't matter how many apples each hamster gets but it is important that each hamster gets only the apples he likes. It is possible that somebody doesn't get any apples. Help Pasha distribute all the apples between the hamsters. Note that Pasha wants to distribute all the apples, not just some of them.
The first line contains integers *n*, *a*, *b* (1<=≤<=*n*<=≤<=100; 1<=≤<=*a*,<=*b*<=≤<=*n*) — the number of apples Pasha has, the number of apples Arthur likes and the number of apples Alexander likes, correspondingly. The next line contains *a* distinct integers — the numbers of the apples Arthur likes. The next line contains *b* distinct integers — the numbers of the apples Alexander likes. Assume that the apples are numbered from 1 to *n*. The input is such that the answer exists.
Print *n* characters, each of them equals either 1 or 2. If the *i*-h character equals 1, then the *i*-th apple should be given to Arthur, otherwise it should be given to Alexander. If there are multiple correct answers, you are allowed to print any of them.
[ "4 2 3\n1 2\n2 3 4\n", "5 5 2\n3 4 1 2 5\n2 3\n" ]
[ "1 1 2 2\n", "1 1 1 1 1\n" ]
none
[ { "input": "4 2 3\n1 2\n2 3 4", "output": "1 1 2 2" }, { "input": "5 5 2\n3 4 1 2 5\n2 3", "output": "1 1 1 1 1" }, { "input": "100 69 31\n1 3 4 5 6 7 8 9 10 11 12 14 15 16 17 18 19 20 21 24 26 27 29 31 37 38 39 40 44 46 48 49 50 51 53 55 56 57 58 59 60 61 63 64 65 66 67 68 69 70 71 72 7...
62
0
3
716
205
Little Elephant and Rozdil
[ "brute force", "implementation" ]
null
null
The Little Elephant loves Ukraine very much. Most of all he loves town Rozdol (ukr. "Rozdil"). However, Rozdil is dangerous to settle, so the Little Elephant wants to go to some other town. The Little Elephant doesn't like to spend much time on travelling, so for his journey he will choose a town that needs minimum time to travel to. If there are multiple such cities, then the Little Elephant won't go anywhere. For each town except for Rozdil you know the time needed to travel to this town. Find the town the Little Elephant will go to or print "Still Rozdil", if he stays in Rozdil.
The first line contains a single integer *n* (1<=≤<=*n*<=≤<=105) — the number of cities. The next line contains *n* integers, separated by single spaces: the *i*-th integer represents the time needed to go from town Rozdil to the *i*-th town. The time values are positive integers, not exceeding 109. You can consider the cities numbered from 1 to *n*, inclusive. Rozdil is not among the numbered cities.
Print the answer on a single line — the number of the town the Little Elephant will go to. If there are multiple cities with minimum travel time, print "Still Rozdil" (without the quotes).
[ "2\n7 4\n", "7\n7 4 47 100 4 9 12\n" ]
[ "2\n", "Still Rozdil\n" ]
In the first sample there are only two cities where the Little Elephant can go. The travel time for the first town equals 7, to the second one — 4. The town which is closest to Rodzil (the only one) is the second one, so the answer is 2. In the second sample the closest cities are cities two and five, the travelling time to both of them equals 4, so the answer is "Still Rozdil".
[ { "input": "2\n7 4", "output": "2" }, { "input": "7\n7 4 47 100 4 9 12", "output": "Still Rozdil" }, { "input": "1\n47", "output": "1" }, { "input": "2\n1000000000 1000000000", "output": "Still Rozdil" }, { "input": "7\n7 6 5 4 3 2 1", "output": "7" }, { ...
154
13,516,800
3
718
526
King of Thieves
[ "brute force", "implementation" ]
null
null
In this problem you will meet the simplified model of game King of Thieves. In a new ZeptoLab game called "King of Thieves" your aim is to reach a chest with gold by controlling your character, avoiding traps and obstacles on your way. An interesting feature of the game is that you can design your own levels that will be available to other players. Let's consider the following simple design of a level. A dungeon consists of *n* segments located at a same vertical level, each segment is either a platform that character can stand on, or a pit with a trap that makes player lose if he falls into it. All segments have the same length, platforms on the scheme of the level are represented as '*' and pits are represented as '.'. One of things that affects speedrun characteristics of the level is a possibility to perform a series of consecutive jumps of the same length. More formally, when the character is on the platform number *i*1, he can make a sequence of jumps through the platforms *i*1<=&lt;<=*i*2<=&lt;<=...<=&lt;<=*i**k*, if *i*2<=-<=*i*1<==<=*i*3<=-<=*i*2<==<=...<==<=*i**k*<=-<=*i**k*<=-<=1. Of course, all segments *i*1,<=*i*2,<=... *i**k* should be exactly the platforms, not pits. Let's call a level to be good if you can perform a sequence of four jumps of the same length or in the other words there must be a sequence *i*1,<=*i*2,<=...,<=*i*5, consisting of five platforms so that the intervals between consecutive platforms are of the same length. Given the scheme of the level, check if it is good.
The first line contains integer *n* (1<=≤<=*n*<=≤<=100) — the number of segments on the level. Next line contains the scheme of the level represented as a string of *n* characters '*' and '.'.
If the level is good, print the word "yes" (without the quotes), otherwise print the word "no" (without the quotes).
[ "16\n.**.*..*.***.**.\n", "11\n.*.*...*.*.\n" ]
[ "yes", "no" ]
In the first sample test you may perform a sequence of jumps through platforms 2, 5, 8, 11, 14.
[ { "input": "16\n.**.*..*.***.**.", "output": "yes" }, { "input": "11\n.*.*...*.*.", "output": "no" }, { "input": "53\n*.*.****.*.*......**....**.***.*.*.**.*.*.***...*..*.", "output": "yes" }, { "input": "71\n**.**..*****.*.*.*.********.....*****.****.*..***...*.*.*.**.****.*...
62
0
3
720
0
none
[ "none" ]
null
null
Santa Claus decided to disassemble his keyboard to clean it. After he returned all the keys back, he suddenly realized that some pairs of keys took each other's place! That is, Santa suspects that each key is either on its place, or on the place of another key, which is located exactly where the first key should be. In order to make sure that he's right and restore the correct order of keys, Santa typed his favorite patter looking only to his keyboard. You are given the Santa's favorite patter and the string he actually typed. Determine which pairs of keys could be mixed. Each key must occur in pairs at most once.
The input consists of only two strings *s* and *t* denoting the favorite Santa's patter and the resulting string. *s* and *t* are not empty and have the same length, which is at most 1000. Both strings consist only of lowercase English letters.
If Santa is wrong, and there is no way to divide some of keys into pairs and swap keys in each pair so that the keyboard will be fixed, print «-1» (without quotes). Otherwise, the first line of output should contain the only integer *k* (*k*<=≥<=0) — the number of pairs of keys that should be swapped. The following *k* lines should contain two space-separated letters each, denoting the keys which should be swapped. All printed letters must be distinct. If there are several possible answers, print any of them. You are free to choose the order of the pairs and the order of keys in a pair. Each letter must occur at most once. Santa considers the keyboard to be fixed if he can print his favorite patter without mistakes.
[ "helloworld\nehoolwlroz\n", "hastalavistababy\nhastalavistababy\n", "merrychristmas\nchristmasmerry\n" ]
[ "3\nh e\nl o\nd z\n", "0\n", "-1\n" ]
none
[ { "input": "helloworld\nehoolwlroz", "output": "3\nh e\nl o\nd z" }, { "input": "hastalavistababy\nhastalavistababy", "output": "0" }, { "input": "merrychristmas\nchristmasmerry", "output": "-1" }, { "input": "kusyvdgccw\nkusyvdgccw", "output": "0" }, { "input": "...
61
4,608,000
0
721
558
Amr and The Large Array
[ "implementation" ]
null
null
Amr has got a large array of size *n*. Amr doesn't like large arrays so he intends to make it smaller. Amr doesn't care about anything in the array except the beauty of it. The beauty of the array is defined to be the maximum number of times that some number occurs in this array. He wants to choose the smallest subsegment of this array such that the beauty of it will be the same as the original array. Help Amr by choosing the smallest subsegment possible.
The first line contains one number *n* (1<=≤<=*n*<=≤<=105), the size of the array. The second line contains *n* integers *a**i* (1<=≤<=*a**i*<=≤<=106), representing elements of the array.
Output two integers *l*,<=*r* (1<=≤<=*l*<=≤<=*r*<=≤<=*n*), the beginning and the end of the subsegment chosen respectively. If there are several possible answers you may output any of them.
[ "5\n1 1 2 2 1\n", "5\n1 2 2 3 1\n", "6\n1 2 2 1 1 2\n" ]
[ "1 5", "2 3", "1 5" ]
A subsegment *B* of an array *A* from *l* to *r* is an array of size *r* - *l* + 1 where *B*<sub class="lower-index">*i*</sub> = *A*<sub class="lower-index">*l* + *i* - 1</sub> for all 1 ≤ *i* ≤ *r* - *l* + 1
[ { "input": "5\n1 1 2 2 1", "output": "1 5" }, { "input": "5\n1 2 2 3 1", "output": "2 3" }, { "input": "6\n1 2 2 1 1 2", "output": "1 5" }, { "input": "10\n1 1000000 2 1000000 3 2 1000000 1 2 1", "output": "2 7" }, { "input": "10\n1 2 3 4 5 5 1 2 3 4", "output...
46
1,433,600
0
723
180
Mathematical Analysis Rocks!
[ "constructive algorithms", "implementation", "math" ]
null
null
Students of group 199 have written their lectures dismally. Now an exam on Mathematical Analysis is approaching and something has to be done asap (that is, quickly). Let's number the students of the group from 1 to *n*. Each student *i* (1<=≤<=*i*<=≤<=*n*) has a best friend *p*[*i*] (1<=≤<=*p*[*i*]<=≤<=*n*). In fact, each student is a best friend of exactly one student. In other words, all *p*[*i*] are different. It is possible that the group also has some really "special individuals" for who *i*<==<=*p*[*i*]. Each student wrote exactly one notebook of lecture notes. We know that the students agreed to act by the following algorithm: - on the first day of revising each student studies his own Mathematical Analysis notes, - in the morning of each following day each student gives the notebook to his best friend and takes a notebook from the student who calls him the best friend. Thus, on the second day the student *p*[*i*] (1<=≤<=*i*<=≤<=*n*) studies the *i*-th student's notes, on the third day the notes go to student *p*[*p*[*i*]] and so on. Due to some characteristics of the boys' friendship (see paragraph 1), each day each student has exactly one notebook to study. You are given two sequences that describe the situation on the third and fourth days of revising: - *a*1,<=*a*2,<=...,<=*a**n*, where *a**i* means the student who gets the *i*-th student's notebook on the third day of revising; - *b*1,<=*b*2,<=...,<=*b**n*, where *b**i* means the student who gets the *i*-th student's notebook on the fourth day of revising. You do not know array *p*, that is you do not know who is the best friend to who. Write a program that finds *p* by the given sequences *a* and *b*.
The first line contains integer *n* (1<=≤<=*n*<=≤<=105) — the number of students in the group. The second line contains sequence of different integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=*n*). The third line contains the sequence of different integers *b*1,<=*b*2,<=...,<=*b**n* (1<=≤<=*b**i*<=≤<=*n*).
Print sequence *n* of different integers *p*[1],<=*p*[2],<=...,<=*p*[*n*] (1<=≤<=*p*[*i*]<=≤<=*n*). It is guaranteed that the solution exists and that it is unique.
[ "4\n2 1 4 3\n3 4 2 1\n", "5\n5 2 3 1 4\n1 3 2 4 5\n", "2\n1 2\n2 1\n" ]
[ "4 3 1 2 ", "4 3 2 5 1 ", "2 1 " ]
none
[ { "input": "4\n2 1 4 3\n3 4 2 1", "output": "4 3 1 2 " }, { "input": "5\n5 2 3 1 4\n1 3 2 4 5", "output": "4 3 2 5 1 " }, { "input": "2\n1 2\n2 1", "output": "2 1 " }, { "input": "1\n1\n1", "output": "1 " }, { "input": "2\n1 2\n1 2", "output": "1 2 " }, { ...
248
19,763,200
3
724
960
Check the string
[ "implementation" ]
null
null
A has a string consisting of some number of lowercase English letters 'a'. He gives it to his friend B who appends some number of letters 'b' to the end of this string. Since both A and B like the characters 'a' and 'b', they have made sure that at this point, at least one 'a' and one 'b' exist in the string. B now gives this string to C and he appends some number of letters 'c' to the end of the string. However, since C is a good friend of A and B, the number of letters 'c' he appends is equal to the number of 'a' or to the number of 'b' in the string. It is also possible that the number of letters 'c' equals both to the number of letters 'a' and to the number of letters 'b' at the same time. You have a string in your hands, and you want to check if it is possible to obtain the string in this way or not. If it is possible to obtain the string, print "YES", otherwise print "NO" (without the quotes).
The first and only line consists of a string $S$ ($ 1 \le |S| \le 5\,000 $). It is guaranteed that the string will only consist of the lowercase English letters 'a', 'b', 'c'.
Print "YES" or "NO", according to the condition.
[ "aaabccc\n", "bbacc\n", "aabc\n" ]
[ "YES\n", "NO\n", "YES\n" ]
Consider first example: the number of 'c' is equal to the number of 'a'. Consider second example: although the number of 'c' is equal to the number of the 'b', the order is not correct. Consider third example: the number of 'c' is equal to the number of 'b'.
[ { "input": "aaabccc", "output": "YES" }, { "input": "bbacc", "output": "NO" }, { "input": "aabc", "output": "YES" }, { "input": "aabbcc", "output": "YES" }, { "input": "aaacccbb", "output": "NO" }, { "input": "abc", "output": "YES" }, { "in...
31
0
-1
725
628
New Skateboard
[ "dp" ]
null
null
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4. You are given a string *s* consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero. A substring of a string is a nonempty sequence of consecutive characters. For example if string *s* is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04. As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
The only line contains string *s* (1<=≤<=|*s*|<=≤<=3·105). The string *s* contains only digits from 0 to 9.
Print integer *a* — the number of substrings of the string *s* that are divisible by 4. Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
[ "124\n", "04\n", "5810438174\n" ]
[ "4\n", "3\n", "9\n" ]
none
[ { "input": "124", "output": "4" }, { "input": "04", "output": "3" }, { "input": "5810438174", "output": "9" }, { "input": "1", "output": "0" }, { "input": "039", "output": "1" }, { "input": "97247", "output": "6" }, { "input": "5810438174",...
327
1,024,000
3
727
813
Army Creation
[ "binary search", "data structures" ]
null
null
As you might remember from our previous rounds, Vova really likes computer games. Now he is playing a strategy game known as Rage of Empires. In the game Vova can hire *n* different warriors; *i*th warrior has the type *a**i*. Vova wants to create a balanced army hiring some subset of warriors. An army is called balanced if for each type of warrior present in the game there are not more than *k* warriors of this type in the army. Of course, Vova wants his army to be as large as possible. To make things more complicated, Vova has to consider *q* different plans of creating his army. *i*th plan allows him to hire only warriors whose numbers are not less than *l**i* and not greater than *r**i*. Help Vova to determine the largest size of a balanced army for each plan. Be aware that the plans are given in a modified way. See input section for details.
The first line contains two integers *n* and *k* (1<=≤<=*n*,<=*k*<=≤<=100000). The second line contains *n* integers *a*1, *a*2, ... *a**n* (1<=≤<=*a**i*<=≤<=100000). The third line contains one integer *q* (1<=≤<=*q*<=≤<=100000). Then *q* lines follow. *i*th line contains two numbers *x**i* and *y**i* which represent *i*th plan (1<=≤<=*x**i*,<=*y**i*<=≤<=*n*). You have to keep track of the answer to the last plan (let's call it *last*). In the beginning *last*<==<=0. Then to restore values of *l**i* and *r**i* for the *i*th plan, you have to do the following: 1. *l**i*<==<=((*x**i*<=+<=*last*) *mod* *n*)<=+<=1; 1. *r**i*<==<=((*y**i*<=+<=*last*) *mod* *n*)<=+<=1; 1. If *l**i*<=&gt;<=*r**i*, swap *l**i* and *r**i*.
Print *q* numbers. *i*th number must be equal to the maximum size of a balanced army when considering *i*th plan.
[ "6 2\n1 1 1 2 2 2\n5\n1 6\n4 3\n1 1\n2 6\n2 6\n" ]
[ "2\n4\n1\n3\n2\n" ]
In the first example the real plans are: 1. 1 2 1. 1 6 1. 6 6 1. 2 4 1. 4 6
[ { "input": "6 2\n1 1 1 2 2 2\n5\n1 6\n4 3\n1 1\n2 6\n2 6", "output": "2\n4\n1\n3\n2" }, { "input": "5 5\n3 4 4 2 1\n5\n5 5\n5 4\n5 4\n3 4\n5 5", "output": "1\n2\n2\n2\n1" }, { "input": "5 5\n2 1 2 4 1\n5\n5 3\n1 1\n5 1\n2 1\n2 3", "output": "4\n1\n2\n2\n5" }, { "input": "10 5...
2,000
6,144,000
0
728
776
Sherlock and his girlfriend
[ "constructive algorithms", "number theory" ]
null
null
Sherlock has a new girlfriend (so unlike him!). Valentine's day is coming and he wants to gift her some jewelry. He bought *n* pieces of jewelry. The *i*-th piece has price equal to *i*<=+<=1, that is, the prices of the jewelry are 2,<=3,<=4,<=... *n*<=+<=1. Watson gave Sherlock a challenge to color these jewelry pieces such that two pieces don't have the same color if the price of one piece is a prime divisor of the price of the other piece. Also, Watson asked him to minimize the number of different colors used. Help Sherlock complete this trivial task.
The only line contains single integer *n* (1<=≤<=*n*<=≤<=100000) — the number of jewelry pieces.
The first line of output should contain a single integer *k*, the minimum number of colors that can be used to color the pieces of jewelry with the given constraints. The next line should consist of *n* space-separated integers (between 1 and *k*) that specify the color of each piece in the order of increasing price. If there are multiple ways to color the pieces using *k* colors, you can output any of them.
[ "3\n", "4\n" ]
[ "2\n1 1 2 ", "2\n2 1 1 2\n" ]
In the first input, the colors for first, second and third pieces of jewelry having respective prices 2, 3 and 4 are 1, 1 and 2 respectively. In this case, as 2 is a prime divisor of 4, colors of jewelry having prices 2 and 4 must be distinct.
[ { "input": "3", "output": "2\n1 1 2 " }, { "input": "4", "output": "2\n1 1 2 1 " }, { "input": "17", "output": "2\n1 1 2 1 2 1 2 2 2 1 2 1 2 2 2 1 2 " }, { "input": "25", "output": "2\n1 1 2 1 2 1 2 2 2 1 2 1 2 2 2 1 2 1 2 2 2 1 2 2 2 " }, { "input": "85", "ou...
46
7,065,600
0
730
77
Heroes
[ "brute force", "implementation" ]
A. Heroes
2
256
The year of 2012 is coming... According to an ancient choradrican legend in this very year, in 2012, Diablo and his brothers Mephisto and Baal will escape from hell, and innumerable hordes of demons will enslave the human world. But seven brave heroes have already gathered on the top of a mountain Arreat to protect us mere mortals from the effect of this terrible evil. The seven great heroes are: amazon Anka, barbarian Chapay, sorceress Cleo, druid Troll, necromancer Dracul, paladin Snowy and a professional hit girl Hexadecimal. Heroes already know how much experience will be given for each of the three megabosses: *a* for Mephisto, *b* for Diablo and *c* for Baal. Here's the problem: heroes are as much as seven and megabosses are only three! Then our heroes decided to split into three teams, where each team will go to destroy their own megaboss. Each team member will receive a of experience, rounded down, where *x* will be the amount of experience for the killed megaboss and *y* — the number of people in the team. Heroes do not want to hurt each other's feelings, so they want to split into teams so that the difference between the hero who received the maximum number of experience and the hero who received the minimum number of experience were minimal. Since there can be several divisions into teams, then you need to find the one in which the total amount of liking in teams were maximum. It is known that some heroes like others. But if hero *p* likes hero *q*, this does not mean that the hero *q* likes hero *p*. No hero likes himself. The total amount of liking in teams is the amount of ordered pairs (*p*,<=*q*), such that heroes *p* and *q* are in the same group, and hero *p* likes hero *q* (but it is not important if hero *q* likes hero *p*). In case of heroes *p* and *q* likes each other and they are in the same group, this pair should be counted twice, as (*p*,<=*q*) and (*q*,<=*p*). A team can consist even of a single hero, but it is important that every megaboss was destroyed. All heroes must be involved in the campaign against evil. None of the heroes can be in more than one team. It is guaranteed that every hero is able to destroy any megaboss alone.
The first line contains a single non-negative integer *n* (0<=≤<=*n*<=≤<=42) — amount of liking between the heroes. Next *n* lines describe liking in the form "p likes q", meaning that the hero p likes the hero q (p <=≠<= q). Every liking is described in the input exactly once, no hero likes himself. In the last line are given three integers *a*, *b* and *c* (1<=≤<=*a*,<=*b*,<=*c*<=≤<=2·109), separated by spaces: the experience for Mephisto, the experience for Diablo and experience for Baal. In all the pretests, except for examples from the statement, the following condition is satisfied: *a*<==<=*b*<==<=*c*.
Print two integers — the minimal difference in the experience between two heroes who will receive the maximum and minimum number of experience points, and the maximal total amount of liking in teams (the number of friendships between heroes that end up in one team). When calculating the second answer, the team division should satisfy the difference-minimizing contraint. I.e. primary you should minimize the difference in the experience and secondary you should maximize the total amount of liking.
[ "3\nTroll likes Dracul\nDracul likes Anka\nSnowy likes Hexadecimal\n210 200 180\n", "2\nAnka likes Chapay\nChapay likes Anka\n10000 50 50\n" ]
[ "30 3\n", "1950 2\n" ]
A note to first example: it the first team should be Dracul, Troll and Anka, in the second one Hexadecimal and Snowy, and in the third Cleo и Chapay.
[ { "input": "3\nTroll likes Dracul\nDracul likes Anka\nSnowy likes Hexadecimal\n210 200 180", "output": "30 3" }, { "input": "2\nAnka likes Chapay\nChapay likes Anka\n10000 50 50", "output": "1950 2" }, { "input": "11\nSnowy likes Dracul\nAnka likes Dracul\nChapay likes Snowy\nHexadecimal...
218
307,200
0
731
5
Longest Regular Bracket Sequence
[ "constructive algorithms", "data structures", "dp", "greedy", "sortings", "strings" ]
C. Longest Regular Bracket Sequence
2
256
This is yet another problem dealing with regular bracket sequences. We should remind you that a bracket sequence is called regular, if by inserting «+» and «1» into it we can get a correct mathematical expression. For example, sequences «(())()», «()» and «(()(()))» are regular, while «)(», «(()» and «(()))(» are not. You are given a string of «(» and «)» characters. You are to find its longest substring that is a regular bracket sequence. You are to find the number of such substrings as well.
The first line of the input file contains a non-empty string, consisting of «(» and «)» characters. Its length does not exceed 106.
Print the length of the longest substring that is a regular bracket sequence, and the number of such substrings. If there are no such substrings, write the only line containing "0 1".
[ ")((())))(()())\n", "))(\n" ]
[ "6 2\n", "0 1\n" ]
none
[ { "input": ")((())))(()())", "output": "6 2" }, { "input": "))(", "output": "0 1" }, { "input": "()(())()", "output": "8 1" }, { "input": "((((()(((", "output": "2 1" }, { "input": "))))()())))", "output": "4 1" }, { "input": "(()())()(())()()())())()(...
1,652
38,092,800
3.516047
733
834
The Festive Evening
[ "data structures", "implementation" ]
null
null
It's the end of July – the time when a festive evening is held at Jelly Castle! Guests from all over the kingdom gather here to discuss new trends in the world of confectionery. Yet some of the things discussed here are not supposed to be disclosed to the general public: the information can cause discord in the kingdom of Sweetland in case it turns out to reach the wrong hands. So it's a necessity to not let any uninvited guests in. There are 26 entrances in Jelly Castle, enumerated with uppercase English letters from A to Z. Because of security measures, each guest is known to be assigned an entrance he should enter the castle through. The door of each entrance is opened right before the first guest's arrival and closed right after the arrival of the last guest that should enter the castle through this entrance. No two guests can enter the castle simultaneously. For an entrance to be protected from possible intrusion, a candy guard should be assigned to it. There are *k* such guards in the castle, so if there are more than *k* opened doors, one of them is going to be left unguarded! Notice that a guard can't leave his post until the door he is assigned to is closed. Slastyona had a suspicion that there could be uninvited guests at the evening. She knows the order in which the invited guests entered the castle, and wants you to help her check whether there was a moment when more than *k* doors were opened.
Two integers are given in the first string: the number of guests *n* and the number of guards *k* (1<=≤<=*n*<=≤<=106, 1<=≤<=*k*<=≤<=26). In the second string, *n* uppercase English letters *s*1*s*2... *s**n* are given, where *s**i* is the entrance used by the *i*-th guest.
Output «YES» if at least one door was unguarded during some time, and «NO» otherwise. You can output each letter in arbitrary case (upper or lower).
[ "5 1\nAABBB\n", "5 1\nABABB\n" ]
[ "NO\n", "YES\n" ]
In the first sample case, the door A is opened right before the first guest's arrival and closed when the second guest enters the castle. The door B is opened right before the arrival of the third guest, and closed after the fifth one arrives. One guard can handle both doors, as the first one is closed before the second one is opened. In the second sample case, the door B is opened before the second guest's arrival, but the only guard can't leave the door A unattended, as there is still one more guest that should enter the castle through this door.
[ { "input": "5 1\nAABBB", "output": "NO" }, { "input": "5 1\nABABB", "output": "YES" }, { "input": "26 1\nABCDEFGHIJKLMNOPQRSTUVWXYZ", "output": "NO" }, { "input": "27 1\nABCDEFGHIJKLMNOPQRSTUVWXYZA", "output": "YES" }, { "input": "5 2\nABACA", "output": "NO" ...
327
7,065,600
3
734
591
Wizards' Duel
[ "implementation", "math" ]
null
null
Harry Potter and He-Who-Must-Not-Be-Named engaged in a fight to the death once again. This time they are located at opposite ends of the corridor of length *l*. Two opponents simultaneously charge a deadly spell in the enemy. We know that the impulse of Harry's magic spell flies at a speed of *p* meters per second, and the impulse of You-Know-Who's magic spell flies at a speed of *q* meters per second. The impulses are moving through the corridor toward each other, and at the time of the collision they turn round and fly back to those who cast them without changing their original speeds. Then, as soon as the impulse gets back to it's caster, the wizard reflects it and sends again towards the enemy, without changing the original speed of the impulse. Since Harry has perfectly mastered the basics of magic, he knows that after the second collision both impulses will disappear, and a powerful explosion will occur exactly in the place of their collision. However, the young wizard isn't good at math, so he asks you to calculate the distance from his position to the place of the second meeting of the spell impulses, provided that the opponents do not change positions during the whole fight.
The first line of the input contains a single integer *l* (1<=≤<=*l*<=≤<=1<=000) — the length of the corridor where the fight takes place. The second line contains integer *p*, the third line contains integer *q* (1<=≤<=*p*,<=*q*<=≤<=500) — the speeds of magical impulses for Harry Potter and He-Who-Must-Not-Be-Named, respectively.
Print a single real number — the distance from the end of the corridor, where Harry is located, to the place of the second meeting of the spell impulses. Your answer will be considered correct if its absolute or relative error will not exceed 10<=-<=4. Namely: let's assume that your answer equals *a*, and the answer of the jury is *b*. The checker program will consider your answer correct if .
[ "100\n50\n50\n", "199\n60\n40\n" ]
[ "50\n", "119.4\n" ]
In the first sample the speeds of the impulses are equal, so both of their meetings occur exactly in the middle of the corridor.
[ { "input": "100\n50\n50", "output": "50" }, { "input": "199\n60\n40", "output": "119.4" }, { "input": "1\n1\n1", "output": "0.5" }, { "input": "1\n1\n500", "output": "0.001996007984" }, { "input": "1\n500\n1", "output": "0.998003992" }, { "input": "1\n...
109
0
3
735
298
Sail
[ "brute force", "greedy", "implementation" ]
null
null
The polar bears are going fishing. They plan to sail from (*s**x*,<=*s**y*) to (*e**x*,<=*e**y*). However, the boat can only sail by wind. At each second, the wind blows in one of these directions: east, south, west or north. Assume the boat is currently at (*x*,<=*y*). - If the wind blows to the east, the boat will move to (*x*<=+<=1,<=*y*). - If the wind blows to the south, the boat will move to (*x*,<=*y*<=-<=1). - If the wind blows to the west, the boat will move to (*x*<=-<=1,<=*y*). - If the wind blows to the north, the boat will move to (*x*,<=*y*<=+<=1). Alternatively, they can hold the boat by the anchor. In this case, the boat stays at (*x*,<=*y*). Given the wind direction for *t* seconds, what is the earliest time they sail to (*e**x*,<=*e**y*)?
The first line contains five integers *t*,<=*s**x*,<=*s**y*,<=*e**x*,<=*e**y* (1<=≤<=*t*<=≤<=105,<=<=-<=109<=≤<=*s**x*,<=*s**y*,<=*e**x*,<=*e**y*<=≤<=109). The starting location and the ending location will be different. The second line contains *t* characters, the *i*-th character is the wind blowing direction at the *i*-th second. It will be one of the four possibilities: "E" (east), "S" (south), "W" (west) and "N" (north).
If they can reach (*e**x*,<=*e**y*) within *t* seconds, print the earliest time they can achieve it. Otherwise, print "-1" (without quotes).
[ "5 0 0 1 1\nSESNW\n", "10 5 3 3 6\nNENSWESNEE\n" ]
[ "4\n", "-1\n" ]
In the first sample, they can stay at seconds 1, 3, and move at seconds 2, 4. In the second sample, they cannot sail to the destination.
[ { "input": "5 0 0 1 1\nSESNW", "output": "4" }, { "input": "10 5 3 3 6\nNENSWESNEE", "output": "-1" }, { "input": "19 -172106364 -468680119 -172106365 -468680119\nSSEEESSSESESWSEESSS", "output": "13" }, { "input": "39 -1000000000 -1000000000 -999999997 -1000000000\nENEENWSWSS...
124
307,200
-1
736
435
Pasha Maximizes
[ "greedy" ]
null
null
Pasha has a positive integer *a* without leading zeroes. Today he decided that the number is too small and he should make it larger. Unfortunately, the only operation Pasha can do is to swap two adjacent decimal digits of the integer. Help Pasha count the maximum number he can get if he has the time to make at most *k* swaps.
The single line contains two integers *a* and *k* (1<=≤<=*a*<=≤<=1018; 0<=≤<=*k*<=≤<=100).
Print the maximum number that Pasha can get if he makes at most *k* swaps.
[ "1990 1\n", "300 0\n", "1034 2\n", "9090000078001234 6\n" ]
[ "9190\n", "300\n", "3104\n", "9907000008001234\n" ]
none
[ { "input": "1990 1", "output": "9190" }, { "input": "300 0", "output": "300" }, { "input": "1034 2", "output": "3104" }, { "input": "9090000078001234 6", "output": "9907000008001234" }, { "input": "1234 3", "output": "4123" }, { "input": "5 100", "...
139
2,048,000
-1
738
479
Exams
[ "greedy", "sortings" ]
null
null
Student Valera is an undergraduate student at the University. His end of term exams are approaching and he is to pass exactly *n* exams. Valera is a smart guy, so he will be able to pass any exam he takes on his first try. Besides, he can take several exams on one day, and in any order. According to the schedule, a student can take the exam for the *i*-th subject on the day number *a**i*. However, Valera has made an arrangement with each teacher and the teacher of the *i*-th subject allowed him to take an exam before the schedule time on day *b**i* (*b**i*<=&lt;<=*a**i*). Thus, Valera can take an exam for the *i*-th subject either on day *a**i*, or on day *b**i*. All the teachers put the record of the exam in the student's record book on the day of the actual exam and write down the date of the mark as number *a**i*. Valera believes that it would be rather strange if the entries in the record book did not go in the order of non-decreasing date. Therefore Valera asks you to help him. Find the minimum possible value of the day when Valera can take the final exam if he takes exams so that all the records in his record book go in the order of non-decreasing date.
The first line contains a single positive integer *n* (1<=≤<=*n*<=≤<=5000) — the number of exams Valera will take. Each of the next *n* lines contains two positive space-separated integers *a**i* and *b**i* (1<=≤<=*b**i*<=&lt;<=*a**i*<=≤<=109) — the date of the exam in the schedule and the early date of passing the *i*-th exam, correspondingly.
Print a single integer — the minimum possible number of the day when Valera can take the last exam if he takes all the exams so that all the records in his record book go in the order of non-decreasing date.
[ "3\n5 2\n3 1\n4 2\n", "3\n6 1\n5 2\n4 3\n" ]
[ "2\n", "6\n" ]
In the first sample Valera first takes an exam in the second subject on the first day (the teacher writes down the schedule date that is 3). On the next day he takes an exam in the third subject (the teacher writes down the schedule date, 4), then he takes an exam in the first subject (the teacher writes down the mark with date 5). Thus, Valera takes the last exam on the second day and the dates will go in the non-decreasing order: 3, 4, 5. In the second sample Valera first takes an exam in the third subject on the fourth day. Then he takes an exam in the second subject on the fifth day. After that on the sixth day Valera takes an exam in the first subject.
[ { "input": "3\n5 2\n3 1\n4 2", "output": "2" }, { "input": "3\n6 1\n5 2\n4 3", "output": "6" }, { "input": "1\n1000000000 999999999", "output": "999999999" }, { "input": "1\n2 1", "output": "1" }, { "input": "2\n3 2\n3 2", "output": "2" }, { "input": "...
139
6,451,200
0
739
914
Perfect Squares
[ "brute force", "implementation", "math" ]
null
null
Given an array *a*1,<=*a*2,<=...,<=*a**n* of *n* integers, find the largest number in the array that is not a perfect square. A number *x* is said to be a perfect square if there exists an integer *y* such that *x*<==<=*y*2.
The first line contains a single integer *n* (1<=≤<=*n*<=≤<=1000) — the number of elements in the array. The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (<=-<=106<=≤<=*a**i*<=≤<=106) — the elements of the array. It is guaranteed that at least one element of the array is not a perfect square.
Print the largest number in the array which is not a perfect square. It is guaranteed that an answer always exists.
[ "2\n4 2\n", "8\n1 2 4 8 16 32 64 576\n" ]
[ "2\n", "32\n" ]
In the first sample case, 4 is a perfect square, so the largest number in the array that is not a perfect square is 2.
[ { "input": "2\n4 2", "output": "2" }, { "input": "8\n1 2 4 8 16 32 64 576", "output": "32" }, { "input": "3\n-1 -4 -9", "output": "-1" }, { "input": "5\n918375 169764 598796 76602 538757", "output": "918375" }, { "input": "5\n804610 765625 2916 381050 93025", ...
109
0
0
743
896
Nephren gives a riddle
[ "binary search", "dfs and similar" ]
null
null
Nephren is playing a game with little leprechauns. She gives them an infinite array of strings, *f*0... ∞. *f*0 is "What are you doing at the end of the world? Are you busy? Will you save us?". She wants to let more people know about it, so she defines *f**i*<==<= "What are you doing while sending "*f**i*<=-<=1"? Are you busy? Will you send "*f**i*<=-<=1"?" for all *i*<=≥<=1. For example, *f*1 is "What are you doing while sending "What are you doing at the end of the world? Are you busy? Will you save us?"? Are you busy? Will you send "What are you doing at the end of the world? Are you busy? Will you save us?"?". Note that the quotes in the very beginning and in the very end are for clarity and are not a part of *f*1. It can be seen that the characters in *f**i* are letters, question marks, (possibly) quotation marks and spaces. Nephren will ask the little leprechauns *q* times. Each time she will let them find the *k*-th character of *f**n*. The characters are indexed starting from 1. If *f**n* consists of less than *k* characters, output '.' (without quotes). Can you answer her queries?
The first line contains one integer *q* (1<=≤<=*q*<=≤<=10) — the number of Nephren's questions. Each of the next *q* lines describes Nephren's question and contains two integers *n* and *k* (0<=≤<=*n*<=≤<=105,<=1<=≤<=*k*<=≤<=1018).
One line containing *q* characters. The *i*-th character in it should be the answer for the *i*-th query.
[ "3\n1 1\n1 2\n1 111111111111\n", "5\n0 69\n1 194\n1 139\n0 47\n1 66\n", "10\n4 1825\n3 75\n3 530\n4 1829\n4 1651\n3 187\n4 584\n4 255\n4 774\n2 474\n" ]
[ "Wh.", "abdef", "Areyoubusy" ]
For the first two examples, refer to *f*<sub class="lower-index">0</sub> and *f*<sub class="lower-index">1</sub> given in the legend.
[ { "input": "3\n1 1\n1 2\n1 111111111111", "output": "Wh." }, { "input": "5\n0 69\n1 194\n1 139\n0 47\n1 66", "output": "abdef" }, { "input": "10\n4 1825\n3 75\n3 530\n4 1829\n4 1651\n3 187\n4 584\n4 255\n4 774\n2 474", "output": "Areyoubusy" }, { "input": "1\n0 1", "outpu...
498
5,529,600
3
744
810
Straight <<A>>
[ "implementation", "math" ]
null
null
Noora is a student of one famous high school. It's her final year in school — she is going to study in university next year. However, she has to get an «A» graduation certificate in order to apply to a prestigious one. In school, where Noora is studying, teachers are putting down marks to the online class register, which are integers from 1 to *k*. The worst mark is 1, the best is *k*. Mark that is going to the certificate, is calculated as an average of all the marks, rounded to the closest integer. If several answers are possible, rounding up is produced. For example, 7.3 is rounded to 7, but 7.5 and 7.8784 — to 8. For instance, if Noora has marks [8,<=9], then the mark to the certificate is 9, because the average is equal to 8.5 and rounded to 9, but if the marks are [8,<=8,<=9], Noora will have graduation certificate with 8. To graduate with «A» certificate, Noora has to have mark *k*. Noora got *n* marks in register this year. However, she is afraid that her marks are not enough to get final mark *k*. Noora decided to ask for help in the internet, where hacker Leha immediately responded to her request. He is ready to hack class register for Noora and to add Noora any number of additional marks from 1 to *k*. At the same time, Leha want his hack be unseen to everyone, so he decided to add as less as possible additional marks. Please help Leha to calculate the minimal number of marks he has to add, so that final Noora's mark will become equal to *k*.
The first line contains two integers *n* and *k* (1<=≤<=*n*<=≤<=100,<=1<=≤<=*k*<=≤<=100) denoting the number of marks, received by Noora and the value of highest possible mark. The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=*k*) denoting marks received by Noora before Leha's hack.
Print a single integer — minimal number of additional marks, that Leha has to add in order to change Noora's final mark to *k*.
[ "2 10\n8 9\n", "3 5\n4 4 4\n" ]
[ "4", "3" ]
Consider the first example testcase. Maximal mark is 10, Noora received two marks — 8 and 9, so current final mark is 9. To fix it, Leha can add marks [10, 10, 10, 10] (4 marks in total) to the registry, achieving Noora having average mark equal to <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/1b961585522f76271546da990a6228e7c666277f.png" style="max-width: 100.0%;max-height: 100.0%;"/>. Consequently, new final mark is 10. Less number of marks won't fix the situation. In the second example Leha can add [5, 5, 5] to the registry, so that making average mark equal to 4.5, which is enough to have 5 in the certificate.
[ { "input": "2 10\n8 9", "output": "4" }, { "input": "3 5\n4 4 4", "output": "3" }, { "input": "3 10\n10 8 9", "output": "3" }, { "input": "2 23\n21 23", "output": "2" }, { "input": "5 10\n5 10 10 9 10", "output": "7" }, { "input": "12 50\n18 10 26 22 2...
61
0
0
746
276
Little Girl and Maximum XOR
[ "bitmasks", "dp", "greedy", "implementation", "math" ]
null
null
A little girl loves problems on bitwise operations very much. Here's one of them. You are given two integers *l* and *r*. Let's consider the values of for all pairs of integers *a* and *b* (*l*<=≤<=*a*<=≤<=*b*<=≤<=*r*). Your task is to find the maximum value among all considered ones. Expression means applying bitwise excluding or operation to integers *x* and *y*. The given operation exists in all modern programming languages, for example, in languages *C*++ and *Java* it is represented as "^", in *Pascal* — as "xor".
The single line contains space-separated integers *l* and *r* (1<=≤<=*l*<=≤<=*r*<=≤<=1018). Please, do not use the %lld specifier to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams or the %I64d specifier.
In a single line print a single integer — the maximum value of for all pairs of integers *a*, *b* (*l*<=≤<=*a*<=≤<=*b*<=≤<=*r*).
[ "1 2\n", "8 16\n", "1 1\n" ]
[ "3\n", "31\n", "0\n" ]
none
[ { "input": "1 2", "output": "3" }, { "input": "8 16", "output": "31" }, { "input": "1 1", "output": "0" }, { "input": "506 677", "output": "1023" }, { "input": "33 910", "output": "1023" }, { "input": "36 94", "output": "127" }, { "input": ...
46
102,400
0
747
907
Masha and Bears
[ "brute force", "implementation" ]
null
null
A family consisting of father bear, mother bear and son bear owns three cars. Father bear can climb into the largest car and he likes it. Also, mother bear can climb into the middle car and she likes it. Moreover, son bear can climb into the smallest car and he likes it. It's known that the largest car is strictly larger than the middle car, and the middle car is strictly larger than the smallest car. Masha came to test these cars. She could climb into all cars, but she liked only the smallest car. It's known that a character with size *a* can climb into some car with size *b* if and only if *a*<=≤<=*b*, he or she likes it if and only if he can climb into this car and 2*a*<=≥<=*b*. You are given sizes of bears and Masha. Find out some possible integer non-negative sizes of cars.
You are given four integers *V*1, *V*2, *V*3, *V**m*(1<=≤<=*V**i*<=≤<=100) — sizes of father bear, mother bear, son bear and Masha, respectively. It's guaranteed that *V*1<=&gt;<=*V*2<=&gt;<=*V*3.
Output three integers — sizes of father bear's car, mother bear's car and son bear's car, respectively. If there are multiple possible solutions, print any. If there is no solution, print "-1" (without quotes).
[ "50 30 10 10\n", "100 50 10 21\n" ]
[ "50\n30\n10\n", "-1\n" ]
In first test case all conditions for cars' sizes are satisfied. In second test case there is no answer, because Masha should be able to climb into smallest car (so size of smallest car in not less than 21), but son bear should like it, so maximum possible size of it is 20.
[ { "input": "50 30 10 10", "output": "50\n30\n10" }, { "input": "100 50 10 21", "output": "-1" }, { "input": "100 50 19 10", "output": "100\n50\n19" }, { "input": "99 50 25 49", "output": "100\n99\n49" }, { "input": "3 2 1 1", "output": "4\n3\n1" }, { "...
46
5,529,600
0
749
877
Danil and a Part-time Job
[ "bitmasks", "data structures", "trees" ]
null
null
Danil decided to earn some money, so he had found a part-time job. The interview have went well, so now he is a light switcher. Danil works in a rooted tree (undirected connected acyclic graph) with *n* vertices, vertex 1 is the root of the tree. There is a room in each vertex, light can be switched on or off in each room. Danil's duties include switching light in all rooms of the subtree of the vertex. It means that if light is switched on in some room of the subtree, he should switch it off. Otherwise, he should switch it on. Unfortunately (or fortunately), Danil is very lazy. He knows that his boss is not going to personally check the work. Instead, he will send Danil tasks using Workforces personal messages. There are two types of tasks: 1. pow v describes a task to switch lights in the subtree of vertex *v*.1. get v describes a task to count the number of rooms in the subtree of *v*, in which the light is turned on. Danil should send the answer to his boss using Workforces messages. A subtree of vertex *v* is a set of vertices for which the shortest path from them to the root passes through *v*. In particular, the vertex *v* is in the subtree of *v*. Danil is not going to perform his duties. He asks you to write a program, which answers the boss instead of him.
The first line contains a single integer *n* (1<=≤<=*n*<=≤<=200<=000) — the number of vertices in the tree. The second line contains *n*<=-<=1 space-separated integers *p*2,<=*p*3,<=...,<=*p**n* (1<=≤<=*p**i*<=&lt;<=*i*), where *p**i* is the ancestor of vertex *i*. The third line contains *n* space-separated integers *t*1,<=*t*2,<=...,<=*t**n* (0<=≤<=*t**i*<=≤<=1), where *t**i* is 1, if the light is turned on in vertex *i* and 0 otherwise. The fourth line contains a single integer *q* (1<=≤<=*q*<=≤<=200<=000) — the number of tasks. The next *q* lines are get v or pow v (1<=≤<=*v*<=≤<=*n*) — the tasks described above.
For each task get v print the number of rooms in the subtree of *v*, in which the light is turned on.
[ "4\n1 1 1\n1 0 0 1\n9\nget 1\nget 2\nget 3\nget 4\npow 1\nget 1\nget 2\nget 3\nget 4\n" ]
[ "2\n0\n0\n1\n2\n1\n1\n0\n" ]
<img class="tex-graphics" src="https://espresso.codeforces.com/839c4a0a06cc547ffb8d937bfe52730b51c842b4.png" style="max-width: 100.0%;max-height: 100.0%;"/> The tree after the task pow 1.
[ { "input": "4\n1 1 1\n1 0 0 1\n9\nget 1\nget 2\nget 3\nget 4\npow 1\nget 1\nget 2\nget 3\nget 4", "output": "2\n0\n0\n1\n2\n1\n1\n0" }, { "input": "1\n\n1\n4\npow 1\nget 1\npow 1\nget 1", "output": "0\n1" }, { "input": "10\n1 2 3 4 2 4 1 7 8\n1 1 0 1 1 0 0 0 1 1\n10\npow 1\nget 2\npow 2\...
1,902
63,692,800
3
753
754
Ilya and tic-tac-toe game
[ "brute force", "implementation" ]
null
null
Ilya is an experienced player in tic-tac-toe on the 4<=×<=4 field. He always starts and plays with Xs. He played a lot of games today with his friend Arseny. The friends became tired and didn't finish the last game. It was Ilya's turn in the game when they left it. Determine whether Ilya could have won the game by making single turn or not. The rules of tic-tac-toe on the 4<=×<=4 field are as follows. Before the first turn all the field cells are empty. The two players take turns placing their signs into empty cells (the first player places Xs, the second player places Os). The player who places Xs goes first, the another one goes second. The winner is the player who first gets three of his signs in a row next to each other (horizontal, vertical or diagonal).
The tic-tac-toe position is given in four lines. Each of these lines contains four characters. Each character is '.' (empty cell), 'x' (lowercase English letter x), or 'o' (lowercase English letter o). It is guaranteed that the position is reachable playing tic-tac-toe, and it is Ilya's turn now (in particular, it means that the game is not finished). It is possible that all the cells are empty, it means that the friends left without making single turn.
Print single line: "YES" in case Ilya could have won by making single turn, and "NO" otherwise.
[ "xx..\n.oo.\nx...\noox.\n", "x.ox\nox..\nx.o.\noo.x\n", "x..x\n..oo\no...\nx.xo\n", "o.x.\no...\n.x..\nooxx\n" ]
[ "YES\n", "NO\n", "YES\n", "NO\n" ]
In the first example Ilya had two winning moves: to the empty cell in the left column and to the leftmost empty cell in the first row. In the second example it wasn't possible to win by making single turn. In the third example Ilya could have won by placing X in the last row between two existing Xs. In the fourth example it wasn't possible to win by making single turn.
[ { "input": "xx..\n.oo.\nx...\noox.", "output": "YES" }, { "input": "x.ox\nox..\nx.o.\noo.x", "output": "NO" }, { "input": "x..x\n..oo\no...\nx.xo", "output": "YES" }, { "input": "o.x.\no...\n.x..\nooxx", "output": "NO" }, { "input": ".xox\no.x.\nx.o.\n..o.", "...
46
0
0
754
802
Fake News (easy)
[ "implementation", "strings" ]
null
null
As it's the first of April, Heidi is suspecting that the news she reads today are fake, and she does not want to look silly in front of all the contestants. She knows that a newspiece is fake if it contains heidi as a subsequence. Help Heidi assess whether the given piece is true, but please be discreet about it...
The first and only line of input contains a single nonempty string *s* of length at most 1000 composed of lowercase letters (a-z).
Output YES if the string *s* contains heidi as a subsequence and NO otherwise.
[ "abcheaibcdi\n", "hiedi\n" ]
[ "YES", "NO" ]
A string *s* contains another string *p* as a subsequence if it is possible to delete some characters from *s* and obtain *p*.
[ { "input": "abcheaibcdi", "output": "YES" }, { "input": "hiedi", "output": "NO" }, { "input": "ihied", "output": "NO" }, { "input": "diehi", "output": "NO" }, { "input": "deiih", "output": "NO" }, { "input": "iheid", "output": "NO" }, { "in...
139
20,172,800
3
756
898
Alarm Clock
[ "greedy" ]
null
null
Every evening Vitalya sets *n* alarm clocks to wake up tomorrow. Every alarm clock rings during exactly one minute and is characterized by one integer *a**i* — number of minute after midnight in which it rings. Every alarm clock begins ringing at the beginning of the minute and rings during whole minute. Vitalya will definitely wake up if during some *m* consecutive minutes at least *k* alarm clocks will begin ringing. Pay attention that Vitalya considers only alarm clocks which begin ringing during given period of time. He doesn't consider alarm clocks which started ringing before given period of time and continues ringing during given period of time. Vitalya is so tired that he wants to sleep all day long and not to wake up. Find out minimal number of alarm clocks Vitalya should turn off to sleep all next day. Now all alarm clocks are turned on.
First line contains three integers *n*, *m* and *k* (1<=≤<=*k*<=≤<=*n*<=≤<=2·105, 1<=≤<=*m*<=≤<=106) — number of alarm clocks, and conditions of Vitalya's waking up. Second line contains sequence of distinct integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=106) in which *a**i* equals minute on which *i*-th alarm clock will ring. Numbers are given in arbitrary order. Vitalya lives in a Berland in which day lasts for 106 minutes.
Output minimal number of alarm clocks that Vitalya should turn off to sleep all next day long.
[ "3 3 2\n3 5 1\n", "5 10 3\n12 8 18 25 1\n", "7 7 2\n7 3 4 1 6 5 2\n", "2 2 2\n1 3\n" ]
[ "1\n", "0\n", "6\n", "0\n" ]
In first example Vitalya should turn off first alarm clock which rings at minute 3. In second example Vitalya shouldn't turn off any alarm clock because there are no interval of 10 consequence minutes in which 3 alarm clocks will ring. In third example Vitalya should turn off any 6 alarm clocks.
[ { "input": "3 3 2\n3 5 1", "output": "1" }, { "input": "5 10 3\n12 8 18 25 1", "output": "0" }, { "input": "7 7 2\n7 3 4 1 6 5 2", "output": "6" }, { "input": "2 2 2\n1 3", "output": "0" }, { "input": "1 4 1\n1", "output": "1" }, { "input": "2 3 1\n1 2...
93
2,150,400
-1
757
810
Summer sell-off
[ "greedy", "sortings" ]
null
null
Summer holidays! Someone is going on trips, someone is visiting grandparents, but someone is trying to get a part-time job. This summer Noora decided that she wants to earn some money, and took a job in a shop as an assistant. Shop, where Noora is working, has a plan on the following *n* days. For each day sales manager knows exactly, that in *i*-th day *k**i* products will be put up for sale and exactly *l**i* clients will come to the shop that day. Also, the manager is sure, that everyone, who comes to the shop, buys exactly one product or, if there aren't any left, leaves the shop without buying anything. Moreover, due to the short shelf-life of the products, manager established the following rule: if some part of the products left on the shelves at the end of the day, that products aren't kept on the next day and are sent to the dump. For advertising purposes manager offered to start a sell-out in the shop. He asked Noora to choose any *f* days from *n* next for sell-outs. On each of *f* chosen days the number of products were put up for sale would be doubled. Thus, if on *i*-th day shop planned to put up for sale *k**i* products and Noora has chosen this day for sell-out, shelves of the shop would keep 2·*k**i* products. Consequently, there is an opportunity to sell two times more products on days of sell-out. Noora's task is to choose *f* days to maximize total number of sold products. She asks you to help her with such a difficult problem.
The first line contains two integers *n* and *f* (1<=≤<=*n*<=≤<=105,<=0<=≤<=*f*<=≤<=*n*) denoting the number of days in shop's plan and the number of days that Noora has to choose for sell-out. Each line of the following *n* subsequent lines contains two integers *k**i*,<=*l**i* (0<=≤<=*k**i*,<=*l**i*<=≤<=109) denoting the number of products on the shelves of the shop on the *i*-th day and the number of clients that will come to the shop on *i*-th day.
Print a single integer denoting the maximal number of products that shop can sell.
[ "4 2\n2 1\n3 5\n2 3\n1 5\n", "4 1\n0 2\n0 3\n3 5\n0 6\n" ]
[ "10", "5" ]
In the first example we can choose days with numbers 2 and 4 for sell-out. In this case new numbers of products for sale would be equal to [2, 6, 2, 2] respectively. So on the first day shop will sell 1 product, on the second — 5, on the third — 2, on the fourth — 2. In total 1 + 5 + 2 + 2 = 10 product units. In the second example it is possible to sell 5 products, if you choose third day for sell-out.
[ { "input": "4 2\n2 1\n3 5\n2 3\n1 5", "output": "10" }, { "input": "4 1\n0 2\n0 3\n3 5\n0 6", "output": "5" }, { "input": "1 1\n5 8", "output": "8" }, { "input": "2 1\n8 12\n6 11", "output": "19" }, { "input": "2 1\n6 7\n5 7", "output": "13" }, { "inpu...
46
102,400
0
758
25
Phone numbers
[ "implementation" ]
B. Phone numbers
2
256
Phone number in Berland is a sequence of *n* digits. Often, to make it easier to memorize the number, it is divided into groups of two or three digits. For example, the phone number 1198733 is easier to remember as 11-987-33. Your task is to find for a given phone number any of its divisions into groups of two or three digits.
The first line contains integer *n* (2<=≤<=*n*<=≤<=100) — amount of digits in the phone number. The second line contains *n* digits — the phone number to divide into groups.
Output any of divisions of the given phone number into groups of two or three digits. Separate groups by single character -. If the answer is not unique, output any.
[ "6\n549871\n", "7\n1198733\n" ]
[ "54-98-71", "11-987-33\n" ]
none
[ { "input": "6\n549871", "output": "54-98-71" }, { "input": "7\n1198733", "output": "119-87-33" }, { "input": "2\n74", "output": "74" }, { "input": "2\n33", "output": "33" }, { "input": "3\n074", "output": "074" }, { "input": "3\n081", "output": "08...
92
0
3.977
760
702
Maximum Increase
[ "dp", "greedy", "implementation" ]
null
null
You are given array consisting of *n* integers. Your task is to find the maximum length of an increasing subarray of the given array. A subarray is the sequence of consecutive elements of the array. Subarray is called increasing if each element of this subarray strictly greater than previous.
The first line contains single positive integer *n* (1<=≤<=*n*<=≤<=105) — the number of integers. The second line contains *n* positive integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=109).
Print the maximum length of an increasing subarray of the given array.
[ "5\n1 7 2 11 15\n", "6\n100 100 100 100 100 100\n", "3\n1 2 3\n" ]
[ "3\n", "1\n", "3\n" ]
none
[ { "input": "5\n1 7 2 11 15", "output": "3" }, { "input": "6\n100 100 100 100 100 100", "output": "1" }, { "input": "3\n1 2 3", "output": "3" }, { "input": "1\n1000000000", "output": "1" }, { "input": "10\n802030518 598196518 640274071 983359971 71550121 96204862 7...
31
0
-1
761
352
Jeff and Digits
[ "brute force", "implementation", "math" ]
null
null
Jeff's got *n* cards, each card contains either digit 0, or digit 5. Jeff can choose several cards and put them in a line so that he gets some number. What is the largest possible number divisible by 90 Jeff can make from the cards he's got? Jeff must make the number without leading zero. At that, we assume that number 0 doesn't contain any leading zeroes. Jeff doesn't have to use all the cards.
The first line contains integer *n* (1<=≤<=*n*<=≤<=103). The next line contains *n* integers *a*1, *a*2, ..., *a**n* (*a**i*<==<=0 or *a**i*<==<=5). Number *a**i* represents the digit that is written on the *i*-th card.
In a single line print the answer to the problem — the maximum number, divisible by 90. If you can't make any divisible by 90 number from the cards, print -1.
[ "4\n5 0 5 0\n", "11\n5 5 5 5 5 5 5 5 0 5 5\n" ]
[ "0\n", "5555555550\n" ]
In the first test you can make only one number that is a multiple of 90 — 0. In the second test you can make number 5555555550, it is a multiple of 90.
[ { "input": "4\n5 0 5 0", "output": "0" }, { "input": "11\n5 5 5 5 5 5 5 5 0 5 5", "output": "5555555550" }, { "input": "7\n5 5 5 5 5 5 5", "output": "-1" }, { "input": "1\n5", "output": "-1" }, { "input": "1\n0", "output": "0" }, { "input": "11\n5 0 5 ...
124
0
3
763
849
Odds and Ends
[ "implementation" ]
null
null
Where do odds begin, and where do they end? Where does hope emerge, and will they ever break? Given an integer sequence *a*1,<=*a*2,<=...,<=*a**n* of length *n*. Decide whether it is possible to divide it into an odd number of non-empty subsegments, the each of which has an odd length and begins and ends with odd numbers. A subsegment is a contiguous slice of the whole sequence. For example, {3,<=4,<=5} and {1} are subsegments of sequence {1,<=2,<=3,<=4,<=5,<=6}, while {1,<=2,<=4} and {7} are not.
The first line of input contains a non-negative integer *n* (1<=≤<=*n*<=≤<=100) — the length of the sequence. The second line contains *n* space-separated non-negative integers *a*1,<=*a*2,<=...,<=*a**n* (0<=≤<=*a**i*<=≤<=100) — the elements of the sequence.
Output "Yes" if it's possible to fulfill the requirements, and "No" otherwise. You can output each letter in any case (upper or lower).
[ "3\n1 3 5\n", "5\n1 0 1 5 1\n", "3\n4 3 1\n", "4\n3 9 9 3\n" ]
[ "Yes\n", "Yes\n", "No\n", "No\n" ]
In the first example, divide the sequence into 1 subsegment: {1, 3, 5} and the requirements will be met. In the second example, divide the sequence into 3 subsegments: {1, 0, 1}, {5}, {1}. In the third example, one of the subsegments must start with 4 which is an even number, thus the requirements cannot be met. In the fourth example, the sequence can be divided into 2 subsegments: {3, 9, 9}, {3}, but this is not a valid solution because 2 is an even number.
[ { "input": "3\n1 3 5", "output": "Yes" }, { "input": "5\n1 0 1 5 1", "output": "Yes" }, { "input": "3\n4 3 1", "output": "No" }, { "input": "4\n3 9 9 3", "output": "No" }, { "input": "1\n1", "output": "Yes" }, { "input": "5\n100 99 100 99 99", "out...
61
0
0
765
835
The number on the board
[ "greedy" ]
null
null
Some natural number was written on the board. Its sum of digits was not less than *k*. But you were distracted a bit, and someone changed this number to *n*, replacing some digits with others. It's known that the length of the number didn't change. You have to find the minimum number of digits in which these two numbers can differ.
The first line contains integer *k* (1<=≤<=*k*<=≤<=109). The second line contains integer *n* (1<=≤<=*n*<=&lt;<=10100000). There are no leading zeros in *n*. It's guaranteed that this situation is possible.
Print the minimum number of digits in which the initial number and *n* can differ.
[ "3\n11\n", "3\n99\n" ]
[ "1\n", "0\n" ]
In the first example, the initial number could be 12. In the second example the sum of the digits of *n* is not less than *k*. The initial number could be equal to *n*.
[ { "input": "3\n11", "output": "1" }, { "input": "3\n99", "output": "0" }, { "input": "10\n5205602270", "output": "0" }, { "input": "70\n3326631213", "output": "6" }, { "input": "200\n100000001000000000000000000001000000000000000100000100000000000000000000000000000...
46
0
-1
766
586
Alena's Schedule
[ "implementation" ]
null
null
Alena has successfully passed the entrance exams to the university and is now looking forward to start studying. One two-hour lesson at the Russian university is traditionally called a pair, it lasts for two academic hours (an academic hour is equal to 45 minutes). The University works in such a way that every day it holds exactly *n* lessons. Depending on the schedule of a particular group of students, on a given day, some pairs may actually contain classes, but some may be empty (such pairs are called breaks). The official website of the university has already published the schedule for tomorrow for Alena's group. Thus, for each of the *n* pairs she knows if there will be a class at that time or not. Alena's House is far from the university, so if there are breaks, she doesn't always go home. Alena has time to go home only if the break consists of at least two free pairs in a row, otherwise she waits for the next pair at the university. Of course, Alena does not want to be sleepy during pairs, so she will sleep as long as possible, and will only come to the first pair that is presented in her schedule. Similarly, if there are no more pairs, then Alena immediately goes home. Alena appreciates the time spent at home, so she always goes home when it is possible, and returns to the university only at the beginning of the next pair. Help Alena determine for how many pairs she will stay at the university. Note that during some pairs Alena may be at the university waiting for the upcoming pair.
The first line of the input contains a positive integer *n* (1<=≤<=*n*<=≤<=100) — the number of lessons at the university. The second line contains *n* numbers *a**i* (0<=≤<=*a**i*<=≤<=1). Number *a**i* equals 0, if Alena doesn't have the *i*-th pairs, otherwise it is equal to 1. Numbers *a*1,<=*a*2,<=...,<=*a**n* are separated by spaces.
Print a single number — the number of pairs during which Alena stays at the university.
[ "5\n0 1 0 1 1\n", "7\n1 0 1 0 0 1 0\n", "1\n0\n" ]
[ "4\n", "4\n", "0\n" ]
In the first sample Alena stays at the university from the second to the fifth pair, inclusive, during the third pair she will be it the university waiting for the next pair. In the last sample Alena doesn't have a single pair, so she spends all the time at home.
[ { "input": "5\n0 1 0 1 1", "output": "4" }, { "input": "7\n1 0 1 0 0 1 0", "output": "4" }, { "input": "1\n0", "output": "0" }, { "input": "1\n1", "output": "1" }, { "input": "2\n0 0", "output": "0" }, { "input": "2\n0 1", "output": "1" }, { ...
62
0
3
769
456
Laptops
[ "sortings" ]
null
null
One day Dima and Alex had an argument about the price and quality of laptops. Dima thinks that the more expensive a laptop is, the better it is. Alex disagrees. Alex thinks that there are two laptops, such that the price of the first laptop is less (strictly smaller) than the price of the second laptop but the quality of the first laptop is higher (strictly greater) than the quality of the second laptop. Please, check the guess of Alex. You are given descriptions of *n* laptops. Determine whether two described above laptops exist.
The first line contains an integer *n* (1<=≤<=*n*<=≤<=105) — the number of laptops. Next *n* lines contain two integers each, *a**i* and *b**i* (1<=≤<=*a**i*,<=*b**i*<=≤<=*n*), where *a**i* is the price of the *i*-th laptop, and *b**i* is the number that represents the quality of the *i*-th laptop (the larger the number is, the higher is the quality). All *a**i* are distinct. All *b**i* are distinct.
If Alex is correct, print "Happy Alex", otherwise print "Poor Alex" (without the quotes).
[ "2\n1 2\n2 1\n" ]
[ "Happy Alex\n" ]
none
[ { "input": "2\n1 2\n2 1", "output": "Happy Alex" }, { "input": "2\n1 1\n2 2", "output": "Poor Alex" }, { "input": "3\n2 2\n3 3\n1 1", "output": "Poor Alex" }, { "input": "3\n3 3\n1 2\n2 1", "output": "Happy Alex" }, { "input": "1\n1 1", "output": "Poor Alex" ...
31
0
0
772
761
Dasha and Stairs
[ "brute force", "constructive algorithms", "implementation", "math" ]
null
null
On her way to programming school tiger Dasha faced her first test — a huge staircase! The steps were numbered from one to infinity. As we know, tigers are very fond of all striped things, it is possible that it has something to do with their color. So on some interval of her way she calculated two values — the number of steps with even and odd numbers. You need to check whether there is an interval of steps from the *l*-th to the *r*-th (1<=≤<=*l*<=≤<=*r*), for which values that Dasha has found are correct.
In the only line you are given two integers *a*, *b* (0<=≤<=*a*,<=*b*<=≤<=100) — the number of even and odd steps, accordingly.
In the only line print "YES", if the interval of steps described above exists, and "NO" otherwise.
[ "2 3\n", "3 1\n" ]
[ "YES\n", "NO\n" ]
In the first example one of suitable intervals is from 1 to 5. The interval contains two even steps — 2 and 4, and three odd: 1, 3 and 5.
[ { "input": "2 3", "output": "YES" }, { "input": "3 1", "output": "NO" }, { "input": "5 4", "output": "YES" }, { "input": "9 9", "output": "YES" }, { "input": "85 95", "output": "NO" }, { "input": "0 1", "output": "YES" }, { "input": "89 25"...
93
4,608,000
0
775
327
Flipping Game
[ "brute force", "dp", "implementation" ]
null
null
Iahub got bored, so he invented a game to be played on paper. He writes *n* integers *a*1,<=*a*2,<=...,<=*a**n*. Each of those integers can be either 0 or 1. He's allowed to do exactly one move: he chooses two indices *i* and *j* (1<=≤<=*i*<=≤<=*j*<=≤<=*n*) and flips all values *a**k* for which their positions are in range [*i*,<=*j*] (that is *i*<=≤<=*k*<=≤<=*j*). Flip the value of *x* means to apply operation *x*<==<=1 - *x*. The goal of the game is that after exactly one move to obtain the maximum number of ones. Write a program to solve the little game of Iahub.
The first line of the input contains an integer *n* (1<=≤<=*n*<=≤<=100). In the second line of the input there are *n* integers: *a*1,<=*a*2,<=...,<=*a**n*. It is guaranteed that each of those *n* values is either 0 or 1.
Print an integer — the maximal number of 1s that can be obtained after exactly one move.
[ "5\n1 0 0 1 0\n", "4\n1 0 0 1\n" ]
[ "4\n", "4\n" ]
In the first case, flip the segment from 2 to 5 (*i* = 2, *j* = 5). That flip changes the sequence, it becomes: [1 1 1 0 1]. So, it contains four ones. There is no way to make the whole sequence equal to [1 1 1 1 1]. In the second case, flipping only the second and the third element (*i* = 2, *j* = 3) will turn all numbers into 1.
[ { "input": "5\n1 0 0 1 0", "output": "4" }, { "input": "4\n1 0 0 1", "output": "4" }, { "input": "1\n1", "output": "0" }, { "input": "1\n0", "output": "1" }, { "input": "8\n1 0 0 0 1 0 0 0", "output": "7" }, { "input": "18\n0 0 0 0 0 0 0 0 0 0 0 0 0 0 ...
124
716,800
0
776
716
Crazy Computer
[ "implementation" ]
null
null
ZS the Coder is coding on a crazy computer. If you don't type in a word for a *c* consecutive seconds, everything you typed disappear! More formally, if you typed a word at second *a* and then the next word at second *b*, then if *b*<=-<=*a*<=≤<=*c*, just the new word is appended to other words on the screen. If *b*<=-<=*a*<=&gt;<=*c*, then everything on the screen disappears and after that the word you have typed appears on the screen. For example, if *c*<==<=5 and you typed words at seconds 1,<=3,<=8,<=14,<=19,<=20 then at the second 8 there will be 3 words on the screen. After that, everything disappears at the second 13 because nothing was typed. At the seconds 14 and 19 another two words are typed, and finally, at the second 20, one more word is typed, and a total of 3 words remain on the screen. You're given the times when ZS the Coder typed the words. Determine how many words remain on the screen after he finished typing everything.
The first line contains two integers *n* and *c* (1<=≤<=*n*<=≤<=100<=000,<=1<=≤<=*c*<=≤<=109) — the number of words ZS the Coder typed and the crazy computer delay respectively. The next line contains *n* integers *t*1,<=*t*2,<=...,<=*t**n* (1<=≤<=*t*1<=&lt;<=*t*2<=&lt;<=...<=&lt;<=*t**n*<=≤<=109), where *t**i* denotes the second when ZS the Coder typed the *i*-th word.
Print a single positive integer, the number of words that remain on the screen after all *n* words was typed, in other words, at the second *t**n*.
[ "6 5\n1 3 8 14 19 20\n", "6 1\n1 3 5 7 9 10\n" ]
[ "3", "2" ]
The first sample is already explained in the problem statement. For the second sample, after typing the first word at the second 1, it disappears because the next word is typed at the second 3 and 3 - 1 &gt; 1. Similarly, only 1 word will remain at the second 9. Then, a word is typed at the second 10, so there will be two words on the screen, as the old word won't disappear because 10 - 9 ≤ 1.
[ { "input": "6 5\n1 3 8 14 19 20", "output": "3" }, { "input": "6 1\n1 3 5 7 9 10", "output": "2" }, { "input": "1 1\n1000000000", "output": "1" }, { "input": "5 5\n1 7 12 13 14", "output": "4" }, { "input": "2 1000000000\n1 1000000000", "output": "2" }, { ...
155
8,601,600
3
777
367
Sereja and Algorithm
[ "data structures", "implementation" ]
null
null
Sereja loves all sorts of algorithms. He has recently come up with a new algorithm, which receives a string as an input. Let's represent the input string of the algorithm as *q*<==<=*q*1*q*2... *q**k*. The algorithm consists of two steps: 1. Find any continuous subsequence (substring) of three characters of string *q*, which doesn't equal to either string "zyx", "xzy", "yxz". If *q* doesn't contain any such subsequence, terminate the algorithm, otherwise go to step 2. 1. Rearrange the letters of the found subsequence randomly and go to step 1. Sereja thinks that the algorithm works correctly on string *q* if there is a non-zero probability that the algorithm will be terminated. But if the algorithm anyway will work for infinitely long on a string, then we consider the algorithm to work incorrectly on this string. Sereja wants to test his algorithm. For that, he has string *s*<==<=*s*1*s*2... *s**n*, consisting of *n* characters. The boy conducts a series of *m* tests. As the *i*-th test, he sends substring *s**l**i**s**l**i*<=+<=1... *s**r**i* (1<=≤<=*l**i*<=≤<=*r**i*<=≤<=*n*) to the algorithm input. Unfortunately, the implementation of his algorithm works too long, so Sereja asked you to help. For each test (*l**i*,<=*r**i*) determine if the algorithm works correctly on this test or not.
The first line contains non-empty string *s*, its length (*n*) doesn't exceed 105. It is guaranteed that string *s* only contains characters: 'x', 'y', 'z'. The second line contains integer *m* (1<=≤<=*m*<=≤<=105) — the number of tests. Next *m* lines contain the tests. The *i*-th line contains a pair of integers *l**i*, *r**i* (1<=≤<=*l**i*<=≤<=*r**i*<=≤<=*n*).
For each test, print "YES" (without the quotes) if the algorithm works correctly on the corresponding test and "NO" (without the quotes) otherwise.
[ "zyxxxxxxyyz\n5\n5 5\n1 3\n1 11\n1 4\n3 6\n" ]
[ "YES\nYES\nNO\nYES\nNO\n" ]
In the first example, in test one and two the algorithm will always be terminated in one step. In the fourth test you can get string "xzyx" on which the algorithm will terminate. In all other tests the algorithm doesn't work correctly.
[ { "input": "zyxxxxxxyyz\n5\n5 5\n1 3\n1 11\n1 4\n3 6", "output": "YES\nYES\nNO\nYES\nNO" }, { "input": "yxzyzxzzxyyzzxxxzyyzzyzxxzxyzyyzxyzxyxxyzxyxzyzxyzxyyxzzzyzxyyxyzxxy\n10\n17 67\n6 35\n12 45\n56 56\n14 30\n25 54\n1 1\n46 54\n3 33\n19 40", "output": "NO\nNO\nNO\nYES\nYES\nNO\nYES\nNO\nNO\nY...
46
0
0
779
431
Black Square
[ "implementation" ]
null
null
Quite recently, a very smart student named Jury decided that lectures are boring, so he downloaded a game called "Black Square" on his super cool touchscreen phone. In this game, the phone's screen is divided into four vertical strips. Each second, a black square appears on some of the strips. According to the rules of the game, Jury must use this second to touch the corresponding strip to make the square go away. As Jury is both smart and lazy, he counted that he wastes exactly *a**i* calories on touching the *i*-th strip. You've got a string *s*, describing the process of the game and numbers *a*1,<=*a*2,<=*a*3,<=*a*4. Calculate how many calories Jury needs to destroy all the squares?
The first line contains four space-separated integers *a*1, *a*2, *a*3, *a*4 (0<=≤<=*a*1,<=*a*2,<=*a*3,<=*a*4<=≤<=104). The second line contains string *s* (1<=≤<=|*s*|<=≤<=105), where the *і*-th character of the string equals "1", if on the *i*-th second of the game the square appears on the first strip, "2", if it appears on the second strip, "3", if it appears on the third strip, "4", if it appears on the fourth strip.
Print a single integer — the total number of calories that Jury wastes.
[ "1 2 3 4\n123214\n", "1 5 3 2\n11221\n" ]
[ "13\n", "13\n" ]
none
[ { "input": "1 2 3 4\n123214", "output": "13" }, { "input": "1 5 3 2\n11221", "output": "13" }, { "input": "5 5 5 1\n3422", "output": "16" }, { "input": "4 3 2 1\n2", "output": "3" }, { "input": "5651 6882 6954 4733\n2442313421", "output": "60055" }, { ...
77
0
3
781
189
Cut Ribbon
[ "brute force", "dp" ]
null
null
Polycarpus has a ribbon, its length is *n*. He wants to cut the ribbon in a way that fulfils the following two conditions: - After the cutting each ribbon piece should have length *a*, *b* or *c*. - After the cutting the number of ribbon pieces should be maximum. Help Polycarpus and find the number of ribbon pieces after the required cutting.
The first line contains four space-separated integers *n*, *a*, *b* and *c* (1<=≤<=*n*,<=*a*,<=*b*,<=*c*<=≤<=4000) — the length of the original ribbon and the acceptable lengths of the ribbon pieces after the cutting, correspondingly. The numbers *a*, *b* and *c* can coincide.
Print a single number — the maximum possible number of ribbon pieces. It is guaranteed that at least one correct ribbon cutting exists.
[ "5 5 3 2\n", "7 5 5 2\n" ]
[ "2\n", "2\n" ]
In the first example Polycarpus can cut the ribbon in such way: the first piece has length 2, the second piece has length 3. In the second example Polycarpus can cut the ribbon in such way: the first piece has length 5, the second piece has length 2.
[ { "input": "5 5 3 2", "output": "2" }, { "input": "7 5 5 2", "output": "2" }, { "input": "4 4 4 4", "output": "1" }, { "input": "1 1 1 1", "output": "1" }, { "input": "4000 1 2 3", "output": "4000" }, { "input": "4000 3 4 5", "output": "1333" }, ...
31
0
0
782
626
Simple Skewness
[ "binary search", "math", "ternary search" ]
null
null
Define the simple skewness of a collection of numbers to be the collection's mean minus its median. You are given a list of *n* (not necessarily distinct) integers. Find the non-empty subset (with repetition) with the maximum simple skewness. The mean of a collection is the average of its elements. The median of a collection is its middle element when all of its elements are sorted, or the average of its two middle elements if it has even size.
The first line of the input contains a single integer *n* (1<=≤<=*n*<=≤<=200 000) — the number of elements in the list. The second line contains *n* integers *x**i* (0<=≤<=*x**i*<=≤<=1<=000<=000) — the *i*th element of the list.
In the first line, print a single integer *k* — the size of the subset. In the second line, print *k* integers — the elements of the subset in any order. If there are multiple optimal subsets, print any.
[ "4\n1 2 3 12\n", "4\n1 1 2 2\n", "2\n1 2\n" ]
[ "3\n1 2 12 \n", "3\n1 1 2 \n", "2\n1 2\n" ]
In the first case, the optimal subset is <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/04cdbd07a0375de9c557422eca077386392a9349.png" style="max-width: 100.0%;max-height: 100.0%;"/>, which has mean 5, median 2, and simple skewness of 5 - 2 = 3. In the second case, the optimal subset is <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/af49670de7c27def20edf0ec421d9bb17d904c94.png" style="max-width: 100.0%;max-height: 100.0%;"/>. Note that repetition is allowed. In the last case, any subset has the same median and mean, so all have simple skewness of 0.
[ { "input": "4\n1 2 3 12", "output": "3\n1 2 12 " }, { "input": "4\n1 1 2 2", "output": "3\n1 1 2 " }, { "input": "2\n1 2", "output": "2\n1 2" }, { "input": "1\n1000000", "output": "1\n1000000 " }, { "input": "20\n999999 999998 999996 999992 999984 999968 999936 99...
186
30,515,200
0
784
808
Lucky Year
[ "implementation" ]
null
null
Apart from having lots of holidays throughout the year, residents of Berland also have whole lucky years. Year is considered lucky if it has no more than 1 non-zero digit in its number. So years 100, 40000, 5 are lucky and 12, 3001 and 12345 are not. You are given current year in Berland. Your task is to find how long will residents of Berland wait till the next lucky year.
The first line contains integer number *n* (1<=≤<=*n*<=≤<=109) — current year in Berland.
Output amount of years from the current year to the next lucky one.
[ "4\n", "201\n", "4000\n" ]
[ "1\n", "99\n", "1000\n" ]
In the first example next lucky year is 5. In the second one — 300. In the third — 5000.
[ { "input": "4", "output": "1" }, { "input": "201", "output": "99" }, { "input": "4000", "output": "1000" }, { "input": "9", "output": "1" }, { "input": "10", "output": "10" }, { "input": "1", "output": "1" }, { "input": "100000000", "ou...
46
0
3
785
349
Cinema Line
[ "greedy", "implementation" ]
null
null
The new "Die Hard" movie has just been released! There are *n* people at the cinema box office standing in a huge line. Each of them has a single 100, 50 or 25 ruble bill. A "Die Hard" ticket costs 25 rubles. Can the booking clerk sell a ticket to each person and give the change if he initially has no money and sells the tickets strictly in the order people follow in the line?
The first line contains integer *n* (1<=≤<=*n*<=≤<=105) — the number of people in the line. The next line contains *n* integers, each of them equals 25, 50 or 100 — the values of the bills the people have. The numbers are given in the order from the beginning of the line (at the box office) to the end of the line.
Print "YES" (without the quotes) if the booking clerk can sell a ticket to each person and give the change. Otherwise print "NO".
[ "4\n25 25 50 50\n", "2\n25 100\n", "4\n50 50 25 25\n" ]
[ "YES\n", "NO\n", "NO\n" ]
none
[ { "input": "4\n25 25 50 50", "output": "YES" }, { "input": "2\n25 100", "output": "NO" }, { "input": "4\n50 50 25 25", "output": "NO" }, { "input": "3\n25 50 100", "output": "NO" }, { "input": "10\n25 25 25 25 25 25 25 25 25 25", "output": "YES" }, { "...
342
7,782,400
0
788
868
Qualification Rounds
[ "bitmasks", "brute force", "constructive algorithms", "dp" ]
null
null
Snark and Philip are preparing the problemset for the upcoming pre-qualification round for semi-quarter-finals. They have a bank of *n* problems, and they want to select any non-empty subset of it as a problemset. *k* experienced teams are participating in the contest. Some of these teams already know some of the problems. To make the contest interesting for them, each of the teams should know at most half of the selected problems. Determine if Snark and Philip can make an interesting problemset!
The first line contains two integers *n*, *k* (1<=≤<=*n*<=≤<=105, 1<=≤<=*k*<=≤<=4) — the number of problems and the number of experienced teams. Each of the next *n* lines contains *k* integers, each equal to 0 or 1. The *j*-th number in the *i*-th line is 1 if *j*-th team knows *i*-th problem and 0 otherwise.
Print "YES" (quotes for clarity), if it is possible to make an interesting problemset, and "NO" otherwise. You can print each character either upper- or lowercase ("YeS" and "yes" are valid when the answer is "YES").
[ "5 3\n1 0 1\n1 1 0\n1 0 0\n1 0 0\n1 0 0\n", "3 2\n1 0\n1 1\n0 1\n" ]
[ "NO\n", "YES\n" ]
In the first example you can't make any interesting problemset, because the first team knows all problems. In the second example you can choose the first and the third problems.
[ { "input": "5 3\n1 0 1\n1 1 0\n1 0 0\n1 0 0\n1 0 0", "output": "NO" }, { "input": "3 2\n1 0\n1 1\n0 1", "output": "YES" }, { "input": "10 2\n1 0\n1 0\n0 0\n1 1\n0 0\n1 1\n0 0\n1 1\n0 1\n0 1", "output": "YES" }, { "input": "10 3\n1 0 0\n0 1 1\n1 0 0\n0 1 0\n0 0 1\n1 0 1\n0 1 1...
0
0
-1
791
926
Add Points
[]
null
null
There are *n* points on a straight line, and the *i*-th point among them is located at *x**i*. All these coordinates are distinct. Determine the number *m* — the smallest number of points you should add on the line to make the distances between all neighboring points equal.
The first line contains a single integer *n* (3<=≤<=*n*<=≤<=100<=000) — the number of points. The second line contains a sequence of integers *x*1,<=*x*2,<=...,<=*x**n* (<=-<=109<=≤<=*x**i*<=≤<=109) — the coordinates of the points. All these coordinates are distinct. The points can be given in an arbitrary order.
Print a single integer *m* — the smallest number of points you should add on the line to make the distances between all neighboring points equal.
[ "3\n-5 10 5\n", "6\n100 200 400 300 600 500\n", "4\n10 9 0 -1\n" ]
[ "1\n", "0\n", "8\n" ]
In the first example you can add one point with coordinate 0. In the second example the distances between all neighboring points are already equal, so you shouldn't add anything.
[ { "input": "3\n-5 10 5", "output": "1" }, { "input": "6\n100 200 400 300 600 500", "output": "0" }, { "input": "4\n10 9 0 -1", "output": "8" }, { "input": "3\n1 4 7", "output": "0" }, { "input": "3\n1 4 6", "output": "3" }, { "input": "3\n1 2 6", "...
296
15,769,600
3
794
863
Kayaking
[ "brute force", "greedy", "sortings" ]
null
null
Vadim is really keen on travelling. Recently he heard about kayaking activity near his town and became very excited about it, so he joined a party of kayakers. Now the party is ready to start its journey, but firstly they have to choose kayaks. There are 2·*n* people in the group (including Vadim), and they have exactly *n*<=-<=1 tandem kayaks (each of which, obviously, can carry two people) and 2 single kayaks. *i*-th person's weight is *w**i*, and weight is an important matter in kayaking — if the difference between the weights of two people that sit in the same tandem kayak is too large, then it can crash. And, of course, people want to distribute their seats in kayaks in order to minimize the chances that kayaks will crash. Formally, the instability of a single kayak is always 0, and the instability of a tandem kayak is the absolute difference between weights of the people that are in this kayak. Instability of the whole journey is the total instability of all kayaks. Help the party to determine minimum possible total instability!
The first line contains one number *n* (2<=≤<=*n*<=≤<=50). The second line contains 2·*n* integer numbers *w*1, *w*2, ..., *w*2*n*, where *w**i* is weight of person *i* (1<=≤<=*w**i*<=≤<=1000).
Print minimum possible total instability.
[ "2\n1 2 3 4\n", "4\n1 3 4 6 3 4 100 200\n" ]
[ "1\n", "5\n" ]
none
[ { "input": "2\n1 2 3 4", "output": "1" }, { "input": "4\n1 3 4 6 3 4 100 200", "output": "5" }, { "input": "3\n305 139 205 406 530 206", "output": "102" }, { "input": "3\n610 750 778 6 361 407", "output": "74" }, { "input": "5\n97 166 126 164 154 98 221 7 51 47", ...
62
1,536,000
0
797
675
Infinite Sequence
[ "math" ]
null
null
Vasya likes everything infinite. Now he is studying the properties of a sequence *s*, such that its first element is equal to *a* (*s*1<==<=*a*), and the difference between any two neighbouring elements is equal to *c* (*s**i*<=-<=*s**i*<=-<=1<==<=*c*). In particular, Vasya wonders if his favourite integer *b* appears in this sequence, that is, there exists a positive integer *i*, such that *s**i*<==<=*b*. Of course, you are the person he asks for a help.
The first line of the input contain three integers *a*, *b* and *c* (<=-<=109<=≤<=*a*,<=*b*,<=*c*<=≤<=109) — the first element of the sequence, Vasya's favorite number and the difference between any two neighbouring elements of the sequence, respectively.
If *b* appears in the sequence *s* print "YES" (without quotes), otherwise print "NO" (without quotes).
[ "1 7 3\n", "10 10 0\n", "1 -4 5\n", "0 60 50\n" ]
[ "YES\n", "YES\n", "NO\n", "NO\n" ]
In the first sample, the sequence starts from integers 1, 4, 7, so 7 is its element. In the second sample, the favorite integer of Vasya is equal to the first element of the sequence. In the third sample all elements of the sequence are greater than Vasya's favorite integer. In the fourth sample, the sequence starts from 0, 50, 100, and all the following elements are greater than Vasya's favorite integer.
[ { "input": "1 7 3", "output": "YES" }, { "input": "10 10 0", "output": "YES" }, { "input": "1 -4 5", "output": "NO" }, { "input": "0 60 50", "output": "NO" }, { "input": "1 -4 -5", "output": "YES" }, { "input": "0 1 0", "output": "NO" }, { ...
1,000
5,632,000
0
798
1,005
Delete from the Left
[ "brute force", "implementation", "strings" ]
null
null
You are given two strings $s$ and $t$. In a single move, you can choose any of two strings and delete the first (that is, the leftmost) character. After a move, the length of the string decreases by $1$. You can't choose a string if it is empty. For example: - by applying a move to the string "where", the result is the string "here", - by applying a move to the string "a", the result is an empty string "". You are required to make two given strings equal using the fewest number of moves. It is possible that, in the end, both strings will be equal to the empty string, and so, are equal to each other. In this case, the answer is obviously the sum of the lengths of the initial strings. Write a program that finds the minimum number of moves to make two given strings $s$ and $t$ equal.
The first line of the input contains $s$. In the second line of the input contains $t$. Both strings consist only of lowercase Latin letters. The number of letters in each string is between 1 and $2\cdot10^5$, inclusive.
Output the fewest number of moves required. It is possible that, in the end, both strings will be equal to the empty string, and so, are equal to each other. In this case, the answer is obviously the sum of the lengths of the given strings.
[ "test\nwest\n", "codeforces\nyes\n", "test\nyes\n", "b\nab\n" ]
[ "2\n", "9\n", "7\n", "1\n" ]
In the first example, you should apply the move once to the first string and apply the move once to the second string. As a result, both strings will be equal to "est". In the second example, the move should be applied to the string "codeforces" $8$ times. As a result, the string becomes "codeforces" $\to$ "es". The move should be applied to the string "yes" once. The result is the same string "yes" $\to$ "es". In the third example, you can make the strings equal only by completely deleting them. That is, in the end, both strings will be empty. In the fourth example, the first character of the second string should be deleted.
[ { "input": "test\nwest", "output": "2" }, { "input": "codeforces\nyes", "output": "9" }, { "input": "test\nyes", "output": "7" }, { "input": "b\nab", "output": "1" }, { "input": "z\nz", "output": "0" }, { "input": "abacabadabacaba\nabacabadacaba", ...
93
4,096,000
3
801
239
Two Bags of Potatoes
[ "greedy", "implementation", "math" ]
null
null
Valera had two bags of potatoes, the first of these bags contains *x* (*x*<=≥<=1) potatoes, and the second — *y* (*y*<=≥<=1) potatoes. Valera — very scattered boy, so the first bag of potatoes (it contains *x* potatoes) Valera lost. Valera remembers that the total amount of potatoes (*x*<=+<=*y*) in the two bags, firstly, was not gerater than *n*, and, secondly, was divisible by *k*. Help Valera to determine how many potatoes could be in the first bag. Print all such possible numbers in ascending order.
The first line of input contains three integers *y*, *k*, *n* (1<=≤<=*y*,<=*k*,<=*n*<=≤<=109; <=≤<=105).
Print the list of whitespace-separated integers — all possible values of *x* in ascending order. You should print each possible value of *x* exactly once. If there are no such values of *x* print a single integer -1.
[ "10 1 10\n", "10 6 40\n" ]
[ "-1\n", "2 8 14 20 26 \n" ]
none
[ { "input": "10 1 10", "output": "-1" }, { "input": "10 6 40", "output": "2 8 14 20 26 " }, { "input": "10 1 20", "output": "1 2 3 4 5 6 7 8 9 10 " }, { "input": "1 10000 1000000000", "output": "9999 19999 29999 39999 49999 59999 69999 79999 89999 99999 109999 119999 12999...
1,000
0
0
804
507
Amr and Pins
[ "geometry", "math" ]
null
null
Amr loves Geometry. One day he came up with a very interesting problem. Amr has a circle of radius *r* and center in point (*x*,<=*y*). He wants the circle center to be in new position (*x*',<=*y*'). In one step Amr can put a pin to the border of the circle in a certain point, then rotate the circle around that pin by any angle and finally remove the pin. Help Amr to achieve his goal in minimum number of steps.
Input consists of 5 space-separated integers *r*, *x*, *y*, *x*' *y*' (1<=≤<=*r*<=≤<=105, <=-<=105<=≤<=*x*,<=*y*,<=*x*',<=*y*'<=≤<=105), circle radius, coordinates of original center of the circle and coordinates of destination center of the circle respectively.
Output a single integer — minimum number of steps required to move the center of the circle to the destination point.
[ "2 0 0 0 4\n", "1 1 1 4 4\n", "4 5 6 5 6\n" ]
[ "1\n", "3\n", "0\n" ]
In the first sample test the optimal way is to put a pin at point (0, 2) and rotate the circle by 180 degrees counter-clockwise (or clockwise, no matter). <img class="tex-graphics" src="https://espresso.codeforces.com/4e40fd4cc24a2050a0488aa131e6244369328039.png" style="max-width: 100.0%;max-height: 100.0%;"/>
[ { "input": "2 0 0 0 4", "output": "1" }, { "input": "1 1 1 4 4", "output": "3" }, { "input": "4 5 6 5 6", "output": "0" }, { "input": "10 20 0 40 0", "output": "1" }, { "input": "9 20 0 40 0", "output": "2" }, { "input": "5 -1 -6 -5 1", "output": "...
109
0
3
806
597
Divisibility
[ "math" ]
null
null
Find the number of *k*-divisible numbers on the segment [*a*,<=*b*]. In other words you need to find the number of such integer values *x* that *a*<=≤<=*x*<=≤<=*b* and *x* is divisible by *k*.
The only line contains three space-separated integers *k*, *a* and *b* (1<=≤<=*k*<=≤<=1018;<=-<=1018<=≤<=*a*<=≤<=*b*<=≤<=1018).
Print the required number.
[ "1 1 10\n", "2 -4 4\n" ]
[ "10\n", "5\n" ]
none
[ { "input": "1 1 10", "output": "10" }, { "input": "2 -4 4", "output": "5" }, { "input": "1 1 1", "output": "1" }, { "input": "1 0 0", "output": "1" }, { "input": "1 0 1", "output": "2" }, { "input": "1 10181 10182", "output": "2" }, { "inpu...
140
0
0
809
208
Dubstep
[ "strings" ]
null
null
Vasya works as a DJ in the best Berland nightclub, and he often uses dubstep music in his performance. Recently, he has decided to take a couple of old songs and make dubstep remixes from them. Let's assume that a song consists of some number of words. To make the dubstep remix of this song, Vasya inserts a certain number of words "WUB" before the first word of the song (the number may be zero), after the last word (the number may be zero), and between words (at least one between any pair of neighbouring words), and then the boy glues together all the words, including "WUB", in one string and plays the song at the club. For example, a song with words "I AM X" can transform into a dubstep remix as "WUBWUBIWUBAMWUBWUBX" and cannot transform into "WUBWUBIAMWUBX". Recently, Petya has heard Vasya's new dubstep track, but since he isn't into modern music, he decided to find out what was the initial song that Vasya remixed. Help Petya restore the original song.
The input consists of a single non-empty string, consisting only of uppercase English letters, the string's length doesn't exceed 200 characters. It is guaranteed that before Vasya remixed the song, no word contained substring "WUB" in it; Vasya didn't change the word order. It is also guaranteed that initially the song had at least one word.
Print the words of the initial song that Vasya used to make a dubsteb remix. Separate the words with a space.
[ "WUBWUBABCWUB\n", "WUBWEWUBAREWUBWUBTHEWUBCHAMPIONSWUBMYWUBFRIENDWUB\n" ]
[ "ABC ", "WE ARE THE CHAMPIONS MY FRIEND " ]
In the first sample: "WUBWUBABCWUB" = "WUB" + "WUB" + "ABC" + "WUB". That means that the song originally consisted of a single word "ABC", and all words "WUB" were added by Vasya. In the second sample Vasya added a single word "WUB" between all neighbouring words, in the beginning and in the end, except for words "ARE" and "THE" — between them Vasya added two "WUB".
[ { "input": "WUBWUBABCWUB", "output": "ABC " }, { "input": "WUBWEWUBAREWUBWUBTHEWUBCHAMPIONSWUBMYWUBFRIENDWUB", "output": "WE ARE THE CHAMPIONS MY FRIEND " }, { "input": "WUBWUBWUBSR", "output": "SR " }, { "input": "RWUBWUBWUBLWUB", "output": "R L " }, { "input": "...
124
0
3
813
264
Escape from Stones
[ "constructive algorithms", "data structures", "implementation", "two pointers" ]
null
null
Squirrel Liss lived in a forest peacefully, but unexpected trouble happens. Stones fall from a mountain. Initially Squirrel Liss occupies an interval [0,<=1]. Next, *n* stones will fall and Liss will escape from the stones. The stones are numbered from 1 to *n* in order. The stones always fall to the center of Liss's interval. When Liss occupies the interval [*k*<=-<=*d*,<=*k*<=+<=*d*] and a stone falls to *k*, she will escape to the left or to the right. If she escapes to the left, her new interval will be [*k*<=-<=*d*,<=*k*]. If she escapes to the right, her new interval will be [*k*,<=*k*<=+<=*d*]. You are given a string *s* of length *n*. If the *i*-th character of *s* is "l" or "r", when the *i*-th stone falls Liss will escape to the left or to the right, respectively. Find the sequence of stones' numbers from left to right after all the *n* stones falls.
The input consists of only one line. The only line contains the string *s* (1<=≤<=|*s*|<=≤<=106). Each character in *s* will be either "l" or "r".
Output *n* lines — on the *i*-th line you should print the *i*-th stone's number from the left.
[ "llrlr\n", "rrlll\n", "lrlrr\n" ]
[ "3\n5\n4\n2\n1\n", "1\n2\n5\n4\n3\n", "2\n4\n5\n3\n1\n" ]
In the first example, the positions of stones 1, 2, 3, 4, 5 will be <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/58fdb5684df807bfcb705a9da9ce175613362b7d.png" style="max-width: 100.0%;max-height: 100.0%;"/>, respectively. So you should print the sequence: 3, 5, 4, 2, 1.
[ { "input": "llrlr", "output": "3\n5\n4\n2\n1" }, { "input": "rrlll", "output": "1\n2\n5\n4\n3" }, { "input": "lrlrr", "output": "2\n4\n5\n3\n1" }, { "input": "lllrlrllrl", "output": "4\n6\n9\n10\n8\n7\n5\n3\n2\n1" }, { "input": "llrlrrrlrr", "output": "3\n5\n6...
452
45,977,600
3
819
978
Letters
[ "binary search", "implementation", "two pointers" ]
null
null
There are $n$ dormitories in Berland State University, they are numbered with integers from $1$ to $n$. Each dormitory consists of rooms, there are $a_i$ rooms in $i$-th dormitory. The rooms in $i$-th dormitory are numbered from $1$ to $a_i$. A postman delivers letters. Sometimes there is no specific dormitory and room number in it on an envelope. Instead of it only a room number among all rooms of all $n$ dormitories is written on an envelope. In this case, assume that all the rooms are numbered from $1$ to $a_1 + a_2 + \dots + a_n$ and the rooms of the first dormitory go first, the rooms of the second dormitory go after them and so on. For example, in case $n=2$, $a_1=3$ and $a_2=5$ an envelope can have any integer from $1$ to $8$ written on it. If the number $7$ is written on an envelope, it means that the letter should be delivered to the room number $4$ of the second dormitory. For each of $m$ letters by the room number among all $n$ dormitories, determine the particular dormitory and the room number in a dormitory where this letter should be delivered.
The first line contains two integers $n$ and $m$ $(1 \le n, m \le 2 \cdot 10^{5})$ — the number of dormitories and the number of letters. The second line contains a sequence $a_1, a_2, \dots, a_n$ $(1 \le a_i \le 10^{10})$, where $a_i$ equals to the number of rooms in the $i$-th dormitory. The third line contains a sequence $b_1, b_2, \dots, b_m$ $(1 \le b_j \le a_1 + a_2 + \dots + a_n)$, where $b_j$ equals to the room number (among all rooms of all dormitories) for the $j$-th letter. All $b_j$ are given in increasing order.
Print $m$ lines. For each letter print two integers $f$ and $k$ — the dormitory number $f$ $(1 \le f \le n)$ and the room number $k$ in this dormitory $(1 \le k \le a_f)$ to deliver the letter.
[ "3 6\n10 15 12\n1 9 12 23 26 37\n", "2 3\n5 10000000000\n5 6 9999999999\n" ]
[ "1 1\n1 9\n2 2\n2 13\n3 1\n3 12\n", "1 5\n2 1\n2 9999999994\n" ]
In the first example letters should be delivered in the following order: - the first letter in room $1$ of the first dormitory - the second letter in room $9$ of the first dormitory - the third letter in room $2$ of the second dormitory - the fourth letter in room $13$ of the second dormitory - the fifth letter in room $1$ of the third dormitory - the sixth letter in room $12$ of the third dormitory
[ { "input": "3 6\n10 15 12\n1 9 12 23 26 37", "output": "1 1\n1 9\n2 2\n2 13\n3 1\n3 12" }, { "input": "2 3\n5 10000000000\n5 6 9999999999", "output": "1 5\n2 1\n2 9999999994" }, { "input": "1 1\n1\n1", "output": "1 1" }, { "input": "5 15\n10 20 30 20 10\n1 6 10 11 15 30 31 54...
77
0
0
820
297
Fish Weight
[ "constructive algorithms", "greedy" ]
null
null
It is known that there are *k* fish species in the polar ocean, numbered from 1 to *k*. They are sorted by non-decreasing order of their weight, which is a positive number. Let the weight of the *i*-th type of fish be *w**i*, then 0<=&lt;<=*w*1<=≤<=*w*2<=≤<=...<=≤<=*w**k* holds. Polar bears Alice and Bob each have caught some fish, and they are guessing who has the larger sum of weight of the fish he/she's caught. Given the type of the fish they've caught, determine whether it is possible that the fish caught by Alice has a strictly larger total weight than Bob's. In other words, does there exist a sequence of weights *w**i* (not necessary integers), such that the fish caught by Alice has a strictly larger total weight?
The first line contains three integers *n*,<=*m*,<=*k* (1<=≤<=*n*,<=*m*<=≤<=105,<=1<=≤<=*k*<=≤<=109) — the number of fish caught by Alice and Bob respectively, and the number of fish species. The second line contains *n* integers each from 1 to *k*, the list of fish type caught by Alice. The third line contains *m* integers each from 1 to *k*, the list of fish type caught by Bob. Note that one may have caught more than one fish for a same species.
Output "YES" (without quotes) if it is possible, and "NO" (without quotes) otherwise.
[ "3 3 3\n2 2 2\n1 1 3\n", "4 7 9\n5 2 7 3\n3 5 2 7 3 8 7\n" ]
[ "YES\n", "NO\n" ]
In the first sample, if *w*<sub class="lower-index">1</sub> = 1, *w*<sub class="lower-index">2</sub> = 2, *w*<sub class="lower-index">3</sub> = 2.5, then Alice has a total of 2 + 2 + 2 = 6 weight units, while Bob only has 1 + 1 + 2.5 = 4.5. In the second sample, the fish that Alice caught is a subset of Bob's. Therefore, the total weight of Bob’s fish is always not less than the total weight of Alice’s fish.
[ { "input": "3 3 3\n2 2 2\n1 1 3", "output": "YES" }, { "input": "4 7 9\n5 2 7 3\n3 5 2 7 3 8 7", "output": "NO" }, { "input": "5 5 10\n8 2 8 5 9\n9 1 7 5 1", "output": "YES" }, { "input": "7 7 10\n8 2 8 10 6 9 10\n2 4 9 5 6 2 5", "output": "YES" }, { "input": "15 ...
124
5,734,400
-1
821
78
Easter Eggs
[ "constructive algorithms", "implementation" ]
B. Easter Eggs
2
256
The Easter Rabbit laid *n* eggs in a circle and is about to paint them. Each egg should be painted one color out of 7: red, orange, yellow, green, blue, indigo or violet. Also, the following conditions should be satisfied: - Each of the seven colors should be used to paint at least one egg. - Any four eggs lying sequentially should be painted different colors. Help the Easter Rabbit paint the eggs in the required manner. We know that it is always possible.
The only line contains an integer *n* — the amount of eggs (7<=≤<=*n*<=≤<=100).
Print one line consisting of *n* characters. The *i*-th character should describe the color of the *i*-th egg in the order they lie in the circle. The colors should be represented as follows: "R" stands for red, "O" stands for orange, "Y" stands for yellow, "G" stands for green, "B" stands for blue, "I" stands for indigo, "V" stands for violet. If there are several answers, print any of them.
[ "8\n", "13\n" ]
[ "ROYGRBIV\n", "ROYGBIVGBIVYG\n" ]
The way the eggs will be painted in the first sample is shown on the picture:
[ { "input": "8", "output": "ROYGBIVG" }, { "input": "13", "output": "ROYGBIVOYGBIV" }, { "input": "7", "output": "ROYGBIV" }, { "input": "10", "output": "ROYGBIVYGB" }, { "input": "14", "output": "ROYGBIVROYGBIV" }, { "input": "50", "output": "ROYGB...
218
0
3.9455
822
760
Petr and a calendar
[ "implementation", "math" ]
null
null
Petr wants to make a calendar for current month. For this purpose he draws a table in which columns correspond to weeks (a week is seven consequent days from Monday to Sunday), rows correspond to weekdays, and cells contain dates. For example, a calendar for January 2017 should look like on the picture: Petr wants to know how many columns his table should have given the month and the weekday of the first date of that month? Assume that the year is non-leap.
The only line contain two integers *m* and *d* (1<=≤<=*m*<=≤<=12, 1<=≤<=*d*<=≤<=7) — the number of month (January is the first month, December is the twelfth) and the weekday of the first date of this month (1 is Monday, 7 is Sunday).
Print single integer: the number of columns the table should have.
[ "1 7\n", "1 1\n", "11 6\n" ]
[ "6\n", "5\n", "5\n" ]
The first example corresponds to the January 2017 shown on the picture in the statements. In the second example 1-st January is Monday, so the whole month fits into 5 columns. In the third example 1-st November is Saturday and 5 columns is enough.
[ { "input": "1 7", "output": "6" }, { "input": "1 1", "output": "5" }, { "input": "11 6", "output": "5" }, { "input": "2 7", "output": "5" }, { "input": "2 1", "output": "4" }, { "input": "8 6", "output": "6" }, { "input": "1 1", "output...
30
0
0
823
653
Bear and Compressing
[ "brute force", "dfs and similar", "dp", "strings" ]
null
null
Limak is a little polar bear. Polar bears hate long strings and thus they like to compress them. You should also know that Limak is so young that he knows only first six letters of the English alphabet: 'a', 'b', 'c', 'd', 'e' and 'f'. You are given a set of *q* possible operations. Limak can perform them in any order, any operation may be applied any number of times. The *i*-th operation is described by a string *a**i* of length two and a string *b**i* of length one. No two of *q* possible operations have the same string *a**i*. When Limak has a string *s* he can perform the *i*-th operation on *s* if the first two letters of *s* match a two-letter string *a**i*. Performing the *i*-th operation removes first two letters of *s* and inserts there a string *b**i*. See the notes section for further clarification. You may note that performing an operation decreases the length of a string *s* exactly by 1. Also, for some sets of operations there may be a string that cannot be compressed any further, because the first two letters don't match any *a**i*. Limak wants to start with a string of length *n* and perform *n*<=-<=1 operations to finally get a one-letter string "a". In how many ways can he choose the starting string to be able to get "a"? Remember that Limak can use only letters he knows.
The first line contains two integers *n* and *q* (2<=≤<=*n*<=≤<=6, 1<=≤<=*q*<=≤<=36) — the length of the initial string and the number of available operations. The next *q* lines describe the possible operations. The *i*-th of them contains two strings *a**i* and *b**i* (|*a**i*|<==<=2,<=|*b**i*|<==<=1). It's guaranteed that *a**i*<=≠<=*a**j* for *i*<=≠<=*j* and that all *a**i* and *b**i* consist of only first six lowercase English letters.
Print the number of strings of length *n* that Limak will be able to transform to string "a" by applying only operations given in the input.
[ "3 5\nab a\ncc c\nca a\nee c\nff d\n", "2 8\naf e\ndc d\ncc f\nbc b\nda b\neb a\nbb b\nff c\n", "6 2\nbb a\nba a\n" ]
[ "4\n", "1\n", "0\n" ]
In the first sample, we count initial strings of length 3 from which Limak can get a required string "a". There are 4 such strings: "abb", "cab", "cca", "eea". The first one Limak can compress using operation 1 two times (changing "ab" to a single "a"). The first operation would change "abb" to "ab" and the second operation would change "ab" to "a". Other three strings may be compressed as follows: - "cab" <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/70a0795f45d32287dba0eb83fc4a3f470c6e5537.png" style="max-width: 100.0%;max-height: 100.0%;"/> "ab" <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/70a0795f45d32287dba0eb83fc4a3f470c6e5537.png" style="max-width: 100.0%;max-height: 100.0%;"/> "a" - "cca" <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/70a0795f45d32287dba0eb83fc4a3f470c6e5537.png" style="max-width: 100.0%;max-height: 100.0%;"/> "ca" <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/70a0795f45d32287dba0eb83fc4a3f470c6e5537.png" style="max-width: 100.0%;max-height: 100.0%;"/> "a" - "eea" <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/70a0795f45d32287dba0eb83fc4a3f470c6e5537.png" style="max-width: 100.0%;max-height: 100.0%;"/> "ca" <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/70a0795f45d32287dba0eb83fc4a3f470c6e5537.png" style="max-width: 100.0%;max-height: 100.0%;"/> "a" In the second sample, the only correct initial string is "eb" because it can be immediately compressed to "a".
[ { "input": "3 5\nab a\ncc c\nca a\nee c\nff d", "output": "4" }, { "input": "2 8\naf e\ndc d\ncc f\nbc b\nda b\neb a\nbb b\nff c", "output": "1" }, { "input": "6 2\nbb a\nba a", "output": "0" }, { "input": "2 5\nfe b\nbb a\naf b\nfd b\nbf c", "output": "1" }, { "i...
280
5,120,000
3
824
545
Queue
[ "greedy", "implementation", "sortings" ]
null
null
Little girl Susie went shopping with her mom and she wondered how to improve service quality. There are *n* people in the queue. For each person we know time *t**i* needed to serve him. A person will be disappointed if the time he waits is more than the time needed to serve him. The time a person waits is the total time when all the people who stand in the queue in front of him are served. Susie thought that if we swap some people in the queue, then we can decrease the number of people who are disappointed. Help Susie find out what is the maximum number of not disappointed people can be achieved by swapping people in the queue.
The first line contains integer *n* (1<=≤<=*n*<=≤<=105). The next line contains *n* integers *t**i* (1<=≤<=*t**i*<=≤<=109), separated by spaces.
Print a single number — the maximum number of not disappointed people in the queue.
[ "5\n15 2 1 5 3\n" ]
[ "4\n" ]
Value 4 is achieved at such an arrangement, for example: 1, 2, 3, 5, 15. Thus, you can make everything feel not disappointed except for the person with time 5.
[ { "input": "5\n15 2 1 5 3", "output": "4" }, { "input": "15\n1 1 1 1 1 1 1 1 1 1 1 1 1 1 1", "output": "2" }, { "input": "10\n13 2 5 55 21 34 1 8 1 3", "output": "6" }, { "input": "10\n8 256 16 1 2 1 64 4 128 32", "output": "10" }, { "input": "10\n10000 40000 1000...
30
0
-1
828
937
Olympiad
[ "implementation", "sortings" ]
null
null
The recent All-Berland Olympiad in Informatics featured *n* participants with each scoring a certain amount of points. As the head of the programming committee, you are to determine the set of participants to be awarded with diplomas with respect to the following criteria: - At least one participant should get a diploma. - None of those with score equal to zero should get awarded. - When someone is awarded, all participants with score not less than his score should also be awarded. Determine the number of ways to choose a subset of participants that will receive the diplomas.
The first line contains a single integer *n* (1<=≤<=*n*<=≤<=100) — the number of participants. The next line contains a sequence of *n* integers *a*1,<=*a*2,<=...,<=*a**n* (0<=≤<=*a**i*<=≤<=600) — participants' scores. It's guaranteed that at least one participant has non-zero score.
Print a single integer — the desired number of ways.
[ "4\n1 3 3 2\n", "3\n1 1 1\n", "4\n42 0 0 42\n" ]
[ "3\n", "1\n", "1\n" ]
There are three ways to choose a subset in sample case one. 1. Only participants with 3 points will get diplomas. 1. Participants with 2 or 3 points will get diplomas. 1. Everyone will get a diploma! The only option in sample case two is to award everyone. Note that in sample case three participants with zero scores cannot get anything.
[ { "input": "4\n1 3 3 2", "output": "3" }, { "input": "3\n1 1 1", "output": "1" }, { "input": "4\n42 0 0 42", "output": "1" }, { "input": "10\n1 0 1 0 1 0 0 0 0 1", "output": "1" }, { "input": "10\n572 471 540 163 50 30 561 510 43 200", "output": "10" }, { ...
0
0
-1
829
225
Well-known Numbers
[ "binary search", "greedy", "number theory" ]
null
null
Numbers *k*-bonacci (*k* is integer, *k*<=&gt;<=1) are a generalization of Fibonacci numbers and are determined as follows: - *F*(*k*,<=*n*)<==<=0, for integer *n*, 1<=≤<=*n*<=&lt;<=*k*; - *F*(*k*,<=*k*)<==<=1; - *F*(*k*,<=*n*)<==<=*F*(*k*,<=*n*<=-<=1)<=+<=*F*(*k*,<=*n*<=-<=2)<=+<=...<=+<=*F*(*k*,<=*n*<=-<=*k*), for integer *n*, *n*<=&gt;<=*k*. Note that we determine the *k*-bonacci numbers, *F*(*k*,<=*n*), only for integer values of *n* and *k*. You've got a number *s*, represent it as a sum of several (at least two) distinct *k*-bonacci numbers.
The first line contains two integers *s* and *k* (1<=≤<=*s*,<=*k*<=≤<=109; *k*<=&gt;<=1).
In the first line print an integer *m* (*m*<=≥<=2) that shows how many numbers are in the found representation. In the second line print *m* distinct integers *a*1,<=*a*2,<=...,<=*a**m*. Each printed integer should be a *k*-bonacci number. The sum of printed integers must equal *s*. It is guaranteed that the answer exists. If there are several possible answers, print any of them.
[ "5 2\n", "21 5\n" ]
[ "3\n0 2 3\n", "3\n4 1 16\n" ]
none
[ { "input": "5 2", "output": "3\n0 2 3" }, { "input": "21 5", "output": "3\n4 1 16" }, { "input": "1 1000", "output": "2\n1 0 " }, { "input": "1000000000 1000000000", "output": "14\n536870912 268435456 134217728 33554432 16777216 8388608 1048576 524288 131072 32768 16384 2...
2,000
127,795,200
0
831
331
The Great Julya Calendar
[ "dp" ]
null
null
Yet another Armageddon is coming! This time the culprit is the Julya tribe calendar. The beavers in this tribe knew math very well. Smart Beaver, an archaeologist, got a sacred plate with a magic integer on it. The translation from Old Beaverish is as follows: "May the Great Beaver bless you! May your chacres open and may your third eye never turn blind from beholding the Truth! Take the magic number, subtract a digit from it (the digit must occur in the number) and get a new magic number. Repeat this operation until a magic number equals zero. The Earth will stand on Three Beavers for the time, equal to the number of subtractions you perform!" Distinct subtraction sequences can obviously get you different number of operations. But the Smart Beaver is ready to face the worst and is asking you to count the minimum number of operations he needs to reduce the magic number to zero.
The single line contains the magic integer *n*, 0<=≤<=*n*. - to get 20 points, you need to solve the problem with constraints: *n*<=≤<=106 (subproblem C1); - to get 40 points, you need to solve the problem with constraints: *n*<=≤<=1012 (subproblems C1+C2); - to get 100 points, you need to solve the problem with constraints: *n*<=≤<=1018 (subproblems C1+C2+C3).
Print a single integer — the minimum number of subtractions that turns the magic number to a zero.
[ "24\n" ]
[ "5" ]
In the first test sample the minimum number of operations can be reached by the following sequence of subtractions:
[ { "input": "24", "output": "5" }, { "input": "0", "output": "0" }, { "input": "3", "output": "1" }, { "input": "8", "output": "1" }, { "input": "9", "output": "1" }, { "input": "10", "output": "2" }, { "input": "31", "output": "6" }, ...
248
1,638,400
3
835
645
Amity Assessment
[ "brute force", "constructive algorithms", "implementation" ]
null
null
Bessie the cow and her best friend Elsie each received a sliding puzzle on Pi Day. Their puzzles consist of a 2<=×<=2 grid and three tiles labeled 'A', 'B', and 'C'. The three tiles sit on top of the grid, leaving one grid cell empty. To make a move, Bessie or Elsie can slide a tile adjacent to the empty cell into the empty cell as shown below: In order to determine if they are truly Best Friends For Life (BFFLs), Bessie and Elsie would like to know if there exists a sequence of moves that takes their puzzles to the same configuration (moves can be performed in both puzzles). Two puzzles are considered to be in the same configuration if each tile is on top of the same grid cell in both puzzles. Since the tiles are labeled with letters, rotations and reflections are not allowed.
The first two lines of the input consist of a 2<=×<=2 grid describing the initial configuration of Bessie's puzzle. The next two lines contain a 2<=×<=2 grid describing the initial configuration of Elsie's puzzle. The positions of the tiles are labeled 'A', 'B', and 'C', while the empty cell is labeled 'X'. It's guaranteed that both puzzles contain exactly one tile with each letter and exactly one empty position.
Output "YES"(without quotes) if the puzzles can reach the same configuration (and Bessie and Elsie are truly BFFLs). Otherwise, print "NO" (without quotes).
[ "AB\nXC\nXB\nAC\n", "AB\nXC\nAC\nBX\n" ]
[ "YES\n", "NO\n" ]
The solution to the first sample is described by the image. All Bessie needs to do is slide her 'A' tile down. In the second sample, the two puzzles can never be in the same configuration. Perhaps Bessie and Elsie are not meant to be friends after all...
[ { "input": "AB\nXC\nXB\nAC", "output": "YES" }, { "input": "AB\nXC\nAC\nBX", "output": "NO" }, { "input": "XC\nBA\nCB\nAX", "output": "NO" }, { "input": "AB\nXC\nAX\nCB", "output": "YES" }, { "input": "CB\nAX\nXA\nBC", "output": "YES" }, { "input": "BC...
77
307,200
3
838
660
Hard Process
[ "binary search", "dp", "two pointers" ]
null
null
You are given an array *a* with *n* elements. Each element of *a* is either 0 or 1. Let's denote the length of the longest subsegment of consecutive elements in *a*, consisting of only numbers one, as *f*(*a*). You can change no more than *k* zeroes to ones to maximize *f*(*a*).
The first line contains two integers *n* and *k* (1<=≤<=*n*<=≤<=3·105,<=0<=≤<=*k*<=≤<=*n*) — the number of elements in *a* and the parameter *k*. The second line contains *n* integers *a**i* (0<=≤<=*a**i*<=≤<=1) — the elements of *a*.
On the first line print a non-negative integer *z* — the maximal value of *f*(*a*) after no more than *k* changes of zeroes to ones. On the second line print *n* integers *a**j* — the elements of the array *a* after the changes. If there are multiple answers, you can print any one of them.
[ "7 1\n1 0 0 1 1 0 1\n", "10 2\n1 0 0 1 0 1 0 1 0 1\n" ]
[ "4\n1 0 0 1 1 1 1\n", "5\n1 0 0 1 1 1 1 1 0 1\n" ]
none
[ { "input": "7 1\n1 0 0 1 1 0 1", "output": "4\n1 0 0 1 1 1 1" }, { "input": "10 2\n1 0 0 1 0 1 0 1 0 1", "output": "5\n1 0 0 1 1 1 1 1 0 1" }, { "input": "1 0\n0", "output": "0\n0" }, { "input": "1 0\n0", "output": "0\n0" }, { "input": "7 0\n0 1 0 0 0 1 0", "o...
0
0
-1
839
712
Memory and Trident
[ "implementation", "strings" ]
null
null
Memory is performing a walk on the two-dimensional plane, starting at the origin. He is given a string *s* with his directions for motion: - An 'L' indicates he should move one unit left. - An 'R' indicates he should move one unit right. - A 'U' indicates he should move one unit up. - A 'D' indicates he should move one unit down. But now Memory wants to end at the origin. To do this, he has a special trident. This trident can replace any character in *s* with any of 'L', 'R', 'U', or 'D'. However, because he doesn't want to wear out the trident, he wants to make the minimum number of edits possible. Please tell Memory what is the minimum number of changes he needs to make to produce a string that, when walked, will end at the origin, or if there is no such string.
The first and only line contains the string *s* (1<=≤<=|*s*|<=≤<=100<=000) — the instructions Memory is given.
If there is a string satisfying the conditions, output a single integer — the minimum number of edits required. In case it's not possible to change the sequence in such a way that it will bring Memory to to the origin, output -1.
[ "RRU\n", "UDUR\n", "RUUR\n" ]
[ "-1\n", "1\n", "2\n" ]
In the first sample test, Memory is told to walk right, then right, then up. It is easy to see that it is impossible to edit these instructions to form a valid walk. In the second sample test, Memory is told to walk up, then down, then up, then right. One possible solution is to change *s* to "LDUR". This string uses 1 edit, which is the minimum possible. It also ends at the origin.
[ { "input": "RRU", "output": "-1" }, { "input": "UDUR", "output": "1" }, { "input": "RUUR", "output": "2" }, { "input": "DDDD", "output": "2" }, { "input": "RRRR", "output": "2" }, { "input": "RRRUUD", "output": "2" }, { "input": "UDURLRDURL...
108
307,200
3
840
808
Average Sleep Time
[ "data structures", "implementation", "math" ]
null
null
It's been almost a week since Polycarp couldn't get rid of insomnia. And as you may already know, one week in Berland lasts *k* days! When Polycarp went to a doctor with his problem, the doctor asked him about his sleeping schedule (more specifically, the average amount of hours of sleep per week). Luckily, Polycarp kept records of sleep times for the last *n* days. So now he has a sequence *a*1,<=*a*2,<=...,<=*a**n*, where *a**i* is the sleep time on the *i*-th day. The number of records is so large that Polycarp is unable to calculate the average value by himself. Thus he is asking you to help him with the calculations. To get the average Polycarp is going to consider *k* consecutive days as a week. So there will be *n*<=-<=*k*<=+<=1 weeks to take into consideration. For example, if *k*<==<=2, *n*<==<=3 and *a*<==<=[3,<=4,<=7], then the result is . You should write a program which will calculate average sleep times of Polycarp over all weeks.
The first line contains two integer numbers *n* and *k* (1<=≤<=*k*<=≤<=*n*<=≤<=2·105). The second line contains *n* integer numbers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=105).
Output average sleeping time over all weeks. The answer is considered to be correct if its absolute or relative error does not exceed 10<=-<=6. In particular, it is enough to output real number with at least 6 digits after the decimal point.
[ "3 2\n3 4 7\n", "1 1\n10\n", "8 2\n1 2 4 100000 123 456 789 1\n" ]
[ "9.0000000000\n", "10.0000000000\n", "28964.2857142857\n" ]
In the third example there are *n* - *k* + 1 = 7 weeks, so the answer is sums of all weeks divided by 7.
[ { "input": "3 2\n3 4 7", "output": "9.0000000000" }, { "input": "1 1\n10", "output": "10.0000000000" }, { "input": "8 2\n1 2 4 100000 123 456 789 1", "output": "28964.2857142857" }, { "input": "1 1\n1", "output": "1.0000000000" }, { "input": "1 1\n100000", "ou...
1,000
409,600
0
841
332
Maximum Absurdity
[ "data structures", "dp", "implementation" ]
null
null
Reforms continue entering Berland. For example, during yesterday sitting the Berland Parliament approved as much as *n* laws (each law has been assigned a unique number from 1 to *n*). Today all these laws were put on the table of the President of Berland, G.W. Boosch, to be signed. This time mr. Boosch plans to sign 2*k* laws. He decided to choose exactly two non-intersecting segments of integers from 1 to *n* of length *k* and sign all laws, whose numbers fall into these segments. More formally, mr. Boosch is going to choose two integers *a*, *b* (1<=≤<=*a*<=≤<=*b*<=≤<=*n*<=-<=*k*<=+<=1,<=*b*<=-<=*a*<=≥<=*k*) and sign all laws with numbers lying in the segments [*a*; *a*<=+<=*k*<=-<=1] and [*b*; *b*<=+<=*k*<=-<=1] (borders are included). As mr. Boosch chooses the laws to sign, he of course considers the public opinion. Allberland Public Opinion Study Centre (APOSC) conducted opinion polls among the citizens, processed the results into a report and gave it to the president. The report contains the absurdity value for each law, in the public opinion. As mr. Boosch is a real patriot, he is keen on signing the laws with the maximum total absurdity. Help him.
The first line contains two integers *n* and *k* (2<=≤<=*n*<=≤<=2·105, 0<=&lt;<=2*k*<=≤<=*n*) — the number of laws accepted by the parliament and the length of one segment in the law list, correspondingly. The next line contains *n* integers *x*1,<=*x*2,<=...,<=*x**n* — the absurdity of each law (1<=≤<=*x**i*<=≤<=109).
Print two integers *a*, *b* — the beginning of segments that mr. Boosch should choose. That means that the president signs laws with numbers from segments [*a*; *a*<=+<=*k*<=-<=1] and [*b*; *b*<=+<=*k*<=-<=1]. If there are multiple solutions, print the one with the minimum number *a*. If there still are multiple solutions, print the one with the minimum *b*.
[ "5 2\n3 6 1 1 6\n", "6 2\n1 1 1 1 1 1\n" ]
[ "1 4\n", "1 3\n" ]
In the first sample mr. Boosch signs laws with numbers from segments [1;2] and [4;5]. The total absurdity of the signed laws equals 3 + 6 + 1 + 6 = 16. In the second sample mr. Boosch signs laws with numbers from segments [1;2] and [3;4]. The total absurdity of the signed laws equals 1 + 1 + 1 + 1 = 4.
[ { "input": "5 2\n3 6 1 1 6", "output": "1 4" }, { "input": "6 2\n1 1 1 1 1 1", "output": "1 3" }, { "input": "6 2\n1 4 1 2 5 6", "output": "1 5" }, { "input": "4 1\n1 2 2 2", "output": "2 3" }, { "input": "6 3\n15 20 1 15 43 6", "output": "1 4" }, { "i...
278
27,648,000
3
843
698
Vacations
[ "dp" ]
null
null
Vasya has *n* days of vacations! So he decided to improve his IT skills and do sport. Vasya knows the following information about each of this *n* days: whether that gym opened and whether a contest was carried out in the Internet on that day. For the *i*-th day there are four options: 1. on this day the gym is closed and the contest is not carried out; 1. on this day the gym is closed and the contest is carried out; 1. on this day the gym is open and the contest is not carried out; 1. on this day the gym is open and the contest is carried out. On each of days Vasya can either have a rest or write the contest (if it is carried out on this day), or do sport (if the gym is open on this day). Find the minimum number of days on which Vasya will have a rest (it means, he will not do sport and write the contest at the same time). The only limitation that Vasya has — he does not want to do the same activity on two consecutive days: it means, he will not do sport on two consecutive days, and write the contest on two consecutive days.
The first line contains a positive integer *n* (1<=≤<=*n*<=≤<=100) — the number of days of Vasya's vacations. The second line contains the sequence of integers *a*1,<=*a*2,<=...,<=*a**n* (0<=≤<=*a**i*<=≤<=3) separated by space, where: - *a**i* equals 0, if on the *i*-th day of vacations the gym is closed and the contest is not carried out; - *a**i* equals 1, if on the *i*-th day of vacations the gym is closed, but the contest is carried out; - *a**i* equals 2, if on the *i*-th day of vacations the gym is open and the contest is not carried out; - *a**i* equals 3, if on the *i*-th day of vacations the gym is open and the contest is carried out.
Print the minimum possible number of days on which Vasya will have a rest. Remember that Vasya refuses: - to do sport on any two consecutive days, - to write the contest on any two consecutive days.
[ "4\n1 3 2 0\n", "7\n1 3 3 2 1 2 3\n", "2\n2 2\n" ]
[ "2\n", "0\n", "1\n" ]
In the first test Vasya can write the contest on the day number 1 and do sport on the day number 3. Thus, he will have a rest for only 2 days. In the second test Vasya should write contests on days number 1, 3, 5 and 7, in other days do sport. Thus, he will not have a rest for a single day. In the third test Vasya can do sport either on a day number 1 or number 2. He can not do sport in two days, because it will be contrary to the his limitation. Thus, he will have a rest for only one day.
[ { "input": "4\n1 3 2 0", "output": "2" }, { "input": "7\n1 3 3 2 1 2 3", "output": "0" }, { "input": "2\n2 2", "output": "1" }, { "input": "1\n0", "output": "1" }, { "input": "10\n0 0 1 1 0 0 0 0 1 0", "output": "8" }, { "input": "100\n3 2 3 3 3 2 3 1 ...
61
0
0
846
798
Mike and strings
[ "brute force", "dp", "strings" ]
null
null
Mike has *n* strings *s*1,<=*s*2,<=...,<=*s**n* each consisting of lowercase English letters. In one move he can choose a string *s**i*, erase the first character and append it to the end of the string. For example, if he has the string "coolmike", in one move he can transform it into the string "oolmikec". Now Mike asks himself: what is minimal number of moves that he needs to do in order to make all the strings equal?
The first line contains integer *n* (1<=≤<=*n*<=≤<=50) — the number of strings. This is followed by *n* lines which contain a string each. The *i*-th line corresponding to string *s**i*. Lengths of strings are equal. Lengths of each string is positive and don't exceed 50.
Print the minimal number of moves Mike needs in order to make all the strings equal or print <=-<=1 if there is no solution.
[ "4\nxzzwo\nzwoxz\nzzwox\nxzzwo\n", "2\nmolzv\nlzvmo\n", "3\nkc\nkc\nkc\n", "3\naa\naa\nab\n" ]
[ "5\n", "2\n", "0\n", "-1\n" ]
In the first sample testcase the optimal scenario is to perform operations in such a way as to transform all strings into "zwoxz".
[ { "input": "4\nxzzwo\nzwoxz\nzzwox\nxzzwo", "output": "5" }, { "input": "2\nmolzv\nlzvmo", "output": "2" }, { "input": "3\nkc\nkc\nkc", "output": "0" }, { "input": "3\naa\naa\nab", "output": "-1" }, { "input": "3\nkwkb\nkbkw\nbkwk", "output": "3" }, { ...
2,000
9,728,000
0
848
0
none
[ "none" ]
null
null
Iahub is very proud of his recent discovery, propagating trees. Right now, he invented a new tree, called xor-tree. After this new revolutionary discovery, he invented a game for kids which uses xor-trees. The game is played on a tree having *n* nodes, numbered from 1 to *n*. Each node *i* has an initial value *init**i*, which is either 0 or 1. The root of the tree is node 1. One can perform several (possibly, zero) operations on the tree during the game. The only available type of operation is to pick a node *x*. Right after someone has picked node *x*, the value of node *x* flips, the values of sons of *x* remain the same, the values of sons of sons of *x* flips, the values of sons of sons of sons of *x* remain the same and so on. The goal of the game is to get each node *i* to have value *goal**i*, which can also be only 0 or 1. You need to reach the goal of the game by using minimum number of operations.
The first line contains an integer *n* (1<=≤<=*n*<=≤<=105). Each of the next *n*<=-<=1 lines contains two integers *u**i* and *v**i* (1<=≤<=*u**i*,<=*v**i*<=≤<=*n*; *u**i*<=≠<=*v**i*) meaning there is an edge between nodes *u**i* and *v**i*. The next line contains *n* integer numbers, the *i*-th of them corresponds to *init**i* (*init**i* is either 0 or 1). The following line also contains *n* integer numbers, the *i*-th number corresponds to *goal**i* (*goal**i* is either 0 or 1).
In the first line output an integer number *cnt*, representing the minimal number of operations you perform. Each of the next *cnt* lines should contain an integer *x**i*, representing that you pick a node *x**i*.
[ "10\n2 1\n3 1\n4 2\n5 1\n6 2\n7 5\n8 6\n9 8\n10 5\n1 0 1 1 0 1 0 1 0 1\n1 0 1 0 0 1 1 1 0 1\n" ]
[ "2\n4\n7\n" ]
none
[ { "input": "10\n2 1\n3 1\n4 2\n5 1\n6 2\n7 5\n8 6\n9 8\n10 5\n1 0 1 1 0 1 0 1 0 1\n1 0 1 0 0 1 1 1 0 1", "output": "2\n4\n7" }, { "input": "15\n2 1\n3 2\n4 3\n5 4\n6 5\n7 6\n8 7\n9 8\n10 9\n11 10\n12 11\n13 12\n14 13\n15 14\n0 1 0 0 1 1 1 1 1 1 0 0 0 1 1\n1 1 1 1 0 0 1 1 0 1 0 0 1 1 0", "output"...
46
0
0
849
17
Noldbach problem
[ "brute force", "math", "number theory" ]
A. Noldbach problem
2
64
Nick is interested in prime numbers. Once he read about Goldbach problem. It states that every even integer greater than 2 can be expressed as the sum of two primes. That got Nick's attention and he decided to invent a problem of his own and call it Noldbach problem. Since Nick is interested only in prime numbers, Noldbach problem states that at least *k* prime numbers from 2 to *n* inclusively can be expressed as the sum of three integer numbers: two neighboring prime numbers and 1. For example, 19 = 7 + 11 + 1, or 13 = 5 + 7 + 1. Two prime numbers are called neighboring if there are no other prime numbers between them. You are to help Nick, and find out if he is right or wrong.
The first line of the input contains two integers *n* (2<=≤<=*n*<=≤<=1000) and *k* (0<=≤<=*k*<=≤<=1000).
Output YES if at least *k* prime numbers from 2 to *n* inclusively can be expressed as it was described above. Otherwise output NO.
[ "27 2\n", "45 7\n" ]
[ "YES", "NO" ]
In the first sample the answer is YES since at least two numbers can be expressed as it was described (for example, 13 and 19). In the second sample the answer is NO since it is impossible to express 7 prime numbers from 2 to 45 in the desired form.
[ { "input": "27 2", "output": "YES" }, { "input": "45 7", "output": "NO" }, { "input": "2 0", "output": "YES" }, { "input": "15 1", "output": "YES" }, { "input": "17 1", "output": "YES" }, { "input": "34 5", "output": "NO" }, { "input": "37 ...
186
0
0
855
976
Well played!
[ "greedy", "sortings" ]
null
null
Recently Max has got himself into popular CCG "BrainStone". As "BrainStone" is a pretty intellectual game, Max has to solve numerous hard problems during the gameplay. Here is one of them: Max owns *n* creatures, *i*-th of them can be described with two numbers — its health *hp**i* and its damage *dmg**i*. Max also has two types of spells in stock: 1. Doubles health of the creature (*hp**i* := *hp**i*·2); 1. Assigns value of health of the creature to its damage (*dmg**i* := *hp**i*). Spell of first type can be used no more than *a* times in total, of the second type — no more than *b* times in total. Spell can be used on a certain creature multiple times. Spells can be used in arbitrary order. It isn't necessary to use all the spells. Max is really busy preparing for his final exams, so he asks you to determine what is the maximal total damage of all creatures he can achieve if he uses spells in most optimal way.
The first line contains three integers *n*, *a*, *b* (1<=≤<=*n*<=≤<=2·105, 0<=≤<=*a*<=≤<=20, 0<=≤<=*b*<=≤<=2·105) — the number of creatures, spells of the first type and spells of the second type, respectively. The *i*-th of the next *n* lines contain two number *hp**i* and *dmg**i* (1<=≤<=*hp**i*,<=*dmg**i*<=≤<=109) — description of the *i*-th creature.
Print single integer — maximum total damage creatures can deal.
[ "2 1 1\n10 15\n6 1\n", "3 0 3\n10 8\n7 11\n5 2\n" ]
[ "27\n", "26\n" ]
In the first example Max should use the spell of the first type on the second creature, then the spell of the second type on the same creature. Then total damage will be equal to 15 + 6·2 = 27. In the second example Max should use the spell of the second type on the first creature, then the spell of the second type on the third creature. Total damage will be equal to 10 + 11 + 5 = 26.
[ { "input": "2 1 1\n10 15\n6 1", "output": "27" }, { "input": "3 0 3\n10 8\n7 11\n5 2", "output": "26" }, { "input": "1 0 0\n2 1", "output": "1" }, { "input": "1 0 200000\n1 2", "output": "2" }, { "input": "7 5 7\n29 25\n84 28\n34 34\n14 76\n85 9\n40 57\n99 88", ...
92
7,065,600
0
857
126
Password
[ "binary search", "dp", "hashing", "string suffix structures", "strings" ]
null
null
Asterix, Obelix and their temporary buddies Suffix and Prefix has finally found the Harmony temple. However, its doors were firmly locked and even Obelix had no luck opening them. A little later they found a string *s*, carved on a rock below the temple's gates. Asterix supposed that that's the password that opens the temple and read the string aloud. However, nothing happened. Then Asterix supposed that a password is some substring *t* of the string *s*. Prefix supposed that the substring *t* is the beginning of the string *s*; Suffix supposed that the substring *t* should be the end of the string *s*; and Obelix supposed that *t* should be located somewhere inside the string *s*, that is, *t* is neither its beginning, nor its end. Asterix chose the substring *t* so as to please all his companions. Besides, from all acceptable variants Asterix chose the longest one (as Asterix loves long strings). When Asterix read the substring *t* aloud, the temple doors opened. You know the string *s*. Find the substring *t* or determine that such substring does not exist and all that's been written above is just a nice legend.
You are given the string *s* whose length can vary from 1 to 106 (inclusive), consisting of small Latin letters.
Print the string *t*. If a suitable *t* string does not exist, then print "Just a legend" without the quotes.
[ "fixprefixsuffix\n", "abcdabc\n" ]
[ "fix", "Just a legend" ]
none
[ { "input": "fixprefixsuffix", "output": "fix" }, { "input": "abcdabc", "output": "Just a legend" }, { "input": "qwertyqwertyqwerty", "output": "qwerty" }, { "input": "papapapap", "output": "papap" }, { "input": "aaaaaaaaaa", "output": "aaaaaaaa" }, { "...
496
30,515,200
3
859
386
Second-Price Auction
[ "implementation" ]
null
null
In this problem we consider a special type of an auction, which is called the second-price auction. As in regular auction *n* bidders place a bid which is price a bidder ready to pay. The auction is closed, that is, each bidder secretly informs the organizer of the auction price he is willing to pay. After that, the auction winner is the participant who offered the highest price. However, he pay not the price he offers, but the highest price among the offers of other participants (hence the name: the second-price auction). Write a program that reads prices offered by bidders and finds the winner and the price he will pay. Consider that all of the offered prices are different.
The first line of the input contains *n* (2<=≤<=*n*<=≤<=1000) — number of bidders. The second line contains *n* distinct integer numbers *p*1,<=*p*2,<=... *p**n*, separated by single spaces (1<=≤<=*p**i*<=≤<=10000), where *p**i* stands for the price offered by the *i*-th bidder.
The single output line should contain two integers: index of the winner and the price he will pay. Indices are 1-based.
[ "2\n5 7\n", "3\n10 2 8\n", "6\n3 8 2 9 4 14\n" ]
[ "2 5\n", "1 8\n", "6 9\n" ]
none
[ { "input": "2\n5 7", "output": "2 5" }, { "input": "3\n10 2 8", "output": "1 8" }, { "input": "6\n3 8 2 9 4 14", "output": "6 9" }, { "input": "4\n4707 7586 4221 5842", "output": "2 5842" }, { "input": "5\n3304 4227 4869 6937 6002", "output": "4 6002" }, {...
109
307,200
3
865
630
Again Twenty Five!
[ "number theory" ]
null
null
The HR manager was disappointed again. The last applicant failed the interview the same way as 24 previous ones. "Do I give such a hard task?" — the HR manager thought. "Just raise number 5 to the power of *n* and get last two digits of the number. Yes, of course, *n* can be rather big, and one cannot find the power using a calculator, but we need people who are able to think, not just follow the instructions." Could you pass the interview in the machine vision company in IT City?
The only line of the input contains a single integer *n* (2<=≤<=*n*<=≤<=2·1018) — the power in which you need to raise number 5.
Output the last two digits of 5*n* without spaces between them.
[ "2\n" ]
[ "25" ]
none
[ { "input": "2", "output": "25" }, { "input": "7", "output": "25" }, { "input": "1000000000000000000", "output": "25" }, { "input": "2000000000000000000", "output": "25" }, { "input": "987654321012345678", "output": "25" } ]
500
1,331,200
0
867
895
Pizza Separation
[ "brute force", "implementation" ]
null
null
Students Vasya and Petya are studying at the BSU (Byteland State University). At one of the breaks they decided to order a pizza. In this problem pizza is a circle of some radius. The pizza was delivered already cut into *n* pieces. The *i*-th piece is a sector of angle equal to *a**i*. Vasya and Petya want to divide all pieces of pizza into two continuous sectors in such way that the difference between angles of these sectors is minimal. Sector angle is sum of angles of all pieces in it. Pay attention, that one of sectors can be empty.
The first line contains one integer *n* (1<=≤<=*n*<=≤<=360)  — the number of pieces into which the delivered pizza was cut. The second line contains *n* integers *a**i* (1<=≤<=*a**i*<=≤<=360)  — the angles of the sectors into which the pizza was cut. The sum of all *a**i* is 360.
Print one integer  — the minimal difference between angles of sectors that will go to Vasya and Petya.
[ "4\n90 90 90 90\n", "3\n100 100 160\n", "1\n360\n", "4\n170 30 150 10\n" ]
[ "0\n", "40\n", "360\n", "0\n" ]
In first sample Vasya can take 1 and 2 pieces, Petya can take 3 and 4 pieces. Then the answer is |(90 + 90) - (90 + 90)| = 0. In third sample there is only one piece of pizza that can be taken by only one from Vasya and Petya. So the answer is |360 - 0| = 360. In fourth sample Vasya can take 1 and 4 pieces, then Petya will take 2 and 3 pieces. So the answer is |(170 + 10) - (30 + 150)| = 0. Picture explaning fourth sample: <img class="tex-graphics" src="https://espresso.codeforces.com/4bb3450aca241f92fedcba5479bf1b6d22cf813d.png" style="max-width: 100.0%;max-height: 100.0%;"/> Both red and green sectors consist of two adjacent pieces of pizza. So Vasya can take green sector, then Petya will take red sector.
[ { "input": "4\n90 90 90 90", "output": "0" }, { "input": "3\n100 100 160", "output": "40" }, { "input": "1\n360", "output": "360" }, { "input": "4\n170 30 150 10", "output": "0" }, { "input": "5\n10 10 10 10 320", "output": "280" }, { "input": "8\n45 4...
77
1,536,000
0
869
432
Choosing Teams
[ "greedy", "implementation", "sortings" ]
null
null
The Saratov State University Olympiad Programmers Training Center (SSU OPTC) has *n* students. For each student you know the number of times he/she has participated in the ACM ICPC world programming championship. According to the ACM ICPC rules, each person can participate in the world championship at most 5 times. The head of the SSU OPTC is recently gathering teams to participate in the world championship. Each team must consist of exactly three people, at that, any person cannot be a member of two or more teams. What maximum number of teams can the head make if he wants each team to participate in the world championship with the same members at least *k* times?
The first line contains two integers, *n* and *k* (1<=≤<=*n*<=≤<=2000; 1<=≤<=*k*<=≤<=5). The next line contains *n* integers: *y*1,<=*y*2,<=...,<=*y**n* (0<=≤<=*y**i*<=≤<=5), where *y**i* shows the number of times the *i*-th person participated in the ACM ICPC world championship.
Print a single number — the answer to the problem.
[ "5 2\n0 4 5 1 0\n", "6 4\n0 1 2 3 4 5\n", "6 5\n0 0 0 0 0 0\n" ]
[ "1\n", "0\n", "2\n" ]
In the first sample only one team could be made: the first, the fourth and the fifth participants. In the second sample no teams could be created. In the third sample two teams could be created. Any partition into two teams fits.
[ { "input": "5 2\n0 4 5 1 0", "output": "1" }, { "input": "6 4\n0 1 2 3 4 5", "output": "0" }, { "input": "6 5\n0 0 0 0 0 0", "output": "2" }, { "input": "3 4\n0 1 0", "output": "1" }, { "input": "3 4\n0 2 0", "output": "0" }, { "input": "6 5\n0 0 0 0 0...
46
0
3
870
21
Jabber ID
[ "implementation", "strings" ]
A. Jabber ID
0
256
Jabber ID on the national Berland service «Babber» has a form &lt;username&gt;@&lt;hostname&gt;[/resource], where - &lt;username&gt; — is a sequence of Latin letters (lowercase or uppercase), digits or underscores characters «_», the length of &lt;username&gt; is between 1 and 16, inclusive. - &lt;hostname&gt; — is a sequence of word separated by periods (characters «.»), where each word should contain only characters allowed for &lt;username&gt;, the length of each word is between 1 and 16, inclusive. The length of &lt;hostname&gt; is between 1 and 32, inclusive. - &lt;resource&gt; — is a sequence of Latin letters (lowercase or uppercase), digits or underscores characters «_», the length of &lt;resource&gt; is between 1 and 16, inclusive. The content of square brackets is optional — it can be present or can be absent. There are the samples of correct Jabber IDs: [[email protected]](/cdn-cgi/l/email-protection), [[email protected]](/cdn-cgi/l/email-protection)/contest. Your task is to write program which checks if given string is a correct Jabber ID.
The input contains of a single line. The line has the length between 1 and 100 characters, inclusive. Each characters has ASCII-code between 33 and 127, inclusive.
Print YES or NO.
[ "[email protected]\n", "[email protected]/contest.icpc/12\n" ]
[ "YES\n", "NO\n" ]
none
[ { "input": "mike@codeforces.com", "output": "YES" }, { "input": "john.smith@codeforces.ru/contest.icpc/12", "output": "NO" }, { "input": "test@test.ri/abacaba", "output": "YES" }, { "input": "@ops", "output": "NO" }, { "input": "this-is-the-test", "output": "N...
46
0
-1
871
270
Fancy Fence
[ "geometry", "implementation", "math" ]
null
null
Emuskald needs a fence around his farm, but he is too lazy to build it himself. So he purchased a fence-building robot. He wants the fence to be a regular polygon. The robot builds the fence along a single path, but it can only make fence corners at a single angle *a*. Will the robot be able to build the fence Emuskald wants? In other words, is there a regular polygon which angles are equal to *a*?
The first line of input contains an integer *t* (0<=&lt;<=*t*<=&lt;<=180) — the number of tests. Each of the following *t* lines contains a single integer *a* (0<=&lt;<=*a*<=&lt;<=180) — the angle the robot can make corners at measured in degrees.
For each test, output on a single line "YES" (without quotes), if the robot can build a fence Emuskald wants, and "NO" (without quotes), if it is impossible.
[ "3\n30\n60\n90\n" ]
[ "NO\nYES\nYES\n" ]
In the first test case, it is impossible to build the fence, since there is no regular polygon with angle <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/df5f4b07dd5316fde165b43657b2696e2919e791.png" style="max-width: 100.0%;max-height: 100.0%;"/>. In the second test case, the fence is a regular triangle, and in the last test case — a square.
[ { "input": "3\n30\n60\n90", "output": "NO\nYES\nYES" }, { "input": "6\n1\n2\n3\n170\n179\n25", "output": "NO\nNO\nNO\nYES\nYES\nNO" } ]
62
0
0
877
919
Supermarket
[ "brute force", "greedy", "implementation" ]
null
null
We often go to supermarkets to buy some fruits or vegetables, and on the tag there prints the price for a kilo. But in some supermarkets, when asked how much the items are, the clerk will say that $a$ yuan for $b$ kilos (You don't need to care about what "yuan" is), the same as $a/b$ yuan for a kilo. Now imagine you'd like to buy $m$ kilos of apples. You've asked $n$ supermarkets and got the prices. Find the minimum cost for those apples. You can assume that there are enough apples in all supermarkets.
The first line contains two positive integers $n$ and $m$ ($1 \leq n \leq 5\,000$, $1 \leq m \leq 100$), denoting that there are $n$ supermarkets and you want to buy $m$ kilos of apples. The following $n$ lines describe the information of the supermarkets. Each line contains two positive integers $a, b$ ($1 \leq a, b \leq 100$), denoting that in this supermarket, you are supposed to pay $a$ yuan for $b$ kilos of apples.
The only line, denoting the minimum cost for $m$ kilos of apples. Please make sure that the absolute or relative error between your answer and the correct answer won't exceed $10^{-6}$. Formally, let your answer be $x$, and the jury's answer be $y$. Your answer is considered correct if $\frac{|x - y|}{\max{(1, |y|)}} \le 10^{-6}$.
[ "3 5\n1 2\n3 4\n1 3\n", "2 1\n99 100\n98 99\n" ]
[ "1.66666667\n", "0.98989899\n" ]
In the first sample, you are supposed to buy $5$ kilos of apples in supermarket $3$. The cost is $5/3$ yuan. In the second sample, you are supposed to buy $1$ kilo of apples in supermarket $2$. The cost is $98/99$ yuan.
[ { "input": "3 5\n1 2\n3 4\n1 3", "output": "1.66666667" }, { "input": "2 1\n99 100\n98 99", "output": "0.98989899" }, { "input": "50 37\n78 49\n96 4\n86 62\n28 4\n19 2\n79 43\n79 92\n95 35\n33 60\n54 84\n90 25\n2 25\n53 21\n86 52\n72 25\n6 78\n41 46\n3 68\n42 89\n33 35\n57 43\n99 45\n1 8...
62
102,400
3
880
29
Spit Problem
[ "brute force" ]
A. Spit Problem
2
256
In a Berland's zoo there is an enclosure with camels. It is known that camels like to spit. Bob watched these interesting animals for the whole day and registered in his notepad where each animal spitted. Now he wants to know if in the zoo there are two camels, which spitted at each other. Help him to solve this task. The trajectory of a camel's spit is an arc, i.e. if the camel in position *x* spits *d* meters right, he can hit only the camel in position *x*<=+<=*d*, if such a camel exists.
The first line contains integer *n* (1<=≤<=*n*<=≤<=100) — the amount of camels in the zoo. Each of the following *n* lines contains two integers *x**i* and *d**i* (<=-<=104<=≤<=*x**i*<=≤<=104,<=1<=≤<=|*d**i*|<=≤<=2·104) — records in Bob's notepad. *x**i* is a position of the *i*-th camel, and *d**i* is a distance at which the *i*-th camel spitted. Positive values of *d**i* correspond to the spits right, negative values correspond to the spits left. No two camels may stand in the same position.
If there are two camels, which spitted at each other, output YES. Otherwise, output NO.
[ "2\n0 1\n1 -1\n", "3\n0 1\n1 1\n2 -2\n", "5\n2 -10\n3 10\n0 5\n5 -5\n10 1\n" ]
[ "YES\n", "NO\n", "YES\n" ]
none
[ { "input": "2\n0 1\n1 -1", "output": "YES" }, { "input": "3\n0 1\n1 1\n2 -2", "output": "NO" }, { "input": "5\n2 -10\n3 10\n0 5\n5 -5\n10 1", "output": "YES" }, { "input": "10\n-9897 -1144\n-4230 -6350\n2116 -3551\n-3635 4993\n3907 -9071\n-2362 4120\n-6542 984\n5807 3745\n759...
92
0
3.977
881
519
A and B and Chess
[ "implementation" ]
null
null
A and B are preparing themselves for programming contests. To train their logical thinking and solve problems better, A and B decided to play chess. During the game A wondered whose position is now stronger. For each chess piece we know its weight: - the queen's weight is 9, - the rook's weight is 5, - the bishop's weight is 3, - the knight's weight is 3, - the pawn's weight is 1, - the king's weight isn't considered in evaluating position. The player's weight equals to the sum of weights of all his pieces on the board. As A doesn't like counting, he asked you to help him determine which player has the larger position weight.
The input contains eight lines, eight characters each — the board's description. The white pieces on the board are marked with uppercase letters, the black pieces are marked with lowercase letters. The white pieces are denoted as follows: the queen is represented is 'Q', the rook — as 'R', the bishop — as'B', the knight — as 'N', the pawn — as 'P', the king — as 'K'. The black pieces are denoted as 'q', 'r', 'b', 'n', 'p', 'k', respectively. An empty square of the board is marked as '.' (a dot). It is not guaranteed that the given chess position can be achieved in a real game. Specifically, there can be an arbitrary (possibly zero) number pieces of each type, the king may be under attack and so on.
Print "White" (without quotes) if the weight of the position of the white pieces is more than the weight of the position of the black pieces, print "Black" if the weight of the black pieces is more than the weight of the white pieces and print "Draw" if the weights of the white and black pieces are equal.
[ "...QK...\n........\n........\n........\n........\n........\n........\n...rk...\n", "rnbqkbnr\npppppppp\n........\n........\n........\n........\nPPPPPPPP\nRNBQKBNR\n", "rppppppr\n...k....\n........\n........\n........\n........\nK...Q...\n........\n" ]
[ "White\n", "Draw\n", "Black\n" ]
In the first test sample the weight of the position of the white pieces equals to 9, the weight of the position of the black pieces equals 5. In the second test sample the weights of the positions of the black and the white pieces are equal to 39. In the third test sample the weight of the position of the white pieces equals to 9, the weight of the position of the black pieces equals to 16.
[ { "input": "rnbqkbnr\npppppppp\n........\n........\n........\n........\nPPPPPPPP\nRNBQKBNR", "output": "Draw" }, { "input": "....bQ.K\n.B......\n.....P..\n........\n........\n........\n...N.P..\n.....R..", "output": "White" }, { "input": "b....p..\nR.......\n.pP...b.\npp......\nq.PPNpPR\...
77
0
3
882
439
Devu, the Singer and Churu, the Joker
[ "greedy", "implementation" ]
null
null
Devu is a renowned classical singer. He is invited to many big functions/festivals. Recently he was invited to "All World Classical Singing Festival". Other than Devu, comedian Churu was also invited. Devu has provided organizers a list of the songs and required time for singing them. He will sing *n* songs, *i**th* song will take *t**i* minutes exactly. The Comedian, Churu will crack jokes. All his jokes are of 5 minutes exactly. People have mainly come to listen Devu. But you know that he needs rest of 10 minutes after each song. On the other hand, Churu being a very active person, doesn't need any rest. You as one of the organizers should make an optimal sсhedule for the event. For some reasons you must follow the conditions: - The duration of the event must be no more than *d* minutes; - Devu must complete all his songs; - With satisfying the two previous conditions the number of jokes cracked by Churu should be as many as possible. If it is not possible to find a way to conduct all the songs of the Devu, output -1. Otherwise find out maximum number of jokes that Churu can crack in the grand event.
The first line contains two space separated integers *n*, *d* (1<=≤<=*n*<=≤<=100; 1<=≤<=*d*<=≤<=10000). The second line contains *n* space-separated integers: *t*1,<=*t*2,<=...,<=*t**n* (1<=≤<=*t**i*<=≤<=100).
If there is no way to conduct all the songs of Devu, output -1. Otherwise output the maximum number of jokes that Churu can crack in the grand event.
[ "3 30\n2 2 1\n", "3 20\n2 1 1\n" ]
[ "5\n", "-1\n" ]
Consider the first example. The duration of the event is 30 minutes. There could be maximum 5 jokes in the following way: - First Churu cracks a joke in 5 minutes. - Then Devu performs the first song for 2 minutes. - Then Churu cracks 2 jokes in 10 minutes. - Now Devu performs second song for 2 minutes. - Then Churu cracks 2 jokes in 10 minutes. - Now finally Devu will perform his last song in 1 minutes. Total time spent is 5 + 2 + 10 + 2 + 10 + 1 = 30 minutes. Consider the second example. There is no way of organizing Devu's all songs. Hence the answer is -1.
[ { "input": "3 30\n2 2 1", "output": "5" }, { "input": "3 20\n2 1 1", "output": "-1" }, { "input": "50 10000\n5 4 10 9 9 6 7 7 7 3 3 7 7 4 7 4 10 10 1 7 10 3 1 4 5 7 2 10 10 10 2 3 4 7 6 1 8 4 7 3 8 8 4 10 1 1 9 2 6 1", "output": "1943" }, { "input": "50 10000\n4 7 15 9 11 12 ...
93
0
3
887
99
Help Far Away Kingdom
[ "strings" ]
A. Help Far Away Kingdom
2
256
In a far away kingdom lived the King, the Prince, the Shoemaker, the Dressmaker and many other citizens. They lived happily until great trouble came into the Kingdom. The ACMers settled there. Most damage those strange creatures inflicted upon the kingdom was that they loved high precision numbers. As a result, the Kingdom healers had already had three appointments with the merchants who were asked to sell, say, exactly 0.273549107 beer barrels. To deal with the problem somehow, the King issued an order obliging rounding up all numbers to the closest integer to simplify calculations. Specifically, the order went like this: - If a number's integer part does not end with digit 9 and its fractional part is strictly less than 0.5, then the rounded up number coincides with the number’s integer part. - If a number's integer part does not end with digit 9 and its fractional part is not less than 0.5, the rounded up number is obtained if we add 1 to the last digit of the number’s integer part.- If the number’s integer part ends with digit 9, to round up the numbers one should go to Vasilisa the Wise. In the whole Kingdom she is the only one who can perform the tricky operation of carrying into the next position. Merchants found the algorithm very sophisticated and they asked you (the ACMers) to help them. Can you write a program that would perform the rounding according to the King’s order?
The first line contains a single number to round up — the integer part (a non-empty set of decimal digits that do not start with 0 — with the exception of a case when the set consists of a single digit — in this case 0 can go first), then follows character «.» (a dot), and then follows the fractional part (any non-empty set of decimal digits). The number's length does not exceed 1000 characters, including the dot. There are no other characters in the input data.
If the last number of the integer part is not equal to 9, print the rounded-up number without leading zeroes. Otherwise, print the message "GOTO Vasilisa." (without the quotes).
[ "0.0\n", "1.49\n", "1.50\n", "2.71828182845904523536\n", "3.14159265358979323846\n", "12345678901234567890.1\n", "123456789123456789.999\n" ]
[ "0", "1", "2", "3", "3", "12345678901234567890", "GOTO Vasilisa." ]
none
[ { "input": "0.0", "output": "0" }, { "input": "1.49", "output": "1" }, { "input": "1.50", "output": "2" }, { "input": "2.71828182845904523536", "output": "3" }, { "input": "3.14159265358979323846", "output": "3" }, { "input": "12345678901234567890.1", ...
92
0
0
890
910
The Way to Home
[ "dfs and similar", "dp", "greedy", "implementation" ]
null
null
A frog lives on the axis *Ox* and needs to reach home which is in the point *n*. She starts from the point 1. The frog can jump to the right at a distance not more than *d*. So, after she jumped from the point *x* she can reach the point *x*<=+<=*a*, where *a* is an integer from 1 to *d*. For each point from 1 to *n* is known if there is a lily flower in it. The frog can jump only in points with a lilies. Guaranteed that there are lilies in the points 1 and *n*. Determine the minimal number of jumps that the frog needs to reach home which is in the point *n* from the point 1. Consider that initially the frog is in the point 1. If the frog can not reach home, print -1.
The first line contains two integers *n* and *d* (2<=≤<=*n*<=≤<=100, 1<=≤<=*d*<=≤<=*n*<=-<=1) — the point, which the frog wants to reach, and the maximal length of the frog jump. The second line contains a string *s* of length *n*, consisting of zeros and ones. If a character of the string *s* equals to zero, then in the corresponding point there is no lily flower. In the other case, in the corresponding point there is a lily flower. Guaranteed that the first and the last characters of the string *s* equal to one.
If the frog can not reach the home, print -1. In the other case, print the minimal number of jumps that the frog needs to reach the home which is in the point *n* from the point 1.
[ "8 4\n10010101\n", "4 2\n1001\n", "8 4\n11100101\n", "12 3\n101111100101\n" ]
[ "2\n", "-1\n", "3\n", "4\n" ]
In the first example the from can reach home in two jumps: the first jump from the point 1 to the point 4 (the length of the jump is three), and the second jump from the point 4 to the point 8 (the length of the jump is four). In the second example the frog can not reach home, because to make it she need to jump on a distance three, but the maximum length of her jump equals to two.
[ { "input": "8 4\n10010101", "output": "2" }, { "input": "4 2\n1001", "output": "-1" }, { "input": "8 4\n11100101", "output": "3" }, { "input": "12 3\n101111100101", "output": "4" }, { "input": "5 4\n11011", "output": "1" }, { "input": "5 4\n10001", ...
62
614,400
3
892
38
Chess
[ "brute force", "implementation", "math" ]
B. Chess
2
256
Two chess pieces, a rook and a knight, stand on a standard chessboard 8<=×<=8 in size. The positions in which they are situated are known. It is guaranteed that none of them beats the other one. Your task is to find the number of ways to place another knight on the board so that none of the three pieces on the board beat another one. A new piece can only be placed on an empty square.
The first input line contains the description of the rook's position on the board. This description is a line which is 2 in length. Its first symbol is a lower-case Latin letter from a to h, and its second symbol is a number from 1 to 8. The second line contains the description of the knight's position in a similar way. It is guaranteed that their positions do not coincide.
Print a single number which is the required number of ways.
[ "a1\nb2\n", "a8\nd4\n" ]
[ "44\n", "38\n" ]
none
[ { "input": "a1\nb2", "output": "44" }, { "input": "a8\nd4", "output": "38" }, { "input": "a8\nf1", "output": "42" }, { "input": "f8\nh3", "output": "42" }, { "input": "g8\nb7", "output": "42" }, { "input": "h1\ng5", "output": "42" }, { "inp...
716
14,336,000
3.794297
893
137
Permutation
[ "greedy" ]
null
null
"Hey, it's homework time" — thought Polycarpus and of course he started with his favourite subject, IT. Polycarpus managed to solve all tasks but for the last one in 20 minutes. However, as he failed to solve the last task after some considerable time, the boy asked you to help him. The sequence of *n* integers is called a permutation if it contains all integers from 1 to *n* exactly once. You are given an arbitrary sequence *a*1,<=*a*2,<=...,<=*a**n* containing *n* integers. Each integer is not less than 1 and not greater than 5000. Determine what minimum number of elements Polycarpus needs to change to get a permutation (he should not delete or add numbers). In a single change he can modify any single sequence element (i. e. replace it with another integer).
The first line of the input data contains an integer *n* (1<=≤<=*n*<=≤<=5000) which represents how many numbers are in the sequence. The second line contains a sequence of integers *a**i* (1<=≤<=*a**i*<=≤<=5000,<=1<=≤<=*i*<=≤<=*n*).
Print the only number — the minimum number of changes needed to get the permutation.
[ "3\n3 1 2\n", "2\n2 2\n", "5\n5 3 3 3 1\n" ]
[ "0\n", "1\n", "2\n" ]
The first sample contains the permutation, which is why no replacements are required. In the second sample it is enough to replace the first element with the number 1 and that will make the sequence the needed permutation. In the third sample we can replace the second element with number 4 and the fourth element with number 2.
[ { "input": "3\n3 1 2", "output": "0" }, { "input": "2\n2 2", "output": "1" }, { "input": "5\n5 3 3 3 1", "output": "2" }, { "input": "5\n6 6 6 6 6", "output": "5" }, { "input": "10\n1 1 2 2 8 8 7 7 9 9", "output": "5" }, { "input": "8\n9 8 7 6 5 4 3 2"...
62
0
0
894
0
none
[ "none" ]
null
null
You are given *n* distinct points on a plane with integral coordinates. For each point you can either draw a vertical line through it, draw a horizontal line through it, or do nothing. You consider several coinciding straight lines as a single one. How many distinct pictures you can get? Print the answer modulo 109<=+<=7.
The first line contains single integer *n* (1<=≤<=*n*<=≤<=105) — the number of points. *n* lines follow. The (*i*<=+<=1)-th of these lines contains two integers *x**i*, *y**i* (<=-<=109<=≤<=*x**i*,<=*y**i*<=≤<=109) — coordinates of the *i*-th point. It is guaranteed that all points are distinct.
Print the number of possible distinct pictures modulo 109<=+<=7.
[ "4\n1 1\n1 2\n2 1\n2 2\n", "2\n-1 -1\n0 1\n" ]
[ "16\n", "9\n" ]
In the first example there are two vertical and two horizontal lines passing through the points. You can get pictures with any subset of these lines. For example, you can get the picture containing all four lines in two ways (each segment represents a line containing it). In the second example you can work with two points independently. The number of pictures is 3<sup class="upper-index">2</sup> = 9.
[]
78
512,000
0
895
624
Making a String
[ "greedy", "sortings" ]
null
null
You are given an alphabet consisting of *n* letters, your task is to make a string of the maximum possible length so that the following conditions are satisfied: - the *i*-th letter occurs in the string no more than *a**i* times; - the number of occurrences of each letter in the string must be distinct for all the letters that occurred in the string at least once.
The first line of the input contains a single integer *n* (2<=<=≤<=<=*n*<=<=≤<=<=26) — the number of letters in the alphabet. The next line contains *n* integers *a**i* (1<=≤<=*a**i*<=≤<=109) — *i*-th of these integers gives the limitation on the number of occurrences of the *i*-th character in the string.
Print a single integer — the maximum length of the string that meets all the requirements.
[ "3\n2 5 5\n", "3\n1 1 2\n" ]
[ "11\n", "3\n" ]
For convenience let's consider an alphabet consisting of three letters: "a", "b", "c". In the first sample, some of the optimal strings are: "cccaabbccbb", "aabcbcbcbcb". In the second sample some of the optimal strings are: "acc", "cbc".
[ { "input": "3\n2 5 5", "output": "11" }, { "input": "3\n1 1 2", "output": "3" }, { "input": "2\n1 1", "output": "1" }, { "input": "3\n1 1000000000 2", "output": "1000000003" }, { "input": "26\n1000000000 1000000000 1000000000 1000000000 1000000000 1000000000 10000...
1,000
0
0
896
0
none
[ "none" ]
null
null
Little Artem found a grasshopper. He brought it to his house and constructed a jumping area for him. The area looks like a strip of cells 1<=×<=*n*. Each cell contains the direction for the next jump and the length of that jump. Grasshopper starts in the first cell and follows the instructions written on the cells. Grasshopper stops immediately if it jumps out of the strip. Now Artem wants to find out if this will ever happen.
The first line of the input contains a single integer *n* (1<=≤<=*n*<=≤<=100<=000) — length of the strip. Next line contains a string of length *n* which consists of characters "&lt;" and "&gt;" only, that provide the direction of the jump from the corresponding cell. Next line contains *n* integers *d**i* (1<=≤<=*d**i*<=≤<=109) — the length of the jump from the *i*-th cell.
Print "INFINITE" (without quotes) if grasshopper will continue his jumps forever. Otherwise print "FINITE" (without quotes).
[ "2\n&gt;&lt;\n1 2\n", "3\n&gt;&gt;&lt;\n2 1 1\n" ]
[ "FINITE\n", "INFINITE" ]
In the first sample grasshopper starts from the first cell and jumps to the right on the next cell. When he is in the second cell he needs to jump two cells left so he will jump out of the strip. Second sample grasshopper path is 1 - 3 - 2 - 3 - 2 - 3 and so on. The path is infinite.
[ { "input": "2\n><\n1 2", "output": "FINITE" }, { "input": "3\n>><\n2 1 1", "output": "INFINITE" }, { "input": "1\n>\n1000000000", "output": "FINITE" }, { "input": "1\n<\n1000000000", "output": "FINITE" }, { "input": "2\n>>\n1 1", "output": "FINITE" }, { ...
2,000
93,696,000
0
897
510
Fox And Two Dots
[ "dfs and similar" ]
null
null
Fox Ciel is playing a mobile puzzle game called "Two Dots". The basic levels are played on a board of size *n*<=×<=*m* cells, like this: Each cell contains a dot that has some color. We will use different uppercase Latin characters to express different colors. The key of this game is to find a cycle that contain dots of same color. Consider 4 blue dots on the picture forming a circle as an example. Formally, we call a sequence of dots *d*1,<=*d*2,<=...,<=*d**k* a cycle if and only if it meets the following condition: 1. These *k* dots are different: if *i*<=≠<=*j* then *d**i* is different from *d**j*. 1. *k* is at least 4. 1. All dots belong to the same color. 1. For all 1<=≤<=*i*<=≤<=*k*<=-<=1: *d**i* and *d**i*<=+<=1 are adjacent. Also, *d**k* and *d*1 should also be adjacent. Cells *x* and *y* are called adjacent if they share an edge. Determine if there exists a cycle on the field.
The first line contains two integers *n* and *m* (2<=≤<=*n*,<=*m*<=≤<=50): the number of rows and columns of the board. Then *n* lines follow, each line contains a string consisting of *m* characters, expressing colors of dots in each line. Each character is an uppercase Latin letter.
Output "Yes" if there exists a cycle, and "No" otherwise.
[ "3 4\nAAAA\nABCA\nAAAA\n", "3 4\nAAAA\nABCA\nAADA\n", "4 4\nYYYR\nBYBY\nBBBY\nBBBY\n", "7 6\nAAAAAB\nABBBAB\nABAAAB\nABABBB\nABAAAB\nABBBAB\nAAAAAB\n", "2 13\nABCDEFGHIJKLM\nNOPQRSTUVWXYZ\n" ]
[ "Yes\n", "No\n", "Yes\n", "Yes\n", "No\n" ]
In first sample test all 'A' form a cycle. In second sample there is no such cycle. The third sample is displayed on the picture above ('Y' = Yellow, 'B' = Blue, 'R' = Red).
[ { "input": "3 4\nAAAA\nABCA\nAAAA", "output": "Yes" }, { "input": "3 4\nAAAA\nABCA\nAADA", "output": "No" }, { "input": "4 4\nYYYR\nBYBY\nBBBY\nBBBY", "output": "Yes" }, { "input": "7 6\nAAAAAB\nABBBAB\nABAAAB\nABABBB\nABAAAB\nABBBAB\nAAAAAB", "output": "Yes" }, { ...
46
1,331,200
-1
898
568
Primes or Palindromes?
[ "brute force", "implementation", "math", "number theory" ]
null
null
Rikhail Mubinchik believes that the current definition of prime numbers is obsolete as they are too complex and unpredictable. A palindromic number is another matter. It is aesthetically pleasing, and it has a number of remarkable properties. Help Rikhail to convince the scientific community in this! Let us remind you that a number is called prime if it is integer larger than one, and is not divisible by any positive integer other than itself and one. Rikhail calls a number a palindromic if it is integer, positive, and its decimal representation without leading zeros is a palindrome, i.e. reads the same from left to right and right to left. One problem with prime numbers is that there are too many of them. Let's introduce the following notation: π(*n*) — the number of primes no larger than *n*, *rub*(*n*) — the number of palindromic numbers no larger than *n*. Rikhail wants to prove that there are a lot more primes than palindromic ones. He asked you to solve the following problem: for a given value of the coefficient *A* find the maximum *n*, such that π(*n*)<=≤<=*A*·*rub*(*n*).
The input consists of two positive integers *p*, *q*, the numerator and denominator of the fraction that is the value of *A* (, ).
If such maximum number exists, then print it. Otherwise, print "Palindromic tree is better than splay tree" (without the quotes).
[ "1 1\n", "1 42\n", "6 4\n" ]
[ "40\n", "1\n", "172\n" ]
none
[ { "input": "1 1", "output": "40" }, { "input": "1 42", "output": "1" }, { "input": "6 4", "output": "172" }, { "input": "3 1", "output": "2530" }, { "input": "42 1", "output": "1179858" }, { "input": "10000 239", "output": "1168638" }, { "i...
62
0
0
900
998
Cutting
[ "dp", "greedy", "sortings" ]
null
null
There are a lot of things which could be cut — trees, paper, "the rope". In this problem you are going to cut a sequence of integers. There is a sequence of integers, which contains the equal number of even and odd numbers. Given a limited budget, you need to make maximum possible number of cuts such that each resulting segment will have the same number of odd and even integers. Cuts separate a sequence to continuous (contiguous) segments. You may think about each cut as a break between two adjacent elements in a sequence. So after cutting each element belongs to exactly one segment. Say, $[4, 1, 2, 3, 4, 5, 4, 4, 5, 5]$ $\to$ two cuts $\to$ $[4, 1 | 2, 3, 4, 5 | 4, 4, 5, 5]$. On each segment the number of even elements should be equal to the number of odd elements. The cost of the cut between $x$ and $y$ numbers is $|x - y|$ bitcoins. Find the maximum possible number of cuts that can be made while spending no more than $B$ bitcoins.
First line of the input contains an integer $n$ ($2 \le n \le 100$) and an integer $B$ ($1 \le B \le 100$) — the number of elements in the sequence and the number of bitcoins you have. Second line contains $n$ integers: $a_1$, $a_2$, ..., $a_n$ ($1 \le a_i \le 100$) — elements of the sequence, which contains the equal number of even and odd numbers
Print the maximum possible number of cuts which can be made while spending no more than $B$ bitcoins.
[ "6 4\n1 2 5 10 15 20\n", "4 10\n1 3 2 4\n", "6 100\n1 2 3 4 5 6\n" ]
[ "1\n", "0\n", "2\n" ]
In the first sample the optimal answer is to split sequence between $2$ and $5$. Price of this cut is equal to $3$ bitcoins. In the second sample it is not possible to make even one cut even with unlimited number of bitcoins. In the third sample the sequence should be cut between $2$ and $3$, and between $4$ and $5$. The total price of the cuts is $1 + 1 = 2$ bitcoins.
[ { "input": "6 4\n1 2 5 10 15 20", "output": "1" }, { "input": "4 10\n1 3 2 4", "output": "0" }, { "input": "6 100\n1 2 3 4 5 6", "output": "2" }, { "input": "2 100\n13 78", "output": "0" }, { "input": "10 1\n56 56 98 2 11 64 97 41 95 53", "output": "0" }, ...
78
0
3
904
873
Balanced Substring
[ "dp", "implementation" ]
null
null
You are given a string *s* consisting only of characters 0 and 1. A substring [*l*,<=*r*] of *s* is a string *s**l**s**l*<=+<=1*s**l*<=+<=2... *s**r*, and its length equals to *r*<=-<=*l*<=+<=1. A substring is called balanced if the number of zeroes (0) equals to the number of ones in this substring. You have to determine the length of the longest balanced substring of *s*.
The first line contains *n* (1<=≤<=*n*<=≤<=100000) — the number of characters in *s*. The second line contains a string *s* consisting of exactly *n* characters. Only characters 0 and 1 can appear in *s*.
If there is no non-empty balanced substring in *s*, print 0. Otherwise, print the length of the longest balanced substring.
[ "8\n11010111\n", "3\n111\n" ]
[ "4\n", "0\n" ]
In the first example you can choose the substring [3, 6]. It is balanced, and its length is 4. Choosing the substring [2, 5] is also possible. In the second example it's impossible to find a non-empty balanced substring.
[ { "input": "8\n11010111", "output": "4" }, { "input": "3\n111", "output": "0" }, { "input": "11\n00001000100", "output": "2" }, { "input": "10\n0100000000", "output": "2" }, { "input": "13\n0001000011010", "output": "6" }, { "input": "14\n0000010010101...
46
5,632,000
-1
906
217
Ice Skating
[ "brute force", "dfs and similar", "dsu", "graphs" ]
null
null
Bajtek is learning to skate on ice. He's a beginner, so his only mode of transportation is pushing off from a snow drift to the north, east, south or west and sliding until he lands in another snow drift. He has noticed that in this way it's impossible to get from some snow drifts to some other by any sequence of moves. He now wants to heap up some additional snow drifts, so that he can get from any snow drift to any other one. He asked you to find the minimal number of snow drifts that need to be created. We assume that Bajtek can only heap up snow drifts at integer coordinates.
The first line of input contains a single integer *n* (1<=≤<=*n*<=≤<=100) — the number of snow drifts. Each of the following *n* lines contains two integers *x**i* and *y**i* (1<=≤<=*x**i*,<=*y**i*<=≤<=1000) — the coordinates of the *i*-th snow drift. Note that the north direction coinсides with the direction of *Oy* axis, so the east direction coinсides with the direction of the *Ox* axis. All snow drift's locations are distinct.
Output the minimal number of snow drifts that need to be created in order for Bajtek to be able to reach any snow drift from any other one.
[ "2\n2 1\n1 2\n", "2\n2 1\n4 1\n" ]
[ "1\n", "0\n" ]
none
[ { "input": "2\n2 1\n1 2", "output": "1" }, { "input": "2\n2 1\n4 1", "output": "0" }, { "input": "24\n171 35\n261 20\n4 206\n501 446\n961 912\n581 748\n946 978\n463 514\n841 889\n341 466\n842 967\n54 102\n235 261\n925 889\n682 672\n623 636\n268 94\n635 710\n474 510\n697 794\n586 663\n182...
186
0
0
910
735
Ostap and Grasshopper
[ "implementation", "strings" ]
null
null
On the way to Rio de Janeiro Ostap kills time playing with a grasshopper he took with him in a special box. Ostap builds a line of length *n* such that some cells of this line are empty and some contain obstacles. Then, he places his grasshopper to one of the empty cells and a small insect in another empty cell. The grasshopper wants to eat the insect. Ostap knows that grasshopper is able to jump to any empty cell that is exactly *k* cells away from the current (to the left or to the right). Note that it doesn't matter whether intermediate cells are empty or not as the grasshopper makes a jump over them. For example, if *k*<==<=1 the grasshopper can jump to a neighboring cell only, and if *k*<==<=2 the grasshopper can jump over a single cell. Your goal is to determine whether there is a sequence of jumps such that grasshopper will get from his initial position to the cell with an insect.
The first line of the input contains two integers *n* and *k* (2<=≤<=*n*<=≤<=100, 1<=≤<=*k*<=≤<=*n*<=-<=1) — the number of cells in the line and the length of one grasshopper's jump. The second line contains a string of length *n* consisting of characters '.', '#', 'G' and 'T'. Character '.' means that the corresponding cell is empty, character '#' means that the corresponding cell contains an obstacle and grasshopper can't jump there. Character 'G' means that the grasshopper starts at this position and, finally, 'T' means that the target insect is located at this cell. It's guaranteed that characters 'G' and 'T' appear in this line exactly once.
If there exists a sequence of jumps (each jump of length *k*), such that the grasshopper can get from his initial position to the cell with the insect, print "YES" (without quotes) in the only line of the input. Otherwise, print "NO" (without quotes).
[ "5 2\n#G#T#\n", "6 1\nT....G\n", "7 3\nT..#..G\n", "6 2\n..GT..\n" ]
[ "YES\n", "YES\n", "NO\n", "NO\n" ]
In the first sample, the grasshopper can make one jump to the right in order to get from cell 2 to cell 4. In the second sample, the grasshopper is only able to jump to neighboring cells but the way to the insect is free — he can get there by jumping left 5 times. In the third sample, the grasshopper can't make a single jump. In the fourth sample, the grasshopper can only jump to the cells with odd indices, thus he won't be able to reach the insect.
[ { "input": "5 2\n#G#T#", "output": "YES" }, { "input": "6 1\nT....G", "output": "YES" }, { "input": "7 3\nT..#..G", "output": "NO" }, { "input": "6 2\n..GT..", "output": "NO" }, { "input": "2 1\nGT", "output": "YES" }, { "input": "100 5\nG####.####.###...
46
0
3
912
158
Next Round
[ "*special", "implementation" ]
null
null
"Contestant who earns a score equal to or greater than the *k*-th place finisher's score will advance to the next round, as long as the contestant earns a positive score..." — an excerpt from contest rules. A total of *n* participants took part in the contest (*n*<=≥<=*k*), and you already know their scores. Calculate how many participants will advance to the next round.
The first line of the input contains two integers *n* and *k* (1<=≤<=*k*<=≤<=*n*<=≤<=50) separated by a single space. The second line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (0<=≤<=*a**i*<=≤<=100), where *a**i* is the score earned by the participant who got the *i*-th place. The given sequence is non-increasing (that is, for all *i* from 1 to *n*<=-<=1 the following condition is fulfilled: *a**i*<=≥<=*a**i*<=+<=1).
Output the number of participants who advance to the next round.
[ "8 5\n10 9 8 7 7 7 5 5\n", "4 2\n0 0 0 0\n" ]
[ "6\n", "0\n" ]
In the first example the participant on the 5th place earned 7 points. As the participant on the 6th place also earned 7 points, there are 6 advancers. In the second example nobody got a positive score.
[ { "input": "8 5\n10 9 8 7 7 7 5 5", "output": "6" }, { "input": "4 2\n0 0 0 0", "output": "0" }, { "input": "5 1\n1 1 1 1 1", "output": "5" }, { "input": "5 5\n1 1 1 1 1", "output": "5" }, { "input": "1 1\n10", "output": "1" }, { "input": "17 14\n16 15...
60
0
0
913
705
Hulk
[ "implementation" ]
null
null
Dr. Bruce Banner hates his enemies (like others don't). As we all know, he can barely talk when he turns into the incredible Hulk. That's why he asked you to help him to express his feelings. Hulk likes the Inception so much, and like that his feelings are complicated. They have *n* layers. The first layer is hate, second one is love, third one is hate and so on... For example if *n*<==<=1, then his feeling is "I hate it" or if *n*<==<=2 it's "I hate that I love it", and if *n*<==<=3 it's "I hate that I love that I hate it" and so on. Please help Dr. Banner.
The only line of the input contains a single integer *n* (1<=≤<=*n*<=≤<=100) — the number of layers of love and hate.
Print Dr.Banner's feeling in one line.
[ "1\n", "2\n", "3\n" ]
[ "I hate it\n", "I hate that I love it\n", "I hate that I love that I hate it\n" ]
none
[ { "input": "1", "output": "I hate it" }, { "input": "2", "output": "I hate that I love it" }, { "input": "3", "output": "I hate that I love that I hate it" }, { "input": "4", "output": "I hate that I love that I hate that I love it" }, { "input": "5", "output"...
46
0
3
916