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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*|<=≀<=3Β·105). The string *s* contains only digits from 0 to 9.
Print integer *a* β€” 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
614,400
3
939
300
Beautiful Numbers
[ "brute force", "combinatorics" ]
null
null
Vitaly is a very weird man. He's got two favorite digits *a* and *b*. Vitaly calls a positive integer good, if the decimal representation of this integer only contains digits *a* and *b*. Vitaly calls a good number excellent, if the sum of its digits is a good number. For example, let's say that Vitaly's favourite digits are 1 and 3, then number 12 isn't good and numbers 13 or 311 are. Also, number 111 is excellent and number 11 isn't. Now Vitaly is wondering, how many excellent numbers of length exactly *n* are there. As this number can be rather large, he asks you to count the remainder after dividing it by 1000000007 (109<=+<=7). A number's length is the number of digits in its decimal representation without leading zeroes.
The first line contains three integers: *a*, *b*, *n* (1<=≀<=*a*<=&lt;<=*b*<=≀<=9,<=1<=≀<=*n*<=≀<=106).
Print a single integer β€” the answer to the problem modulo 1000000007 (109<=+<=7).
[ "1 3 3\n", "2 3 10\n" ]
[ "1\n", "165\n" ]
none
[ { "input": "1 3 3", "output": "1" }, { "input": "2 3 10", "output": "165" }, { "input": "6 8 14215", "output": "651581472" }, { "input": "4 9 104671", "output": "329390901" }, { "input": "6 7 78755", "output": "0" }, { "input": "1 8 265", "output":...
1,090
27,648,000
3
940
633
Ebony and Ivory
[ "brute force", "math", "number theory" ]
null
null
Dante is engaged in a fight with "The Savior". Before he can fight it with his sword, he needs to break its shields. He has two guns, Ebony and Ivory, each of them is able to perform any non-negative number of shots. For every bullet that hits the shield, Ebony deals *a* units of damage while Ivory deals *b* units of damage. In order to break the shield Dante has to deal exactly *c* units of damage. Find out if this is possible.
The first line of the input contains three integers *a*, *b*, *c* (1<=≀<=*a*,<=*b*<=≀<=100,<=1<=≀<=*c*<=≀<=10<=000)Β β€” the number of units of damage dealt by Ebony gun and Ivory gun, and the total number of damage required to break the shield, respectively.
Print "Yes" (without quotes) if Dante can deal exactly *c* damage to the shield and "No" (without quotes) otherwise.
[ "4 6 15\n", "3 2 7\n", "6 11 6\n" ]
[ "No\n", "Yes\n", "Yes\n" ]
In the second sample, Dante can fire 1 bullet from Ebony and 2 from Ivory to deal exactly 1Β·3 + 2Β·2 = 7 damage. In the third sample, Dante can fire 1 bullet from ebony and no bullets from ivory to do 1Β·6 + 0Β·11 = 6 damage.
[ { "input": "4 6 15", "output": "No" }, { "input": "3 2 7", "output": "Yes" }, { "input": "6 11 6", "output": "Yes" }, { "input": "3 12 15", "output": "Yes" }, { "input": "5 5 10", "output": "Yes" }, { "input": "6 6 7", "output": "No" }, { "...
62
512,000
0
943
81
Sequence Formatting
[ "implementation", "strings" ]
B. Sequence Formatting
2
256
Polycarp is very careful. He even types numeric sequences carefully, unlike his classmates. If he sees a sequence without a space after the comma, with two spaces in a row, or when something else does not look neat, he rushes to correct it. For example, number sequence written like "1,2Β ,3,...,Β Β Β 10" will be corrected to "1,Β 2,Β 3,Β ...,Β 10". In this task you are given a string *s*, which is composed by a concatination of terms, each of which may be: - a positive integer of an arbitrary length (leading zeroes are not allowed), - a "comma" symbol (","), - a "space" symbol (" "), - "three dots" ("...", that is, exactly three points written one after another, also known as suspension points). Polycarp wants to add and remove spaces in the string *s* to ensure the following: - each comma is followed by exactly one space (if the comma is the last character in the string, this rule does not apply to it), - each "three dots" term is preceded by exactly one space (if the dots are at the beginning of the string, this rule does not apply to the term), - if two consecutive numbers were separated by spaces only (one or more), then exactly one of them should be left, - there should not be other spaces. Automate Polycarp's work and write a program that will process the given string *s*.
The input data contains a single string *s*. Its length is from 1 to 255 characters. The string *s* does not begin and end with a space. Its content matches the description given above.
Print the string *s* after it is processed. Your program's output should be exactly the same as the expected answer. It is permissible to end output line with a line-break character, and without it.
[ "1,2 ,3,..., 10\n", "1,,,4...5......6\n", "...,1,2,3,...\n" ]
[ "1, 2, 3, ..., 10\n", "1, , , 4 ...5 ... ...6\n", "..., 1, 2, 3, ...\n" ]
none
[ { "input": "1,2 ,3,..., 10", "output": "1, 2, 3, ..., 10" }, { "input": "1,,,4...5......6", "output": "1, , , 4 ...5 ... ...6" }, { "input": ",,,,,,,,,,,,,", "output": ", , , , , , , , , , , , ," }, { "input": "123456789", "output": "123456789" }, { "input": "...
184
0
0
944
805
Fake NP
[ "greedy", "math" ]
null
null
Tavak and Seyyed are good friends. Seyyed is very funny and he told Tavak to solve the following problem instead of longest-path. You are given *l* and *r*. For all integers from *l* to *r*, inclusive, we wrote down all of their integer divisors except 1. Find the integer that we wrote down the maximum number of times. Solve the problem to show that it's not a NP problem.
The first line contains two integers *l* and *r* (2<=≀<=*l*<=≀<=*r*<=≀<=109).
Print single integer, the integer that appears maximum number of times in the divisors. If there are multiple answers, print any of them.
[ "19 29\n", "3 6\n" ]
[ "2\n", "3\n" ]
Definition of a divisor: [https://www.mathsisfun.com/definitions/divisor-of-an-integer-.html](https://www.mathsisfun.com/definitions/divisor-of-an-integer-.html) The first example: from 19 to 29 these numbers are divisible by 2: {20, 22, 24, 26, 28}. The second example: from 3 to 6 these numbers are divisible by 3: {3, 6}.
[ { "input": "19 29", "output": "2" }, { "input": "3 6", "output": "2" }, { "input": "39 91", "output": "2" }, { "input": "76 134", "output": "2" }, { "input": "93 95", "output": "2" }, { "input": "17 35", "output": "2" }, { "input": "94 95",...
218
2,560,000
-1
946
292
Network Topology
[ "graphs", "implementation" ]
null
null
This problem uses a simplified network topology model, please read the problem statement carefully and use it as a formal document as you develop the solution. Polycarpus continues working as a system administrator in a large corporation. The computer network of this corporation consists of *n* computers, some of them are connected by a cable. The computers are indexed by integers from 1 to *n*. It's known that any two computers connected by cable directly or through other computers Polycarpus decided to find out the network's topology. A network topology is the way of describing the network configuration, the scheme that shows the location and the connections of network devices. Polycarpus knows three main network topologies: bus, ring and star. A bus is the topology that represents a shared cable with all computers connected with it. In the ring topology the cable connects each computer only with two other ones. A star is the topology where all computers of a network are connected to the single central node. Let's represent each of these network topologies as a connected non-directed graph. A bus is a connected graph that is the only path, that is, the graph where all nodes are connected with two other ones except for some two nodes that are the beginning and the end of the path. A ring is a connected graph, where all nodes are connected with two other ones. A star is a connected graph, where a single central node is singled out and connected with all other nodes. For clarifications, see the picture. You've got a connected non-directed graph that characterizes the computer network in Polycarpus' corporation. Help him find out, which topology type the given network is. If that is impossible to do, say that the network's topology is unknown.
The first line contains two space-separated integers *n* and *m* (4<=≀<=*n*<=≀<=105;Β 3<=≀<=*m*<=≀<=105) β€” the number of nodes and edges in the graph, correspondingly. Next *m* lines contain the description of the graph's edges. The *i*-th line contains a space-separated pair of integers *x**i*, *y**i* (1<=≀<=*x**i*,<=*y**i*<=≀<=*n*) β€” the numbers of nodes that are connected by the *i*-the edge. It is guaranteed that the given graph is connected. There is at most one edge between any two nodes. No edge connects a node with itself.
In a single line print the network topology name of the given graph. If the answer is the bus, print "bus topology" (without the quotes), if the answer is the ring, print "ring topology" (without the quotes), if the answer is the star, print "star topology" (without the quotes). If no answer fits, print "unknown topology" (without the quotes).
[ "4 3\n1 2\n2 3\n3 4\n", "4 4\n1 2\n2 3\n3 4\n4 1\n", "4 3\n1 2\n1 3\n1 4\n", "4 4\n1 2\n2 3\n3 1\n1 4\n" ]
[ "bus topology\n", "ring topology\n", "star topology\n", "unknown topology\n" ]
none
[ { "input": "4 3\n1 2\n2 3\n3 4", "output": "bus topology" }, { "input": "4 4\n1 2\n2 3\n3 4\n4 1", "output": "ring topology" }, { "input": "4 3\n1 2\n1 3\n1 4", "output": "star topology" }, { "input": "4 4\n1 2\n2 3\n3 1\n1 4", "output": "unknown topology" }, { "i...
654
716,800
3
947
387
George and Round
[ "brute force", "greedy", "two pointers" ]
null
null
George decided to prepare a Codesecrof round, so he has prepared *m* problems for the round. Let's number the problems with integers 1 through *m*. George estimates the *i*-th problem's complexity by integer *b**i*. To make the round good, he needs to put at least *n* problems there. Besides, he needs to have at least one problem with complexity exactly *a*1, at least one with complexity exactly *a*2, ..., and at least one with complexity exactly *a**n*. Of course, the round can also have problems with other complexities. George has a poor imagination. It's easier for him to make some already prepared problem simpler than to come up with a new one and prepare it. George is magnificent at simplifying problems. He can simplify any already prepared problem with complexity *c* to any positive integer complexity *d* (*c*<=β‰₯<=*d*), by changing limits on the input data. However, nothing is so simple. George understood that even if he simplifies some problems, he can run out of problems for a good round. That's why he decided to find out the minimum number of problems he needs to come up with in addition to the *m* he's prepared in order to make a good round. Note that George can come up with a new problem of any complexity.
The first line contains two integers *n* and *m* (1<=≀<=*n*,<=*m*<=≀<=3000) β€” the minimal number of problems in a good round and the number of problems George's prepared. The second line contains space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≀<=*a*1<=&lt;<=*a*2<=&lt;<=...<=&lt;<=*a**n*<=≀<=106) β€” the requirements for the complexity of the problems in a good round. The third line contains space-separated integers *b*1,<=*b*2,<=...,<=*b**m* (1<=≀<=*b*1<=≀<=*b*2...<=≀<=*b**m*<=≀<=106) β€” the complexities of the problems prepared by George.
Print a single integer β€” the answer to the problem.
[ "3 5\n1 2 3\n1 2 2 3 3\n", "3 5\n1 2 3\n1 1 1 1 1\n", "3 1\n2 3 4\n1\n" ]
[ "0\n", "2\n", "3\n" ]
In the first sample the set of the prepared problems meets the requirements for a good round. In the second sample, it is enough to come up with and prepare two problems with complexities 2 and 3 to get a good round. In the third sample it is very easy to get a good round if come up with and prepare extra problems with complexities: 2, 3, 4.
[ { "input": "3 5\n1 2 3\n1 2 2 3 3", "output": "0" }, { "input": "3 5\n1 2 3\n1 1 1 1 1", "output": "2" }, { "input": "3 1\n2 3 4\n1", "output": "3" }, { "input": "29 100\n20 32 41 67 72 155 331 382 399 412 465 470 484 511 515 529 616 637 679 715 733 763 826 843 862 903 925 97...
46
6,963,200
0
951
489
Given Length and Sum of Digits...
[ "dp", "greedy", "implementation" ]
null
null
You have a positive integer *m* and a non-negative integer *s*. Your task is to find the smallest and the largest of the numbers that have length *m* and sum of digits *s*. The required numbers should be non-negative integers written in the decimal base without leading zeroes.
The single line of the input contains a pair of integers *m*, *s* (1<=≀<=*m*<=≀<=100,<=0<=≀<=*s*<=≀<=900) β€” the length and the sum of the digits of the required numbers.
In the output print the pair of the required non-negative integer numbers β€” first the minimum possible number, then β€” the maximum possible number. If no numbers satisfying conditions required exist, print the pair of numbers "-1 -1" (without the quotes).
[ "2 15\n", "3 0\n" ]
[ "69 96\n", "-1 -1\n" ]
none
[ { "input": "2 15", "output": "69 96" }, { "input": "3 0", "output": "-1 -1" }, { "input": "2 1", "output": "10 10" }, { "input": "3 10", "output": "109 910" }, { "input": "100 100", "output": "1000000000000000000000000000000000000000000000000000000000000000000...
46
0
3
953
535
Tavas and SaDDas
[ "bitmasks", "brute force", "combinatorics", "implementation" ]
null
null
Once again Tavas started eating coffee mix without water! Keione told him that it smells awful, but he didn't stop doing that. That's why Keione told his smart friend, SaDDas to punish him! SaDDas took Tavas' headphones and told him: "If you solve the following problem, I'll return it to you." The problem is: You are given a lucky number *n*. Lucky numbers are the positive integers whose decimal representations contain only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not. If we sort all lucky numbers in increasing order, what's the 1-based index of *n*? Tavas is not as smart as SaDDas, so he asked you to do him a favor and solve this problem so he can have his headphones back.
The first and only line of input contains a lucky number *n* (1<=≀<=*n*<=≀<=109).
Print the index of *n* among all lucky numbers.
[ "4\n", "7\n", "77\n" ]
[ "1\n", "2\n", "6\n" ]
none
[ { "input": "4", "output": "1" }, { "input": "7", "output": "2" }, { "input": "77", "output": "6" }, { "input": "4", "output": "1" }, { "input": "474744", "output": "83" }, { "input": "777774", "output": "125" }, { "input": "447", "outpu...
62
0
3
955
691
Fashion in Berland
[ "implementation" ]
null
null
According to rules of the Berland fashion, a jacket should be fastened by all the buttons except only one, but not necessarily it should be the last one. Also if the jacket has only one button, it should be fastened, so the jacket will not swinging open. You are given a jacket with *n* buttons. Determine if it is fastened in a right way.
The first line contains integer *n* (1<=≀<=*n*<=≀<=1000) β€” the number of buttons on the jacket. The second line contains *n* integers *a**i* (0<=≀<=*a**i*<=≀<=1). The number *a**i*<==<=0 if the *i*-th button is not fastened. Otherwise *a**i*<==<=1.
In the only line print the word "YES" if the jacket is fastened in a right way. Otherwise print the word "NO".
[ "3\n1 0 1\n", "3\n1 0 0\n" ]
[ "YES\n", "NO\n" ]
none
[ { "input": "3\n1 0 1", "output": "YES" }, { "input": "3\n1 0 0", "output": "NO" }, { "input": "3\n1 1 0", "output": "YES" }, { "input": "3\n1 1 1", "output": "NO" }, { "input": "3\n0 0 1", "output": "NO" }, { "input": "3\n0 0 0", "output": "NO" }...
77
6,758,400
0
958
545
Equidistant String
[ "greedy" ]
null
null
Little Susie loves strings. Today she calculates distances between them. As Susie is a small girl after all, her strings contain only digits zero and one. She uses the definition of Hamming distance: We will define the distance between two strings *s* and *t* of the same length consisting of digits zero and one as the number of positions *i*, such that *s**i* isn't equal to *t**i*. As besides everything else Susie loves symmetry, she wants to find for two strings *s* and *t* of length *n* such string *p* of length *n*, that the distance from *p* to *s* was equal to the distance from *p* to *t*. It's time for Susie to go to bed, help her find such string *p* or state that it is impossible.
The first line contains string *s* of length *n*. The second line contains string *t* of length *n*. The length of string *n* is within range from 1 to 105. It is guaranteed that both strings contain only digits zero and one.
Print a string of length *n*, consisting of digits zero and one, that meets the problem statement. If no such string exist, print on a single line "impossible" (without the quotes). If there are multiple possible answers, print any of them.
[ "0001\n1011\n", "000\n111\n" ]
[ "0011\n", "impossible\n" ]
In the first sample different answers are possible, namely β€” 0010, 0011, 0110, 0111, 1000, 1001, 1100, 1101.
[ { "input": "0001\n1011", "output": "0011" }, { "input": "000\n111", "output": "impossible" }, { "input": "1010101011111110111111001111111111111111111111101101110111111111111110110110101011111110110111111101\n01011111110001000101000011000101010000000110000000000110110000011001000011101110...
31
0
0
959
719
Vitya in the Countryside
[ "implementation" ]
null
null
Every summer Vitya comes to visit his grandmother in the countryside. This summer, he got a huge wart. Every grandma knows that one should treat warts when the moon goes down. Thus, Vitya has to catch the moment when the moon is down. Moon cycle lasts 30 days. The size of the visible part of the moon (in Vitya's units) for each day is 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, and then cycle repeats, thus after the second 1 again goes 0. As there is no internet in the countryside, Vitya has been watching the moon for *n* consecutive days and for each of these days he wrote down the size of the visible part of the moon. Help him find out whether the moon will be up or down next day, or this cannot be determined by the data he has.
The first line of the input contains a single integer *n* (1<=≀<=*n*<=≀<=92)Β β€” the number of consecutive days Vitya was watching the size of the visible part of the moon. The second line contains *n* integers *a**i* (0<=≀<=*a**i*<=≀<=15)Β β€” Vitya's records. It's guaranteed that the input data is consistent.
If Vitya can be sure that the size of visible part of the moon on day *n*<=+<=1 will be less than the size of the visible part on day *n*, then print "DOWN" at the only line of the output. If he might be sure that the size of the visible part will increase, then print "UP". If it's impossible to determine what exactly will happen with the moon, print -1.
[ "5\n3 4 5 6 7\n", "7\n12 13 14 15 14 13 12\n", "1\n8\n" ]
[ "UP\n", "DOWN\n", "-1\n" ]
In the first sample, the size of the moon on the next day will be equal to 8, thus the answer is "UP". In the second sample, the size of the moon on the next day will be 11, thus the answer is "DOWN". In the third sample, there is no way to determine whether the size of the moon on the next day will be 7 or 9, thus the answer is -1.
[ { "input": "5\n3 4 5 6 7", "output": "UP" }, { "input": "7\n12 13 14 15 14 13 12", "output": "DOWN" }, { "input": "1\n8", "output": "-1" }, { "input": "44\n7 8 9 10 11 12 13 14 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 14 13 12 11 10", "out...
46
0
0
961
682
Alyona and Mex
[ "sortings" ]
null
null
Someone gave Alyona an array containing *n* positive integers *a*1,<=*a*2,<=...,<=*a**n*. In one operation, Alyona can choose any element of the array and decrease it, i.e. replace with any positive integer that is smaller than the current one. Alyona can repeat this operation as many times as she wants. In particular, she may not apply any operation to the array at all. Formally, after applying some operations Alyona will get an array of *n* positive integers *b*1,<=*b*2,<=...,<=*b**n* such that 1<=≀<=*b**i*<=≀<=*a**i* for every 1<=≀<=*i*<=≀<=*n*. Your task is to determine the maximum possible value of mex of this array. Mex of an array in this problem is the minimum positive integer that doesn't appear in this array. For example, mex of the array containing 1, 3 and 4 is equal to 2, while mex of the array containing 2, 3 and 2 is equal to 1.
The first line of the input contains a single integer *n* (1<=≀<=*n*<=≀<=100<=000)Β β€” the number of elements in the Alyona's array. The second line of the input contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≀<=*a**i*<=≀<=109)Β β€” the elements of the array.
Print one positive integerΒ β€” the maximum possible value of mex of the array after Alyona applies some (possibly none) operations.
[ "5\n1 3 3 3 6\n", "2\n2 1\n" ]
[ "5\n", "3\n" ]
In the first sample case if one will decrease the second element value to 2 and the fifth element value to 4 then the mex value of resulting array 1 2 3 3 4 will be equal to 5. To reach the answer to the second sample case one must not decrease any of the array elements.
[ { "input": "5\n1 3 3 3 6", "output": "5" }, { "input": "2\n2 1", "output": "3" }, { "input": "1\n1", "output": "2" }, { "input": "1\n1000000000", "output": "2" }, { "input": "1\n2", "output": "2" }, { "input": "2\n1 1", "output": "2" }, { "...
108
9,830,400
3
962
672
Different is Good
[ "constructive algorithms", "implementation", "strings" ]
null
null
A wise man told Kerem "Different is good" once, so Kerem wants all things in his life to be different. Kerem recently got a string *s* consisting of lowercase English letters. Since Kerem likes it when things are different, he wants all substrings of his string *s* to be distinct. Substring is a string formed by some number of consecutive characters of the string. For example, string "aba" has substrings "" (empty substring), "a", "b", "a", "ab", "ba", "aba". If string *s* has at least two equal substrings then Kerem will change characters at some positions to some other lowercase English letters. Changing characters is a very tiring job, so Kerem want to perform as few changes as possible. Your task is to find the minimum number of changes needed to make all the substrings of the given string distinct, or determine that it is impossible.
The first line of the input contains an integer *n* (1<=≀<=*n*<=≀<=100<=000)Β β€” the length of the string *s*. The second line contains the string *s* of length *n* consisting of only lowercase English letters.
If it's impossible to change the string *s* such that all its substring are distinct print -1. Otherwise print the minimum required number of changes.
[ "2\naa\n", "4\nkoko\n", "5\nmurat\n" ]
[ "1\n", "2\n", "0\n" ]
In the first sample one of the possible solutions is to change the first character to 'b'. In the second sample, one may change the first character to 'a' and second character to 'b', so the string becomes "abko".
[ { "input": "2\naa", "output": "1" }, { "input": "4\nkoko", "output": "2" }, { "input": "5\nmurat", "output": "0" }, { "input": "6\nacbead", "output": "1" }, { "input": "7\ncdaadad", "output": "4" }, { "input": "25\npeoaicnbisdocqofsqdpgobpn", "outp...
265
268,390,400
0
963
957
Tritonic Iridescence
[ "implementation" ]
null
null
Overlooking the captivating blend of myriads of vernal hues, Arkady the painter lays out a long, long canvas. Arkady has a sufficiently large amount of paint of three colours: cyan, magenta, and yellow. On the one-dimensional canvas split into *n* consecutive segments, each segment needs to be painted in one of the colours. Arkady has already painted some (possibly none or all) segments and passes the paintbrush to you. You are to determine whether there are at least two ways of colouring all the unpainted segments so that no two adjacent segments are of the same colour. Two ways are considered different if and only if a segment is painted in different colours in them.
The first line contains a single positive integer *n* (1<=≀<=*n*<=≀<=100)Β β€” the length of the canvas. The second line contains a string *s* of *n* characters, the *i*-th of which is either 'C' (denoting a segment painted in cyan), 'M' (denoting one painted in magenta), 'Y' (one painted in yellow), or '?' (an unpainted one).
If there are at least two different ways of painting, output "Yes"; otherwise output "No" (both without quotes). You can print each character in any case (upper or lower).
[ "5\nCY??Y\n", "5\nC?C?Y\n", "5\n?CYC?\n", "5\nC??MM\n", "3\nMMY\n" ]
[ "Yes\n", "Yes\n", "Yes\n", "No\n", "No\n" ]
For the first example, there are exactly two different ways of colouring: CYCMY and CYMCY. For the second example, there are also exactly two different ways of colouring: CMCMY and CYCMY. For the third example, there are four ways of colouring: MCYCM, MCYCY, YCYCM, and YCYCY. For the fourth example, no matter how the unpainted segments are coloured, the existing magenta segments will prevent the painting from satisfying the requirements. The similar is true for the fifth example.
[ { "input": "5\nCY??Y", "output": "Yes" }, { "input": "5\nC?C?Y", "output": "Yes" }, { "input": "5\n?CYC?", "output": "Yes" }, { "input": "5\nC??MM", "output": "No" }, { "input": "3\nMMY", "output": "No" }, { "input": "15\n??YYYYYY??YYYY?", "output"...
93
7,065,600
0
965
27
Tournament
[ "bitmasks", "brute force", "dfs and similar", "greedy" ]
B. Tournament
2
256
The tournament Β«Sleepyhead-2010Β» in the rapid falling asleep has just finished in Berland. *n* best participants from the country have participated in it. The tournament consists of games, each of them is a match between two participants. *n*Β·(*n*<=-<=1)<=/<=2 games were played during the tournament, and each participant had a match with each other participant. The rules of the game are quite simple β€” the participant who falls asleep first wins. The secretary made a record of each game in the form Β«*x**i* *y**i*Β», where *x**i* and *y**i* are the numbers of participants. The first number in each pair is a winner (i.e. *x**i* is a winner and *y**i* is a loser). There is no draws. Recently researches form the Β«Institute Of SleepΒ» have found that every person is characterized by a value *p**j* β€” the speed of falling asleep. The person who has lower speed wins. Every person has its own value *p**j*, constant during the life. It is known that all participants of the tournament have distinct speeds of falling asleep. Also it was found that the secretary made records about all the games except one. You are to find the result of the missing game.
The first line contains one integer *n* (3<=≀<=*n*<=≀<=50) β€” the number of participants. The following *n*Β·(*n*<=-<=1)<=/<=2<=-<=1 lines contain the results of the games. Each game is described in a single line by two integers *x**i*,<=*y**i* (1<=≀<=*x**i*,<=*y**i*<=≀<=*n*,<=*x**i*<=β‰ <=*y**i*), where *x**i* ΠΈ *y**i* are the numbers of the opponents in this game. It is known that during the tournament each of the *n* participants played *n*<=-<=1 games, one game with each other participant.
Output two integers *x* and *y* β€” the missing record. If there are several solutions, output any of them.
[ "4\n4 2\n4 1\n2 3\n2 1\n3 1\n" ]
[ "4 3\n" ]
none
[ { "input": "3\n3 2\n1 2", "output": "1 3" }, { "input": "4\n2 4\n3 4\n1 2\n1 4\n1 3", "output": "2 3" }, { "input": "5\n3 5\n2 5\n1 5\n1 4\n4 3\n1 3\n2 3\n4 5\n4 2", "output": "1 2" }, { "input": "6\n3 4\n3 5\n5 4\n1 2\n5 6\n2 6\n5 2\n3 6\n3 2\n4 6\n2 4\n1 3\n1 5\n1 4", "...
154
204,800
0
967
767
Snacktower
[ "data structures", "implementation" ]
null
null
According to an old legeng, a long time ago Ankh-Morpork residents did something wrong to miss Fortune, and she cursed them. She said that at some time *n* snacks of distinct sizes will fall on the city, and the residents should build a Snacktower of them by placing snacks one on another. Of course, big snacks should be at the bottom of the tower, while small snacks should be at the top. Years passed, and once different snacks started to fall onto the city, and the residents began to build the Snacktower. However, they faced some troubles. Each day exactly one snack fell onto the city, but their order was strange. So, at some days the residents weren't able to put the new stack on the top of the Snacktower: they had to wait until all the bigger snacks fell. Of course, in order to not to anger miss Fortune again, the residents placed each snack on the top of the tower immediately as they could do it. Write a program that models the behavior of Ankh-Morpork residents.
The first line contains single integer *n* (1<=≀<=*n*<=≀<=100<=000)Β β€” the total number of snacks. The second line contains *n* integers, the *i*-th of them equals the size of the snack which fell on the *i*-th day. Sizes are distinct integers from 1 to *n*.
Print *n* lines. On the *i*-th of them print the sizes of the snacks which the residents placed on the top of the Snacktower on the *i*-th day in the order they will do that. If no snack is placed on some day, leave the corresponding line empty.
[ "3\n3 1 2\n", "5\n4 5 1 2 3\n" ]
[ "3\nΒ \n2 1", "5 4\nΒ \nΒ \n3 2 1\n" ]
In the example a snack of size 3 fell on the first day, and the residents immediately placed it. On the second day a snack of size 1 fell, and the residents weren't able to place it because they were missing the snack of size 2. On the third day a snack of size 2 fell, and the residents immediately placed it. Right after that they placed the snack of size 1 which had fallen before.
[ { "input": "3\n3 1 2", "output": "3 \n\n2 1 " }, { "input": "5\n4 5 1 2 3", "output": "5 4 \n\n\n3 2 1 " }, { "input": "1\n1", "output": "1 " }, { "input": "2\n1 2", "output": "2 1 " }, { "input": "10\n5 1 6 2 8 3 4 10 9 7", "output": "10 \n9 8 \n7 6 5 4 3 2 1...
31
0
0
968
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) β€” 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) β€” 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...
62
0
3
969
245
System Administrator
[ "implementation" ]
null
null
Polycarpus is a system administrator. There are two servers under his strict guidance β€” *a* and *b*. To stay informed about the servers' performance, Polycarpus executes commands "ping a" and "ping b". Each ping command sends exactly ten packets to the server specified in the argument of the command. Executing a program results in two integers *x* and *y* (*x*<=+<=*y*<==<=10;Β *x*,<=*y*<=β‰₯<=0). These numbers mean that *x* packets successfully reached the corresponding server through the network and *y* packets were lost. Today Polycarpus has performed overall *n* ping commands during his workday. Now for each server Polycarpus wants to know whether the server is "alive" or not. Polycarpus thinks that the server is "alive", if at least half of the packets that we send to this server reached it successfully along the network. Help Polycarpus, determine for each server, whether it is "alive" or not by the given commands and their results.
The first line contains a single integer *n* (2<=≀<=*n*<=≀<=1000) β€” the number of commands Polycarpus has fulfilled. Each of the following *n* lines contains three integers β€” the description of the commands. The *i*-th of these lines contains three space-separated integers *t**i*, *x**i*, *y**i* (1<=≀<=*t**i*<=≀<=2;Β *x**i*,<=*y**i*<=β‰₯<=0;Β *x**i*<=+<=*y**i*<==<=10). If *t**i*<==<=1, then the *i*-th command is "ping a", otherwise the *i*-th command is "ping b". Numbers *x**i*, *y**i* represent the result of executing this command, that is, *x**i* packets reached the corresponding server successfully and *y**i* packets were lost. It is guaranteed that the input has at least one "ping a" command and at least one "ping b" command.
In the first line print string "LIVE" (without the quotes) if server *a* is "alive", otherwise print "DEAD" (without the quotes). In the second line print the state of server *b* in the similar format.
[ "2\n1 5 5\n2 6 4\n", "3\n1 0 10\n2 0 10\n1 10 0\n" ]
[ "LIVE\nLIVE\n", "LIVE\nDEAD\n" ]
Consider the first test case. There 10 packets were sent to server *a*, 5 of them reached it. Therefore, at least half of all packets sent to this server successfully reached it through the network. Overall there were 10 packets sent to server *b*, 6 of them reached it. Therefore, at least half of all packets sent to this server successfully reached it through the network. Consider the second test case. There were overall 20 packages sent to server *a*, 10 of them reached it. Therefore, at least half of all packets sent to this server successfully reached it through the network. Overall 10 packets were sent to server *b*, 0 of them reached it. Therefore, less than half of all packets sent to this server successfully reached it through the network.
[ { "input": "2\n1 5 5\n2 6 4", "output": "LIVE\nLIVE" }, { "input": "3\n1 0 10\n2 0 10\n1 10 0", "output": "LIVE\nDEAD" }, { "input": "10\n1 3 7\n2 4 6\n1 2 8\n2 5 5\n2 10 0\n2 10 0\n1 8 2\n2 2 8\n2 10 0\n1 1 9", "output": "DEAD\nLIVE" }, { "input": "11\n1 8 2\n1 6 4\n1 9 1\n1...
186
1,638,400
3
971
976
Nested Segments
[ "greedy", "implementation", "sortings" ]
null
null
You are given a sequence *a*1,<=*a*2,<=...,<=*a**n* of one-dimensional segments numbered 1 through *n*. Your task is to find two distinct indices *i* and *j* such that segment *a**i* lies within segment *a**j*. Segment [*l*1,<=*r*1] lies within segment [*l*2,<=*r*2] iff *l*1<=β‰₯<=*l*2 and *r*1<=≀<=*r*2. Print indices *i* and *j*. If there are multiple answers, print any of them. If no answer exists, print -1 -1.
The first line contains one integer *n* (1<=≀<=*n*<=≀<=3Β·105) β€” the number of segments. Each of the next *n* lines contains two integers *l**i* and *r**i* (1<=≀<=*l**i*<=≀<=*r**i*<=≀<=109) β€” the *i*-th segment.
Print two distinct indices *i* and *j* such that segment *a**i* lies within segment *a**j*. If there are multiple answers, print any of them. If no answer exists, print -1 -1.
[ "5\n1 10\n2 9\n3 9\n2 3\n2 9\n", "3\n1 5\n2 6\n6 20\n" ]
[ "2 1\n", "-1 -1\n" ]
In the first example the following pairs are considered correct: - (2, 1), (3, 1), (4, 1), (5, 1) β€” not even touching borders; - (3, 2), (4, 2), (3, 5), (4, 5) β€” touch one border; - (5, 2), (2, 5) β€” match exactly.
[ { "input": "5\n1 10\n2 9\n3 9\n2 3\n2 9", "output": "2 1" }, { "input": "3\n1 5\n2 6\n6 20", "output": "-1 -1" }, { "input": "1\n1 1000000000", "output": "-1 -1" }, { "input": "2\n1 1000000000\n1 1000000000", "output": "2 1" }, { "input": "2\n1 1000000000\n5000000...
0
0
-1
972
725
Food on the Plane
[ "implementation", "math" ]
null
null
A new airplane SuperPuperJet has an infinite number of rows, numbered with positive integers starting with 1 from cockpit to tail. There are six seats in each row, denoted with letters from 'a' to 'f'. Seats 'a', 'b' and 'c' are located to the left of an aisle (if one looks in the direction of the cockpit), while seats 'd', 'e' and 'f' are located to the right. Seats 'a' and 'f' are located near the windows, while seats 'c' and 'd' are located near the aisle. Β  It's lunch time and two flight attendants have just started to serve food. They move from the first rows to the tail, always maintaining a distance of two rows from each other because of the food trolley. Thus, at the beginning the first attendant serves row 1 while the second attendant serves row 3. When both rows are done they move one row forward: the first attendant serves row 2 while the second attendant serves row 4. Then they move three rows forward and the first attendant serves row 5 while the second attendant serves row 7. Then they move one row forward again and so on. Flight attendants work with the same speed: it takes exactly 1 second to serve one passenger and 1 second to move one row forward. Each attendant first serves the passengers on the seats to the right of the aisle and then serves passengers on the seats to the left of the aisle (if one looks in the direction of the cockpit). Moreover, they always serve passengers in order from the window to the aisle. Thus, the first passenger to receive food in each row is located in seat 'f', and the last oneΒ β€” in seat 'c'. Assume that all seats are occupied. Vasya has seat *s* in row *n* and wants to know how many seconds will pass before he gets his lunch.
The only line of input contains a description of Vasya's seat in the format *ns*, where *n* (1<=≀<=*n*<=≀<=1018) is the index of the row and *s* is the seat in this row, denoted as letter from 'a' to 'f'. The index of the row and the seat are not separated by a space.
Print one integerΒ β€” the number of seconds Vasya has to wait until he gets his lunch.
[ "1f\n", "2d\n", "4a\n", "5e\n" ]
[ "1\n", "10\n", "11\n", "18\n" ]
In the first sample, the first flight attendant serves Vasya first, so Vasya gets his lunch after 1 second. In the second sample, the flight attendants will spend 6 seconds to serve everyone in the rows 1 and 3, then they will move one row forward in 1 second. As they first serve seats located to the right of the aisle in order from window to aisle, Vasya has to wait 3 more seconds. The total is 6 + 1 + 3 = 10.
[ { "input": "1f", "output": "1" }, { "input": "2d", "output": "10" }, { "input": "4a", "output": "11" }, { "input": "5e", "output": "18" }, { "input": "2c", "output": "13" }, { "input": "1b", "output": "5" }, { "input": "1000000000000000000d...
46
0
0
975
632
Grandma Laura and Apples
[]
null
null
Grandma Laura came to the market to sell some apples. During the day she sold all the apples she had. But grandma is old, so she forgot how many apples she had brought to the market. She precisely remembers she had *n* buyers and each of them bought exactly half of the apples she had at the moment of the purchase and also she gave a half of an apple to some of them as a gift (if the number of apples at the moment of purchase was odd), until she sold all the apples she had. So each buyer took some integral positive number of apples, but maybe he didn't pay for a half of an apple (if the number of apples at the moment of the purchase was odd). For each buyer grandma remembers if she gave a half of an apple as a gift or not. The cost of an apple is *p* (the number *p* is even). Print the total money grandma should have at the end of the day to check if some buyers cheated her.
The first line contains two integers *n* and *p* (1<=≀<=*n*<=≀<=40,<=2<=≀<=*p*<=≀<=1000) β€” the number of the buyers and the cost of one apple. It is guaranteed that the number *p* is even. The next *n* lines contains the description of buyers. Each buyer is described with the string half if he simply bought half of the apples and with the string halfplus if grandma also gave him a half of an apple as a gift. It is guaranteed that grandma has at least one apple at the start of the day and she has no apples at the end of the day.
Print the only integer *a* β€” the total money grandma should have at the end of the day. Note that the answer can be too large, 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.
[ "2 10\nhalf\nhalfplus\n", "3 10\nhalfplus\nhalfplus\nhalfplus\n" ]
[ "15\n", "55\n" ]
In the first sample at the start of the day the grandma had two apples. First she sold one apple and then she sold a half of the second apple and gave a half of the second apple as a present to the second buyer.
[ { "input": "2 10\nhalf\nhalfplus", "output": "15" }, { "input": "3 10\nhalfplus\nhalfplus\nhalfplus", "output": "55" }, { "input": "10 328\nhalf\nhalfplus\nhalfplus\nhalf\nhalfplus\nhalf\nhalf\nhalf\nhalfplus\nhalfplus", "output": "258300" }, { "input": "1 2\nhalfplus", "...
77
0
0
978
39
Cubical Planet
[ "math" ]
D. Cubical Planet
2
64
You can find anything whatsoever in our Galaxy! A cubical planet goes round an icosahedral star. Let us introduce a system of axes so that the edges of the cubical planet are parallel to the coordinate axes and two opposite vertices lay in the points (0,<=0,<=0) and (1,<=1,<=1). Two flies live on the planet. At the moment they are sitting on two different vertices of the cubical planet. Your task is to determine whether they see each other or not. The flies see each other when the vertices they occupy lie on the same face of the cube.
The first line contains three space-separated integers (0 or 1) β€” the coordinates of the first fly, the second line analogously contains the coordinates of the second fly.
Output "YES" (without quotes) if the flies see each other. Otherwise, output "NO".
[ "0 0 0\n0 1 0\n", "1 1 0\n0 1 0\n", "0 0 0\n1 1 1\n" ]
[ "YES\n", "YES\n", "NO\n" ]
none
[ { "input": "0 0 0\n0 1 0", "output": "YES" }, { "input": "1 1 0\n0 1 0", "output": "YES" }, { "input": "0 0 0\n1 1 1", "output": "NO" }, { "input": "0 0 0\n1 0 0", "output": "YES" }, { "input": "0 0 0\n0 1 0", "output": "YES" }, { "input": "0 0 0\n1 1 ...
124
0
0
979
884
Japanese Crosswords Strike Back
[ "implementation" ]
null
null
A one-dimensional Japanese crossword can be represented as a binary string of length *x*. An encoding of this crossword is an array *a* of size *n*, where *n* is the number of segments formed completely of 1's, and *a**i* is the length of *i*-th segment. No two segments touch or intersect. For example: - If *x*<==<=6 and the crossword is 111011, then its encoding is an array {3,<=2}; - If *x*<==<=8 and the crossword is 01101010, then its encoding is an array {2,<=1,<=1}; - If *x*<==<=5 and the crossword is 11111, then its encoding is an array {5}; - If *x*<==<=5 and the crossword is 00000, then its encoding is an empty array. Mishka wants to create a new one-dimensional Japanese crossword. He has already picked the length and the encoding for this crossword. And now he needs to check if there is exactly one crossword such that its length and encoding are equal to the length and encoding he picked. Help him to check it!
The first line contains two integer numbers *n* and *x* (1<=≀<=*n*<=≀<=100000, 1<=≀<=*x*<=≀<=109) β€” the number of elements in the encoding and the length of the crossword Mishka picked. The second line contains *n* integer numbers *a*1, *a*2, ..., *a**n* (1<=≀<=*a**i*<=≀<=10000) β€” the encoding.
Print YES if there exists exaclty one crossword with chosen length and encoding. Otherwise, print NO.
[ "2 4\n1 3\n", "3 10\n3 3 2\n", "2 10\n1 3\n" ]
[ "NO\n", "YES\n", "NO\n" ]
none
[ { "input": "2 4\n1 3", "output": "NO" }, { "input": "3 10\n3 3 2", "output": "YES" }, { "input": "2 10\n1 3", "output": "NO" }, { "input": "1 1\n1", "output": "YES" }, { "input": "1 10\n10", "output": "YES" }, { "input": "1 10000\n10000", "output":...
77
7,372,800
3
980
266
Stones on the Table
[ "implementation" ]
null
null
There are *n* stones on the table in a row, each of them can be red, green or blue. Count the minimum number of stones to take from the table so that any two neighboring stones had different colors. Stones in a row are considered neighboring if there are no other stones between them.
The first line contains integer *n* (1<=≀<=*n*<=≀<=50) β€” the number of stones on the table. The next line contains string *s*, which represents the colors of the stones. We'll consider the stones in the row numbered from 1 to *n* from left to right. Then the *i*-th character *s* equals "R", if the *i*-th stone is red, "G", if it's green and "B", if it's blue.
Print a single integer β€” the answer to the problem.
[ "3\nRRG\n", "5\nRRRRR\n", "4\nBRBG\n" ]
[ "1\n", "4\n", "0\n" ]
none
[ { "input": "3\nRRG", "output": "1" }, { "input": "5\nRRRRR", "output": "4" }, { "input": "4\nBRBG", "output": "0" }, { "input": "1\nB", "output": "0" }, { "input": "2\nBG", "output": "0" }, { "input": "3\nBGB", "output": "0" }, { "input": "...
60
0
-1
981
315
Sereja and Array
[ "implementation" ]
null
null
Sereja has got an array, consisting of *n* integers, *a*1,<=*a*2,<=...,<=*a**n*. Sereja is an active boy, so he is now going to complete *m* operations. Each operation will have one of the three forms: 1. Make *v**i*-th array element equal to *x**i*. In other words, perform the assignment *a**v**i*<==<=*x**i*. 1. Increase each array element by *y**i*. In other words, perform *n* assignments *a**i*<==<=*a**i*<=+<=*y**i* (1<=≀<=*i*<=≀<=*n*). 1. Take a piece of paper and write out the *q**i*-th array element. That is, the element *a**q**i*. Help Sereja, complete all his operations.
The first line contains integers *n*, *m* (1<=≀<=*n*,<=*m*<=≀<=105). The second line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≀<=*a**i*<=≀<=109) β€” the original array. Next *m* lines describe operations, the *i*-th line describes the *i*-th operation. The first number in the *i*-th line is integer *t**i* (1<=≀<=*t**i*<=≀<=3) that represents the operation type. If *t**i*<==<=1, then it is followed by two integers *v**i* and *x**i*, (1<=≀<=*v**i*<=≀<=*n*,<=1<=≀<=*x**i*<=≀<=109). If *t**i*<==<=2, then it is followed by integer *y**i* (1<=≀<=*y**i*<=≀<=104). And if *t**i*<==<=3, then it is followed by integer *q**i* (1<=≀<=*q**i*<=≀<=*n*).
For each third type operation print value *a**q**i*. Print the values in the order, in which the corresponding queries follow in the input.
[ "10 11\n1 2 3 4 5 6 7 8 9 10\n3 2\n3 9\n2 10\n3 1\n3 10\n1 1 10\n2 10\n2 10\n3 1\n3 10\n3 9\n" ]
[ "2\n9\n11\n20\n30\n40\n39\n" ]
none
[ { "input": "10 11\n1 2 3 4 5 6 7 8 9 10\n3 2\n3 9\n2 10\n3 1\n3 10\n1 1 10\n2 10\n2 10\n3 1\n3 10\n3 9", "output": "2\n9\n11\n20\n30\n40\n39" }, { "input": "1 3\n1\n1 1 2\n2 1\n3 1", "output": "3" }, { "input": "1 1\n1\n3 1", "output": "1" }, { "input": "6 6\n202714501 613423...
1,000
9,216,000
0
982
384
Coder
[ "implementation" ]
null
null
Iahub likes chess very much. He even invented a new chess piece named Coder. A Coder can move (and attack) one square horizontally or vertically. More precisely, if the Coder is located at position (*x*,<=*y*), he can move to (or attack) positions (*x*<=+<=1,<=*y*), (*x*–1,<=*y*), (*x*,<=*y*<=+<=1) and (*x*,<=*y*–1). Iahub wants to know how many Coders can be placed on an *n*<=Γ—<=*n* chessboard, so that no Coder attacks any other Coder.
The first line contains an integer *n* (1<=≀<=*n*<=≀<=1000).
On the first line print an integer, the maximum number of Coders that can be placed on the chessboard. On each of the next *n* lines print *n* characters, describing the configuration of the Coders. For an empty cell print an '.', and for a Coder print a 'C'. If there are multiple correct answers, you can print any.
[ "2\n" ]
[ "2\nC.\n.C\n" ]
none
[ { "input": "2", "output": "2\nC.\n.C" }, { "input": "3", "output": "5\nC.C\n.C.\nC.C" }, { "input": "4", "output": "8\nC.C.\n.C.C\nC.C.\n.C.C" }, { "input": "10", "output": "50\nC.C.C.C.C.\n.C.C.C.C.C\nC.C.C.C.C.\n.C.C.C.C.C\nC.C.C.C.C.\n.C.C.C.C.C\nC.C.C.C.C.\n.C.C.C.C.C...
1,000
10,854,400
0
984
236
Boy or Girl
[ "brute force", "implementation", "strings" ]
null
null
Those days, many boys use beautiful girls' photos as avatars in forums. So it is pretty hard to tell the gender of a user at the first glance. Last year, our hero went to a forum and had a nice chat with a beauty (he thought so). After that they talked very often and eventually they became a couple in the network. But yesterday, he came to see "her" in the real world and found out "she" is actually a very strong man! Our hero is very sad and he is too tired to love again now. So he came up with a way to recognize users' genders by their user names. This is his method: if the number of distinct characters in one's user name is odd, then he is a male, otherwise she is a female. You are given the string that denotes the user name, please help our hero to determine the gender of this user by his method.
The first line contains a non-empty string, that contains only lowercase English letters β€” the user name. This string contains at most 100 letters.
If it is a female by our hero's method, print "CHAT WITH HER!" (without the quotes), otherwise, print "IGNORE HIM!" (without the quotes).
[ "wjmzbmr\n", "xiaodao\n", "sevenkplus\n" ]
[ "CHAT WITH HER!\n", "IGNORE HIM!\n", "CHAT WITH HER!\n" ]
For the first example. There are 6 distinct characters in "wjmzbmr". These characters are: "w", "j", "m", "z", "b", "r". So wjmzbmr is a female and you should print "CHAT WITH HER!".
[ { "input": "wjmzbmr", "output": "CHAT WITH HER!" }, { "input": "xiaodao", "output": "IGNORE HIM!" }, { "input": "sevenkplus", "output": "CHAT WITH HER!" }, { "input": "pezu", "output": "CHAT WITH HER!" }, { "input": "wnemlgppy", "output": "CHAT WITH HER!" },...
92
0
3
985
578
"Or" Game
[ "brute force", "greedy" ]
null
null
You are given *n* numbers *a*1,<=*a*2,<=...,<=*a**n*. You can perform at most *k* operations. For each operation you can multiply one of the numbers by *x*. We want to make as large as possible, where denotes the bitwise OR. Find the maximum possible value of after performing at most *k* operations optimally.
The first line contains three integers *n*, *k* and *x* (1<=≀<=*n*<=≀<=200<=000, 1<=≀<=*k*<=≀<=10, 2<=≀<=*x*<=≀<=8). The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (0<=≀<=*a**i*<=≀<=109).
Output the maximum value of a bitwise OR of sequence elements after performing operations.
[ "3 1 2\n1 1 1\n", "4 2 3\n1 2 4 8\n" ]
[ "3\n", "79\n" ]
For the first sample, any possible choice of doing one operation will result the same three numbers 1, 1, 2 so the result is <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/1ee73b671ed4bc53f2f96ed1a85fd98388e1712b.png" style="max-width: 100.0%;max-height: 100.0%;"/>. For the second sample if we multiply 8 by 3 two times we'll get 72. In this case the numbers will become 1, 2, 4, 72 so the OR value will be 79 and is the largest possible result.
[ { "input": "3 1 2\n1 1 1", "output": "3" }, { "input": "4 2 3\n1 2 4 8", "output": "79" }, { "input": "2 1 2\n12 9", "output": "30" }, { "input": "2 1 2\n12 7", "output": "31" }, { "input": "3 1 3\n3 2 0", "output": "11" }, { "input": "5 10 8\n10000000...
93
0
0
987
334
Candy Bags
[ "implementation" ]
null
null
Gerald has *n* younger brothers and their number happens to be even. One day he bought *n*2 candy bags. One bag has one candy, one bag has two candies, one bag has three candies and so on. In fact, for each integer *k* from 1 to *n*2 he has exactly one bag with *k* candies. Help him give *n* bags of candies to each brother so that all brothers got the same number of candies.
The single line contains a single integer *n* (*n* is even, 2<=≀<=*n*<=≀<=100) β€” the number of Gerald's brothers.
Let's assume that Gerald indexes his brothers with numbers from 1 to *n*. You need to print *n* lines, on the *i*-th line print *n* integers β€” the numbers of candies in the bags for the *i*-th brother. Naturally, all these numbers should be distinct and be within limits from 1 to *n*2. You can print the numbers in the lines in any order. It is guaranteed that the solution exists at the given limits.
[ "2\n" ]
[ "1 4\n2 3\n" ]
The sample shows Gerald's actions if he has two brothers. In this case, his bags contain 1, 2, 3 and 4 candies. He can give the bags with 1 and 4 candies to one brother and the bags with 2 and 3 to the other brother.
[ { "input": "2", "output": "1 4\n2 3" }, { "input": "4", "output": "1 16 2 15\n3 14 4 13\n5 12 6 11\n7 10 8 9" }, { "input": "6", "output": "1 36 2 35 3 34\n4 33 5 32 6 31\n7 30 8 29 9 28\n10 27 11 26 12 25\n13 24 14 23 15 22\n16 21 17 20 18 19" }, { "input": "8", "output"...
218
6,963,200
3
988
920
Water The Garden
[ "implementation" ]
null
null
It is winter now, and Max decided it's about time he watered the garden. The garden can be represented as *n* consecutive garden beds, numbered from 1 to *n*. *k* beds contain water taps (*i*-th tap is located in the bed *x**i*), which, if turned on, start delivering water to neighbouring beds. If the tap on the bed *x**i* is turned on, then after one second has passed, the bed *x**i* will be watered; after two seconds have passed, the beds from the segment [*x**i*<=-<=1,<=*x**i*<=+<=1] will be watered (if they exist); after *j* seconds have passed (*j* is an integer number), the beds from the segment [*x**i*<=-<=(*j*<=-<=1),<=*x**i*<=+<=(*j*<=-<=1)] will be watered (if they exist). Nothing changes during the seconds, so, for example, we can't say that the segment [*x**i*<=-<=2.5,<=*x**i*<=+<=2.5] will be watered after 2.5 seconds have passed; only the segment [*x**i*<=-<=2,<=*x**i*<=+<=2] will be watered at that moment. Max wants to turn on all the water taps at the same moment, and now he wonders, what is the minimum number of seconds that have to pass after he turns on some taps until the whole garden is watered. Help him to find the answer!
The first line contains one integer *t* β€” the number of test cases to solve (1<=≀<=*t*<=≀<=200). Then *t* test cases follow. The first line of each test case contains two integers *n* and *k* (1<=≀<=*n*<=≀<=200, 1<=≀<=*k*<=≀<=*n*) β€” the number of garden beds and water taps, respectively. Next line contains *k* integers *x**i* (1<=≀<=*x**i*<=≀<=*n*) β€” the location of *i*-th water tap. It is guaranteed that for each condition *x**i*<=-<=1<=&lt;<=*x**i* holds. It is guaranteed that the sum of *n* over all test cases doesn't exceed 200. Note that in hacks you have to set *t*<==<=1.
For each test case print one integer β€” the minimum number of seconds that have to pass after Max turns on some of the water taps, until the whole garden is watered.
[ "3\n5 1\n3\n3 3\n1 2 3\n4 1\n1\n" ]
[ "3\n1\n4\n" ]
The first example consists of 3 tests: 1. There are 5 garden beds, and a water tap in the bed 3. If we turn it on, then after 1 second passes, only bed 3 will be watered; after 2 seconds pass, beds [1, 3] will be watered, and after 3 seconds pass, everything will be watered. 1. There are 3 garden beds, and there is a water tap in each one. If we turn all of them on, then everything will be watered after 1 second passes. 1. There are 4 garden beds, and only one tap in the bed 1. It will take 4 seconds to water, for example, bed 4.
[ { "input": "3\n5 1\n3\n3 3\n1 2 3\n4 1\n1", "output": "3\n1\n4" }, { "input": "26\n1 1\n1\n2 1\n2\n2 1\n1\n2 2\n1 2\n3 1\n3\n3 1\n2\n3 2\n2 3\n3 1\n1\n3 2\n1 3\n3 2\n1 2\n3 3\n1 2 3\n4 1\n4\n4 1\n3\n4 2\n3 4\n4 1\n2\n4 2\n2 4\n4 2\n2 3\n4 3\n2 3 4\n4 1\n1\n4 2\n1 4\n4 2\n1 3\n4 3\n1 3 4\n4 2\n1 2\n4...
62
19,968,000
0
990
488
Giga Tower
[ "brute force" ]
null
null
Giga Tower is the tallest and deepest building in Cyberland. There are 17<=777<=777<=777 floors, numbered from <=-<=8<=888<=888<=888 to 8<=888<=888<=888. In particular, there is floor 0 between floor <=-<=1 and floor 1. Every day, thousands of tourists come to this place to enjoy the wonderful view. In Cyberland, it is believed that the number "8" is a lucky number (that's why Giga Tower has 8<=888<=888<=888 floors above the ground), and, an integer is lucky, if and only if its decimal notation contains at least one digit "8". For example, 8,<=<=-<=180,<=808 are all lucky while 42,<=<=-<=10 are not. In the Giga Tower, if you write code at a floor with lucky floor number, good luck will always be with you (Well, this round is #278, also lucky, huh?). Tourist Henry goes to the tower to seek good luck. Now he is at the floor numbered *a*. He wants to find the minimum positive integer *b*, such that, if he walks *b* floors higher, he will arrive at a floor with a lucky number.
The only line of input contains an integer *a* (<=-<=109<=≀<=*a*<=≀<=109).
Print the minimum *b* in a line.
[ "179\n", "-1\n", "18\n" ]
[ "1\n", "9\n", "10\n" ]
For the first sample, he has to arrive at the floor numbered 180. For the second sample, he will arrive at 8. Note that *b* should be positive, so the answer for the third sample is 10, not 0.
[ { "input": "179", "output": "1" }, { "input": "-1", "output": "9" }, { "input": "18", "output": "10" }, { "input": "-410058385", "output": "1" }, { "input": "-586825624", "output": "1" }, { "input": "852318890", "output": "1" }, { "input": ...
46
0
0
991
680
Bear and Finding Criminals
[ "constructive algorithms", "implementation" ]
null
null
There are *n* cities in Bearland, numbered 1 through *n*. Cities are arranged in one long row. The distance between cities *i* and *j* is equal to |*i*<=-<=*j*|. Limak is a police officer. He lives in a city *a*. His job is to catch criminals. It's hard because he doesn't know in which cities criminals are. Though, he knows that there is at most one criminal in each city. Limak is going to use a BCD (Bear Criminal Detector). The BCD will tell Limak how many criminals there are for every distance from a city *a*. After that, Limak can catch a criminal in each city for which he is sure that there must be a criminal. You know in which cities criminals are. Count the number of criminals Limak will catch, after he uses the BCD.
The first line of the input contains two integers *n* and *a* (1<=≀<=*a*<=≀<=*n*<=≀<=100)Β β€” the number of cities and the index of city where Limak lives. The second line contains *n* integers *t*1,<=*t*2,<=...,<=*t**n* (0<=≀<=*t**i*<=≀<=1). There are *t**i* criminals in the *i*-th city.
Print the number of criminals Limak will catch.
[ "6 3\n1 1 1 0 1 0\n", "5 2\n0 0 0 1 0\n" ]
[ "3\n", "1\n" ]
In the first sample, there are six cities and Limak lives in the third one (blue arrow below). Criminals are in cities marked red. Using the BCD gives Limak the following information: - There is one criminal at distance 0 from the third cityΒ β€” Limak is sure that this criminal is exactly in the third city. - There is one criminal at distance 1 from the third cityΒ β€” Limak doesn't know if a criminal is in the second or fourth city. - There are two criminals at distance 2 from the third cityΒ β€” Limak is sure that there is one criminal in the first city and one in the fifth city. - There are zero criminals for every greater distance. So, Limak will catch criminals in cities 1, 3 and 5, that is 3 criminals in total. In the second sample (drawing below), the BCD gives Limak the information that there is one criminal at distance 2 from Limak's city. There is only one city at distance 2 so Limak is sure where a criminal is.
[ { "input": "6 3\n1 1 1 0 1 0", "output": "3" }, { "input": "5 2\n0 0 0 1 0", "output": "1" }, { "input": "1 1\n1", "output": "1" }, { "input": "1 1\n0", "output": "0" }, { "input": "9 3\n1 1 1 1 1 1 1 1 0", "output": "8" }, { "input": "9 5\n1 0 1 0 1 0...
46
0
0
995
449
Jzzhu and Cities
[ "graphs", "greedy", "shortest paths" ]
null
null
Jzzhu is the president of country A. There are *n* cities numbered from 1 to *n* in his country. City 1 is the capital of A. Also there are *m* roads connecting the cities. One can go from city *u**i* to *v**i* (and vise versa) using the *i*-th road, the length of this road is *x**i*. Finally, there are *k* train routes in the country. One can use the *i*-th train route to go from capital of the country to city *s**i* (and vise versa), the length of this route is *y**i*. Jzzhu doesn't want to waste the money of the country, so he is going to close some of the train routes. Please tell Jzzhu the maximum number of the train routes which can be closed under the following condition: the length of the shortest path from every city to the capital mustn't change.
The first line contains three integers *n*,<=*m*,<=*k* (2<=≀<=*n*<=≀<=105;Β 1<=≀<=*m*<=≀<=3Β·105;Β 1<=≀<=*k*<=≀<=105). Each of the next *m* lines contains three integers *u**i*,<=*v**i*,<=*x**i* (1<=≀<=*u**i*,<=*v**i*<=≀<=*n*;Β *u**i*<=β‰ <=*v**i*;Β 1<=≀<=*x**i*<=≀<=109). Each of the next *k* lines contains two integers *s**i* and *y**i* (2<=≀<=*s**i*<=≀<=*n*;Β 1<=≀<=*y**i*<=≀<=109). It is guaranteed that there is at least one way from every city to the capital. Note, that there can be multiple roads between two cities. Also, there can be multiple routes going to the same city from the capital.
Output a single integer representing the maximum number of the train routes which can be closed.
[ "5 5 3\n1 2 1\n2 3 2\n1 3 3\n3 4 4\n1 5 5\n3 5\n4 5\n5 5\n", "2 2 3\n1 2 2\n2 1 3\n2 1\n2 2\n2 3\n" ]
[ "2\n", "2\n" ]
none
[ { "input": "5 5 3\n1 2 1\n2 3 2\n1 3 3\n3 4 4\n1 5 5\n3 5\n4 5\n5 5", "output": "2" }, { "input": "2 2 3\n1 2 2\n2 1 3\n2 1\n2 2\n2 3", "output": "2" }, { "input": "5 4 3\n1 2 999999999\n2 3 1000000000\n3 4 529529529\n5 1 524524524\n5 524444444\n5 529999999\n2 1000000000", "output": ...
77
2,764,800
-1
1,001
928
Login Verification
[ "*special", "strings" ]
null
null
When registering in a social network, users are allowed to create their own convenient login to make it easier to share contacts, print it on business cards, etc. Login is an arbitrary sequence of lower and uppercase latin letters, digits and underline symbols (Β«_Β»). However, in order to decrease the number of frauds and user-inattention related issues, it is prohibited to register a login if it is similar with an already existing login. More precisely, two logins *s* and *t* are considered similar if we can transform *s* to *t* via a sequence of operations of the following types: - transform lowercase letters to uppercase and vice versa; - change letter Β«OΒ» (uppercase latin letter) to digit Β«0Β» and vice versa; - change digit Β«1Β» (one) to any letter among Β«lΒ» (lowercase latin Β«LΒ»), Β«IΒ» (uppercase latin Β«iΒ») and vice versa, or change one of these letters to other. For example, logins Β«CodeforcesΒ» and Β«codef0rcesΒ» as well as Β«OO0OOO00O0OOO0O00OOO0OO_lolΒ» and Β«OO0OOO0O00OOO0O00OO0OOO_1oIΒ» are considered similar whereas Β«CodeforcesΒ» and Β«Code_forcesΒ» are not. You're given a list of existing logins with no two similar amonst and a newly created user login. Check whether this new login is similar with any of the existing ones.
The first line contains a non-empty string *s* consisting of lower and uppercase latin letters, digits and underline symbols (Β«_Β») with length not exceeding 50 Β β€” the login itself. The second line contains a single integer *n* (1<=≀<=*n*<=≀<=1<=000)Β β€” the number of existing logins. The next *n* lines describe the existing logins, following the same constraints as the user login (refer to the first line of the input). It's guaranteed that no two existing logins are similar.
Print Β«YesΒ» (without quotes), if user can register via this login, i.e. none of the existing logins is similar with it. Otherwise print Β«NoΒ» (without quotes).
[ "1_wat\n2\n2_wat\nwat_1\n", "000\n3\n00\nooA\noOo\n", "_i_\n3\n__i_\n_1_\nI\n", "La0\n3\n2a0\nLa1\n1a0\n", "abc\n1\naBc\n", "0Lil\n2\nLIL0\n0Ril\n" ]
[ "Yes\n", "No\n", "No\n", "No\n", "No\n", "Yes\n" ]
In the second sample case the user wants to create a login consisting of three zeros. It's impossible due to collision with the third among the existing. In the third sample case the new login is similar with the second one.
[ { "input": "1_wat\n2\n2_wat\nwat_1", "output": "Yes" }, { "input": "000\n3\n00\nooA\noOo", "output": "No" }, { "input": "_i_\n3\n__i_\n_1_\nI", "output": "No" }, { "input": "La0\n3\n2a0\nLa1\n1a0", "output": "No" }, { "input": "abc\n1\naBc", "output": "No" }...
93
5,632,000
3
1,003
34
Page Numbers
[ "expression parsing", "implementation", "sortings", "strings" ]
C. Page Numbers
2
256
Β«BersoftΒ» company is working on a new version of its most popular text editor β€” Bord 2010. Bord, like many other text editors, should be able to print out multipage documents. A user keys a sequence of the document page numbers that he wants to print out (separates them with a comma, without spaces). Your task is to write a part of the program, responsible for Β«standardizationΒ» of this sequence. Your program gets the sequence, keyed by the user, as input. The program should output this sequence in format *l*1-*r*1,*l*2-*r*2,...,*l**k*-*r**k*, where *r**i*<=+<=1<=&lt;<=*l**i*<=+<=1 for all *i* from 1 to *k*<=-<=1, and *l**i*<=≀<=*r**i*. The new sequence should contain all the page numbers, keyed by the user, and nothing else. If some page number appears in the input sequence several times, its appearances, starting from the second one, should be ignored. If for some element *i* from the new sequence *l**i*<==<=*r**i*, this element should be output as *l**i*, and not as Β«*l**i*<=-<=*l**i*Β». For example, sequence 1,2,3,1,1,2,6,6,2 should be output as 1-3,6.
The only line contains the sequence, keyed by the user. The sequence contains at least one and at most 100 positive integer numbers. It's guaranteed, that this sequence consists of positive integer numbers, not exceeding 1000, separated with a comma, doesn't contain any other characters, apart from digits and commas, can't end with a comma, and the numbers don't contain leading zeroes. Also it doesn't start with a comma or contain more than one comma in a row.
Output the sequence in the required format.
[ "1,2,3,1,1,2,6,6,2\n", "3,2,1\n", "30,20,10\n" ]
[ "1-3,6\n", "1-3\n", "10,20,30\n" ]
none
[ { "input": "1,2,3,1,1,2,6,6,2", "output": "1-3,6" }, { "input": "3,2,1", "output": "1-3" }, { "input": "30,20,10", "output": "10,20,30" }, { "input": "826,747,849,687,437", "output": "437,687,747,826,849" }, { "input": "999,999,993,969,999", "output": "969,993...
92
0
3.977
1,004
766
Mahmoud and Longest Uncommon Subsequence
[ "constructive algorithms", "strings" ]
null
null
While Mahmoud and Ehab were practicing for IOI, they found a problem which name was Longest common subsequence. They solved it, and then Ehab challenged Mahmoud with another problem. Given two strings *a* and *b*, find the length of their longest uncommon subsequence, which is the longest string that is a subsequence of one of them and not a subsequence of the other. A subsequence of some string is a sequence of characters that appears in the same order in the string, The appearances don't have to be consecutive, for example, strings "ac", "bc", "abc" and "a" are subsequences of string "abc" while strings "abbc" and "acb" are not. The empty string is a subsequence of any string. Any string is a subsequence of itself.
The first line contains string *a*, and the second lineΒ β€” string *b*. Both of these strings are non-empty and consist of lowercase letters of English alphabet. The length of each string is not bigger than 105 characters.
If there's no uncommon subsequence, print "-1". Otherwise print the length of the longest uncommon subsequence of *a* and *b*.
[ "abcd\ndefgh\n", "a\na\n" ]
[ "5\n", "-1\n" ]
In the first example: you can choose "defgh" from string *b* as it is the longest subsequence of string *b* that doesn't appear as a subsequence of string *a*.
[ { "input": "abcd\ndefgh", "output": "5" }, { "input": "a\na", "output": "-1" }, { "input": "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaacccccccccccccccccccccccccccccccccccccccccccccccccc\naaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaadddddddddddddddddddddddddddddddddddddddddddd...
46
4,608,000
3
1,007
978
File Name
[ "greedy", "strings" ]
null
null
You can not just take the file and send it. When Polycarp trying to send a file in the social network "Codehorses", he encountered an unexpected problem. If the name of the file contains three or more "x" (lowercase Latin letters "x") in a row, the system considers that the file content does not correspond to the social network topic. In this case, the file is not sent and an error message is displayed. Determine the minimum number of characters to remove from the file name so after that the name does not contain "xxx" as a substring. Print 0 if the file name does not initially contain a forbidden substring "xxx". You can delete characters in arbitrary positions (not necessarily consecutive). If you delete a character, then the length of a string is reduced by $1$. For example, if you delete the character in the position $2$ from the string "exxxii", then the resulting string is "exxii".
The first line contains integer $n$ $(3 \le n \le 100)$ β€” the length of the file name. The second line contains a string of length $n$ consisting of lowercase Latin letters only β€” the file name.
Print the minimum number of characters to remove from the file name so after that the name does not contain "xxx" as a substring. If initially the file name dost not contain a forbidden substring "xxx", print 0.
[ "6\nxxxiii\n", "5\nxxoxx\n", "10\nxxxxxxxxxx\n" ]
[ "1\n", "0\n", "8\n" ]
In the first example Polycarp tried to send a file with name contains number $33$, written in Roman numerals. But he can not just send the file, because it name contains three letters "x" in a row. To send the file he needs to remove any one of this letters.
[ { "input": "6\nxxxiii", "output": "1" }, { "input": "5\nxxoxx", "output": "0" }, { "input": "10\nxxxxxxxxxx", "output": "8" }, { "input": "100\nxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", "output": "98" }, { ...
46
0
0
1,009
610
Pasha and Stick
[ "combinatorics", "math" ]
null
null
Pasha has a wooden stick of some positive integer length *n*. He wants to perform exactly three cuts to get four parts of the stick. Each part must have some positive integer length and the sum of these lengths will obviously be *n*. Pasha likes rectangles but hates squares, so he wonders, how many ways are there to split a stick into four parts so that it's possible to form a rectangle using these parts, but is impossible to form a square. Your task is to help Pasha and count the number of such ways. Two ways to cut the stick are considered distinct if there exists some integer *x*, such that the number of parts of length *x* in the first way differ from the number of parts of length *x* in the second way.
The first line of the input contains a positive integer *n* (1<=≀<=*n*<=≀<=2Β·109) β€” the length of Pasha's stick.
The output should contain a single integerΒ β€” the number of ways to split Pasha's stick into four parts of positive integer length so that it's possible to make a rectangle by connecting the ends of these parts, but is impossible to form a square.
[ "6\n", "20\n" ]
[ "1\n", "4\n" ]
There is only one way to divide the stick in the first sample {1, 1, 2, 2}. Four ways to divide the stick in the second sample are {1, 1, 9, 9}, {2, 2, 8, 8}, {3, 3, 7, 7} and {4, 4, 6, 6}. Note that {5, 5, 5, 5} doesn't work.
[ { "input": "6", "output": "1" }, { "input": "20", "output": "4" }, { "input": "1", "output": "0" }, { "input": "2", "output": "0" }, { "input": "3", "output": "0" }, { "input": "4", "output": "0" }, { "input": "2000000000", "output": "4...
93
0
0
1,011
2
The least round way
[ "dp", "math" ]
B. The least round way
2
64
There is a square matrix *n*<=Γ—<=*n*, consisting of non-negative integer numbers. You should find such a way on it that - starts in the upper left cell of the matrix; - each following cell is to the right or down from the current cell; - the way ends in the bottom right cell. Moreover, if we multiply together all the numbers along the way, the result should be the least "round". In other words, it should end in the least possible number of zeros.
The first line contains an integer number *n* (2<=≀<=*n*<=≀<=1000), *n* is the size of the matrix. Then follow *n* lines containing the matrix elements (non-negative integer numbers not exceeding 109).
In the first line print the least number of trailing zeros. In the second line print the correspondent way itself.
[ "3\n1 2 3\n4 5 6\n7 8 9\n" ]
[ "0\nDDRR\n" ]
none
[ { "input": "3\n1 2 3\n4 5 6\n7 8 9", "output": "0\nDDRR" }, { "input": "2\n7 6\n3 8", "output": "0\nDR" }, { "input": "3\n4 10 5\n10 9 4\n6 5 3", "output": "1\nDRRD" }, { "input": "4\n1 1 9 9\n3 4 7 3\n7 9 1 7\n1 7 1 5", "output": "0\nDDDRRR" }, { "input": "5\n8 3...
155
3,891,200
0
1,012
611
New Year and Domino
[ "dp", "implementation" ]
null
null
They say "years are like dominoes, tumbling one after the other". But would a year fit into a grid? I don't think so. Limak is a little polar bear who loves to play. He has recently got a rectangular grid with *h* rows and *w* columns. Each cell is a square, either empty (denoted by '.') or forbidden (denoted by '#'). Rows are numbered 1 through *h* from top to bottom. Columns are numbered 1 through *w* from left to right. Also, Limak has a single domino. He wants to put it somewhere in a grid. A domino will occupy exactly two adjacent cells, located either in one row or in one column. Both adjacent cells must be empty and must be inside a grid. Limak needs more fun and thus he is going to consider some queries. In each query he chooses some rectangle and wonders, how many way are there to put a single domino inside of the chosen rectangle?
The first line of the input contains two integers *h* and *w* (1<=≀<=*h*,<=*w*<=≀<=500) – the number of rows and the number of columns, respectively. The next *h* lines describe a grid. Each line contains a string of the length *w*. Each character is either '.' or '#'Β β€” denoting an empty or forbidden cell, respectively. The next line contains a single integer *q* (1<=≀<=*q*<=≀<=100<=000)Β β€” the number of queries. Each of the next *q* lines contains four integers *r*1*i*, *c*1*i*, *r*2*i*, *c*2*i* (1<=≀<=*r*1*i*<=≀<=*r*2*i*<=≀<=*h*,<=1<=≀<=*c*1*i*<=≀<=*c*2*i*<=≀<=*w*)Β β€” the *i*-th query. Numbers *r*1*i* and *c*1*i* denote the row and the column (respectively) of the upper left cell of the rectangle. Numbers *r*2*i* and *c*2*i* denote the row and the column (respectively) of the bottom right cell of the rectangle.
Print *q* integers, *i*-th should be equal to the number of ways to put a single domino inside the *i*-th rectangle.
[ "5 8\n....#..#\n.#......\n##.#....\n##..#.##\n........\n4\n1 1 2 3\n4 1 4 1\n1 2 4 5\n2 5 5 8\n", "7 39\n.......................................\n.###..###..#..###.....###..###..#..###.\n...#..#.#..#..#.........#..#.#..#..#...\n.###..#.#..#..###.....###..#.#..#..###.\n.#....#.#..#....#.....#....#.#..#..#.#.\n.###...
[ "4\n0\n10\n15\n", "53\n89\n120\n23\n0\n2\n" ]
A red frame below corresponds to the first query of the first sample. A domino can be placed in 4 possible ways.
[ { "input": "5 8\n....#..#\n.#......\n##.#....\n##..#.##\n........\n4\n1 1 2 3\n4 1 4 1\n1 2 4 5\n2 5 5 8", "output": "4\n0\n10\n15" }, { "input": "7 39\n.......................................\n.###..###..#..###.....###..###..#..###.\n...#..#.#..#..#.........#..#.#..#..#...\n.###..#.#..#..###.....##...
2,371
13,516,800
3
1,013
400
Inna and New Matrix of Candies
[ "brute force", "implementation", "schedules" ]
null
null
Inna likes sweets and a game called the "Candy Matrix". Today, she came up with the new game "Candy Matrix 2: Reload". The field for the new game is a rectangle table of size *n*<=Γ—<=*m*. Each line of the table contains one cell with a dwarf figurine, one cell with a candy, the other cells of the line are empty. The game lasts for several moves. During each move the player should choose all lines of the matrix where dwarf is not on the cell with candy and shout "Let's go!". After that, all the dwarves from the chosen lines start to simultaneously move to the right. During each second, each dwarf goes to the adjacent cell that is located to the right of its current cell. The movement continues until one of the following events occurs: - some dwarf in one of the chosen lines is located in the rightmost cell of his row; - some dwarf in the chosen lines is located in the cell with the candy. The point of the game is to transport all the dwarves to the candy cells. Inna is fabulous, as she came up with such an interesting game. But what about you? Your task is to play this game optimally well. Specifically, you should say by the given game field what minimum number of moves the player needs to reach the goal of the game.
The first line of the input contains two integers *n* and *m* (1<=≀<=*n*<=≀<=1000;Β 2<=≀<=*m*<=≀<=1000). Next *n* lines each contain *m* characters β€” the game field for the "Candy Martix 2: Reload". Character "*" represents an empty cell of the field, character "G" represents a dwarf and character "S" represents a candy. The matrix doesn't contain other characters. It is guaranteed that each line contains exactly one character "G" and one character "S".
In a single line print a single integer β€” either the minimum number of moves needed to achieve the aim of the game, or -1, if the aim cannot be achieved on the given game field.
[ "3 4\n*G*S\nG**S\n*G*S\n", "1 3\nS*G\n" ]
[ "2\n", "-1\n" ]
none
[ { "input": "3 4\n*G*S\nG**S\n*G*S", "output": "2" }, { "input": "1 3\nS*G", "output": "-1" }, { "input": "10 10\nG********S\n*G*******S\n**G******S\n***G*****S\n****G****S\n*****G***S\n******G**S\n*******G*S\n********GS\nG********S", "output": "9" }, { "input": "5 10\nG***S**...
62
0
0
1,016
656
You're a Professional
[ "*special" ]
null
null
A simple recommendation system would recommend a user things liked by a certain number of their friends. In this problem you will implement part of such a system. You are given user's friends' opinions about a list of items. You are also given a threshold *T* β€” the minimal number of "likes" necessary for an item to be recommended to the user. Output the number of items in the list liked by at least *T* of user's friends.
The first line of the input will contain three space-separated integers: the number of friends *F* (1<=≀<=*F*<=≀<=10), the number of items *I* (1<=≀<=*I*<=≀<=10) and the threshold *T* (1<=≀<=*T*<=≀<=*F*). The following *F* lines of input contain user's friends' opinions. *j*-th character of *i*-th line is 'Y' if *i*-th friend likes *j*-th item, and 'N' otherwise.
Output an integer β€” the number of items liked by at least *T* of user's friends.
[ "3 3 2\nYYY\nNNN\nYNY\n", "4 4 1\nNNNY\nNNYN\nNYNN\nYNNN\n" ]
[ "2\n", "4\n" ]
none
[ { "input": "3 3 2\nYYY\nNNN\nYNY", "output": "2" }, { "input": "4 4 1\nNNNY\nNNYN\nNYNN\nYNNN", "output": "4" }, { "input": "3 5 2\nNYNNY\nYNNNN\nNNYYN", "output": "0" }, { "input": "1 10 1\nYYYNYNNYNN", "output": "5" }, { "input": "10 1 5\nY\nN\nN\nN\nY\nN\nN\nY\...
46
5,529,600
0
1,017
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)Β β€” 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)Β β€” the speeds of magical impulses for Harry Potter and He-Who-Must-Not-Be-Named, respectively.
Print a single real numberΒ β€” 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...
77
0
3
1,018
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) β€” 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*|<=≀<=2Β·104) β€” 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...
124
5,632,000
3.95851
1,020
891
Pride
[ "brute force", "dp", "greedy", "math", "number theory" ]
null
null
You have an array *a* with length *n*, you can perform operations. Each operation is like this: choose two adjacent elements from *a*, say *x* and *y*, and replace one of them with *gcd*(*x*,<=*y*), where *gcd* denotes the [greatest common divisor](https://en.wikipedia.org/wiki/Greatest_common_divisor). What is the minimum number of operations you need to make all of the elements equal to 1?
The first line of the input contains one integer *n* (1<=≀<=*n*<=≀<=2000) β€” the number of elements in the array. The second line contains *n* space separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≀<=*a**i*<=≀<=109)Β β€” the elements of the array.
Print -1, if it is impossible to turn all numbers to 1. Otherwise, print the minimum number of operations needed to make all numbers equal to 1.
[ "5\n2 2 3 4 6\n", "4\n2 4 6 8\n", "3\n2 6 9\n" ]
[ "5\n", "-1\n", "4\n" ]
In the first sample you can turn all numbers to 1 using the following 5 moves: - [2, 2, 3, 4, 6]. - [2, 1, 3, 4, 6] - [2, 1, 3, 1, 6] - [2, 1, 1, 1, 6] - [1, 1, 1, 1, 6] - [1, 1, 1, 1, 1] We can prove that in this case it is not possible to make all numbers one using less than 5 moves.
[ { "input": "5\n2 2 3 4 6", "output": "5" }, { "input": "4\n2 4 6 8", "output": "-1" }, { "input": "3\n2 6 9", "output": "4" }, { "input": "15\n10 10 10 10 10 10 21 21 21 21 21 21 21 21 21", "output": "15" }, { "input": "12\n10 10 14 14 14 14 14 14 14 14 21 21", ...
202
2,560,000
0
1,021
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)Β β€” 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...
888
11,468,800
3
1,022
853
Jury Meeting
[ "greedy", "sortings", "two pointers" ]
null
null
Country of Metropolia is holding Olympiad of Metrpolises soon. It mean that all jury members of the olympiad should meet together in Metropolis (the capital of the country) for the problem preparation process. There are *n*<=+<=1 cities consecutively numbered from 0 to *n*. City 0 is Metropolis that is the meeting point for all jury members. For each city from 1 to *n* there is exactly one jury member living there. Olympiad preparation is a long and demanding process that requires *k* days of work. For all of these *k* days each of the *n* jury members should be present in Metropolis to be able to work on problems. You know the flight schedule in the country (jury members consider themselves important enough to only use flights for transportation). All flights in Metropolia are either going to Metropolis or out of Metropolis. There are no night flights in Metropolia, or in the other words, plane always takes off at the same day it arrives. On his arrival day and departure day jury member is not able to discuss the olympiad. All flights in Megapolia depart and arrive at the same day. Gather everybody for *k* days in the capital is a hard objective, doing that while spending the minimum possible money is even harder. Nevertheless, your task is to arrange the cheapest way to bring all of the jury members to Metrpolis, so that they can work together for *k* days and then send them back to their home cities. Cost of the arrangement is defined as a total cost of tickets for all used flights. It is allowed for jury member to stay in Metropolis for more than *k* days.
The first line of input contains three integers *n*, *m* and *k* (1<=≀<=*n*<=≀<=105, 0<=≀<=*m*<=≀<=105, 1<=≀<=*k*<=≀<=106). The *i*-th of the following *m* lines contains the description of the *i*-th flight defined by four integers *d**i*, *f**i*, *t**i* and *c**i* (1<=≀<=*d**i*<=≀<=106, 0<=≀<=*f**i*<=≀<=*n*, 0<=≀<=*t**i*<=≀<=*n*, 1<=≀<=*c**i*<=≀<=106, exactly one of *f**i* and *t**i* equals zero), the day of departure (and arrival), the departure city, the arrival city and the ticket cost.
Output the only integer that is the minimum cost of gathering all jury members in city 0 for *k* days and then sending them back to their home cities. If it is impossible to gather everybody in Metropolis for *k* days and then send them back to their home cities, output "-1" (without the quotes).
[ "2 6 5\n1 1 0 5000\n3 2 0 5500\n2 2 0 6000\n15 0 2 9000\n9 0 1 7000\n8 0 2 6500\n", "2 4 5\n1 2 0 5000\n2 1 0 4500\n2 1 0 3000\n8 0 1 6000\n" ]
[ "24500\n", "-1\n" ]
The optimal way to gather everybody in Metropolis in the first sample test is to use flights that take place on days 1, 2, 8 and 9. The only alternative option is to send jury member from second city back home on day 15, that would cost 2500 more. In the second sample it is impossible to send jury member from city 2 back home from Metropolis.
[ { "input": "2 6 5\n1 1 0 5000\n3 2 0 5500\n2 2 0 6000\n15 0 2 9000\n9 0 1 7000\n8 0 2 6500", "output": "24500" }, { "input": "2 4 5\n1 2 0 5000\n2 1 0 4500\n2 1 0 3000\n8 0 1 6000", "output": "-1" }, { "input": "2 5 5\n1 1 0 1\n2 2 0 100\n3 2 0 10\n9 0 1 1000\n10 0 2 10000", "output"...
389
19,251,200
3
1,024
762
k-th divisor
[ "math", "number theory" ]
null
null
You are given two integers *n* and *k*. Find *k*-th smallest divisor of *n*, or report that it doesn't exist. Divisor of *n* is any such natural number, that *n* can be divided by it without remainder.
The first line contains two integers *n* and *k* (1<=≀<=*n*<=≀<=1015, 1<=≀<=*k*<=≀<=109).
If *n* has less than *k* divisors, output -1. Otherwise, output the *k*-th smallest divisor of *n*.
[ "4 2\n", "5 3\n", "12 5\n" ]
[ "2\n", "-1\n", "6\n" ]
In the first example, number 4 has three divisors: 1, 2 and 4. The second one is 2. In the second example, number 5 has only two divisors: 1 and 5. The third divisor doesn't exist, so the answer is -1.
[ { "input": "4 2", "output": "2" }, { "input": "5 3", "output": "-1" }, { "input": "12 5", "output": "6" }, { "input": "1 1", "output": "1" }, { "input": "866421317361600 26880", "output": "866421317361600" }, { "input": "866421317361600 26881", "ou...
748
23,552,000
3
1,027
597
Restaurant
[ "dp", "greedy", "sortings" ]
null
null
A restaurant received *n* orders for the rental. Each rental order reserve the restaurant for a continuous period of time, the *i*-th order is characterized by two time values β€” the start time *l**i* and the finish time *r**i* (*l**i*<=≀<=*r**i*). Restaurant management can accept and reject orders. What is the maximal number of orders the restaurant can accept? No two accepted orders can intersect, i.e. they can't share even a moment of time. If one order ends in the moment other starts, they can't be accepted both.
The first line contains integer number *n* (1<=≀<=*n*<=≀<=5Β·105) β€” number of orders. The following *n* lines contain integer values *l**i* and *r**i* each (1<=≀<=*l**i*<=≀<=*r**i*<=≀<=109).
Print the maximal number of orders that can be accepted.
[ "2\n7 11\n4 7\n", "5\n1 2\n2 3\n3 4\n4 5\n5 6\n", "6\n4 8\n1 5\n4 7\n2 5\n1 3\n6 8\n" ]
[ "1\n", "3\n", "2\n" ]
none
[ { "input": "2\n7 11\n4 7", "output": "1" }, { "input": "5\n1 2\n2 3\n3 4\n4 5\n5 6", "output": "3" }, { "input": "6\n4 8\n1 5\n4 7\n2 5\n1 3\n6 8", "output": "2" }, { "input": "1\n1 1", "output": "1" }, { "input": "2\n4 6\n4 8", "output": "1" }, { "inp...
31
102,400
0
1,028
220
Little Elephant and Problem
[ "implementation", "sortings" ]
null
null
The Little Elephant has got a problem β€” somebody has been touching his sorted by non-decreasing array *a* of length *n* and possibly swapped some elements of the array. The Little Elephant doesn't want to call the police until he understands if he could have accidentally changed the array himself. He thinks that he could have accidentally changed array *a*, only if array *a* can be sorted in no more than one operation of swapping elements (not necessarily adjacent). That is, the Little Elephant could have accidentally swapped some two elements. Help the Little Elephant, determine if he could have accidentally changed the array *a*, sorted by non-decreasing, himself.
The first line contains a single integer *n* (2<=≀<=*n*<=≀<=105) β€” the size of array *a*. The next line contains *n* positive integers, separated by single spaces and not exceeding 109, β€” array *a*. Note that the elements of the array are not necessarily distinct numbers.
In a single line print "YES" (without the quotes) if the Little Elephant could have accidentally changed the array himself, and "NO" (without the quotes) otherwise.
[ "2\n1 2\n", "3\n3 2 1\n", "4\n4 3 2 1\n" ]
[ "YES\n", "YES\n", "NO\n" ]
In the first sample the array has already been sorted, so to sort it, we need 0 swap operations, that is not more than 1. Thus, the answer is "YES". In the second sample we can sort the array if we swap elements 1 and 3, so we need 1 swap operation to sort the array. Thus, the answer is "YES". In the third sample we can't sort the array in more than one swap operation, so the answer is "NO".
[ { "input": "2\n1 2", "output": "YES" }, { "input": "3\n3 2 1", "output": "YES" }, { "input": "4\n4 3 2 1", "output": "NO" }, { "input": "3\n1 3 2", "output": "YES" }, { "input": "2\n2 1", "output": "YES" }, { "input": "9\n7 7 8 8 10 10 10 10 1000000000...
264
9,113,600
3
1,029
198
About Bacteria
[ "implementation", "math" ]
null
null
Qwerty the Ranger took up a government job and arrived on planet Mars. He should stay in the secret lab and conduct some experiments on bacteria that have funny and abnormal properties. The job isn't difficult, but the salary is high. At the beginning of the first experiment there is a single bacterium in the test tube. Every second each bacterium in the test tube divides itself into *k* bacteria. After that some abnormal effects create *b* more bacteria in the test tube. Thus, if at the beginning of some second the test tube had *x* bacteria, then at the end of the second it will have *kx*<=+<=*b* bacteria. The experiment showed that after *n* seconds there were exactly *z* bacteria and the experiment ended at this point. For the second experiment Qwerty is going to sterilize the test tube and put there *t* bacteria. He hasn't started the experiment yet but he already wonders, how many seconds he will need to grow at least *z* bacteria. The ranger thinks that the bacteria will divide by the same rule as in the first experiment. Help Qwerty and find the minimum number of seconds needed to get a tube with at least *z* bacteria in the second experiment.
The first line contains four space-separated integers *k*, *b*, *n* and *t* (1<=≀<=*k*,<=*b*,<=*n*,<=*t*<=≀<=106) β€” the parameters of bacterial growth, the time Qwerty needed to grow *z* bacteria in the first experiment and the initial number of bacteria in the second experiment, correspondingly.
Print a single number β€” the minimum number of seconds Qwerty needs to grow at least *z* bacteria in the tube.
[ "3 1 3 5\n", "1 4 4 7\n", "2 2 4 100\n" ]
[ "2", "3", "0" ]
none
[ { "input": "3 1 3 5", "output": "2" }, { "input": "1 4 4 7", "output": "3" }, { "input": "2 2 4 100", "output": "0" }, { "input": "1 2 3 100", "output": "0" }, { "input": "10 10 10 123456", "output": "6" }, { "input": "847 374 283 485756", "output"...
218
20,172,800
0
1,031
486
Calculating Function
[ "implementation", "math" ]
null
null
For a positive integer *n* let's define a function *f*: *f*(*n*)<==<=<=-<=1<=+<=2<=-<=3<=+<=..<=+<=(<=-<=1)*n**n* Your task is to calculate *f*(*n*) for a given integer *n*.
The single line contains the positive integer *n* (1<=≀<=*n*<=≀<=1015).
Print *f*(*n*) in a single line.
[ "4\n", "5\n" ]
[ "2\n", "-3\n" ]
*f*(4) =  - 1 + 2 - 3 + 4 = 2 *f*(5) =  - 1 + 2 - 3 + 4 - 5 =  - 3
[ { "input": "4", "output": "2" }, { "input": "5", "output": "-3" }, { "input": "1000000000", "output": "500000000" }, { "input": "1000000001", "output": "-500000001" }, { "input": "1000000000000000", "output": "500000000000000" }, { "input": "100", ...
46
0
3
1,032
950
Intercepted Message
[ "greedy", "implementation" ]
null
null
Hacker Zhorik wants to decipher two secret messages he intercepted yesterday. Yeah message is a sequence of encrypted blocks, each of them consists of several bytes of information. Zhorik knows that each of the messages is an archive containing one or more files. Zhorik knows how each of these archives was transferred through the network: if an archive consists of *k* files of sizes *l*1,<=*l*2,<=...,<=*l**k* bytes, then the *i*-th file is split to one or more blocks *b**i*,<=1,<=*b**i*,<=2,<=...,<=*b**i*,<=*m**i* (here the total length of the blocks *b**i*,<=1<=+<=*b**i*,<=2<=+<=...<=+<=*b**i*,<=*m**i* is equal to the length of the file *l**i*), and after that all blocks are transferred through the network, maintaining the order of files in the archive. Zhorik thinks that the two messages contain the same archive, because their total lengths are equal. However, each file can be split in blocks in different ways in the two messages. You are given the lengths of blocks in each of the two messages. Help Zhorik to determine what is the maximum number of files could be in the archive, if the Zhorik's assumption is correct.
The first line contains two integers *n*, *m* (1<=≀<=*n*,<=*m*<=≀<=105) β€” the number of blocks in the first and in the second messages. The second line contains *n* integers *x*1,<=*x*2,<=...,<=*x**n* (1<=≀<=*x**i*<=≀<=106) β€” the length of the blocks that form the first message. The third line contains *m* integers *y*1,<=*y*2,<=...,<=*y**m* (1<=≀<=*y**i*<=≀<=106) β€” the length of the blocks that form the second message. It is guaranteed that *x*1<=+<=...<=+<=*x**n*<==<=*y*1<=+<=...<=+<=*y**m*. Also, it is guaranteed that *x*1<=+<=...<=+<=*x**n*<=≀<=106.
Print the maximum number of files the intercepted array could consist of.
[ "7 6\n2 5 3 1 11 4 4\n7 8 2 4 1 8\n", "3 3\n1 10 100\n1 100 10\n", "1 4\n4\n1 1 1 1\n" ]
[ "3\n", "2\n", "1\n" ]
In the first example the maximum number of files in the archive is 3. For example, it is possible that in the archive are three files of sizes 2 + 5 = 7, 15 = 3 + 1 + 11 = 8 + 2 + 4 + 1 and 4 + 4 = 8. In the second example it is possible that the archive contains two files of sizes 1 and 110 = 10 + 100 = 100 + 10. Note that the order of files is kept while transferring archives through the network, so we can't say that there are three files of sizes 1, 10 and 100. In the third example the only possibility is that the archive contains a single file of size 4.
[ { "input": "7 6\n2 5 3 1 11 4 4\n7 8 2 4 1 8", "output": "3" }, { "input": "3 3\n1 10 100\n1 100 10", "output": "2" }, { "input": "1 4\n4\n1 1 1 1", "output": "1" }, { "input": "1 1\n1000000\n1000000", "output": "1" }, { "input": "3 5\n2 2 9\n2 1 4 2 4", "outp...
1,000
2,560,000
0
1,034
807
Is it rated?
[ "implementation", "sortings" ]
null
null
Is it rated? Here it is. The Ultimate Question of Competitive Programming, Codeforces, and Everything. And you are here to answer it. Another Codeforces round has been conducted. No two participants have the same number of points. For each participant, from the top to the bottom of the standings, their rating before and after the round is known. It's known that if at least one participant's rating has changed, then the round was rated for sure. It's also known that if the round was rated and a participant with lower rating took a better place in the standings than a participant with higher rating, then at least one round participant's rating has changed. In this problem, you should not make any other assumptions about the rating system. Determine if the current round is rated, unrated, or it's impossible to determine whether it is rated of not.
The first line contains a single integer *n* (2<=≀<=*n*<=≀<=1000)Β β€” the number of round participants. Each of the next *n* lines contains two integers *a**i* and *b**i* (1<=≀<=*a**i*,<=*b**i*<=≀<=4126)Β β€” the rating of the *i*-th participant before and after the round, respectively. The participants are listed in order from the top to the bottom of the standings.
If the round is rated for sure, print "rated". If the round is unrated for sure, print "unrated". If it's impossible to determine whether the round is rated or not, print "maybe".
[ "6\n3060 3060\n2194 2194\n2876 2903\n2624 2624\n3007 2991\n2884 2884\n", "4\n1500 1500\n1300 1300\n1200 1200\n1400 1400\n", "5\n3123 3123\n2777 2777\n2246 2246\n2246 2246\n1699 1699\n" ]
[ "rated\n", "unrated\n", "maybe\n" ]
In the first example, the ratings of the participants in the third and fifth places have changed, therefore, the round was rated. In the second example, no one's rating has changed, but the participant in the second place has lower rating than the participant in the fourth place. Therefore, if the round was rated, someone's rating would've changed for sure. In the third example, no one's rating has changed, and the participants took places in non-increasing order of their rating. Therefore, it's impossible to determine whether the round is rated or not.
[ { "input": "6\n3060 3060\n2194 2194\n2876 2903\n2624 2624\n3007 2991\n2884 2884", "output": "rated" }, { "input": "4\n1500 1500\n1300 1300\n1200 1200\n1400 1400", "output": "unrated" }, { "input": "5\n3123 3123\n2777 2777\n2246 2246\n2246 2246\n1699 1699", "output": "maybe" }, { ...
62
0
0
1,035
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) β€” 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) β€” the date of the exam in the schedule and the early date of passing the *i*-th exam, correspondingly.
Print a single integer β€” 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": "...
46
716,800
0
1,037
340
The Wall
[ "math" ]
null
null
Iahub and his friend Floyd have started painting a wall. Iahub is painting the wall red and Floyd is painting it pink. You can consider the wall being made of a very large number of bricks, numbered 1, 2, 3 and so on. Iahub has the following scheme of painting: he skips *x*<=-<=1 consecutive bricks, then he paints the *x*-th one. That is, he'll paint bricks *x*, 2Β·*x*, 3Β·*x* and so on red. Similarly, Floyd skips *y*<=-<=1 consecutive bricks, then he paints the *y*-th one. Hence he'll paint bricks *y*, 2Β·*y*, 3Β·*y* and so on pink. After painting the wall all day, the boys observed that some bricks are painted both red and pink. Iahub has a lucky number *a* and Floyd has a lucky number *b*. Boys wonder how many bricks numbered no less than *a* and no greater than *b* are painted both red and pink. This is exactly your task: compute and print the answer to the question.
The input will have a single line containing four integers in this order: *x*, *y*, *a*, *b*. (1<=≀<=*x*,<=*y*<=≀<=1000, 1<=≀<=*a*,<=*b*<=≀<=2Β·109, *a*<=≀<=*b*).
Output a single integer β€” the number of bricks numbered no less than *a* and no greater than *b* that are painted both red and pink.
[ "2 3 6 18\n" ]
[ "3" ]
Let's look at the bricks from *a* to *b* (*a* = 6, *b* = 18). The bricks colored in red are numbered 6, 8, 10, 12, 14, 16, 18. The bricks colored in pink are numbered 6, 9, 12, 15, 18. The bricks colored in both red and pink are numbered with 6, 12 and 18.
[ { "input": "2 3 6 18", "output": "3" }, { "input": "4 6 20 201", "output": "15" }, { "input": "15 27 100 10000", "output": "74" }, { "input": "105 60 3456 78910", "output": "179" }, { "input": "1 1 1000 100000", "output": "99001" }, { "input": "3 2 5 5...
218
5,120,000
-1
1,041
1,004
Sonya and Hotels
[ "implementation" ]
null
null
Sonya decided that having her own hotel business is the best way of earning money because she can profit and rest wherever she wants. The country where Sonya lives is an endless line. There is a city in each integer coordinate on this line. She has $n$ hotels, where the $i$-th hotel is located in the city with coordinate $x_i$. Sonya is a smart girl, so she does not open two or more hotels in the same city. Sonya understands that her business needs to be expanded by opening new hotels, so she decides to build one more. She wants to make the minimum distance from this hotel to all others to be equal to $d$. The girl understands that there are many possible locations to construct such a hotel. Thus she wants to know the number of possible coordinates of the cities where she can build a new hotel. Because Sonya is lounging in a jacuzzi in one of her hotels, she is asking you to find the number of cities where she can build a new hotel so that the minimum distance from the original $n$ hotels to the new one is equal to $d$.
The first line contains two integers $n$ and $d$ ($1\leq n\leq 100$, $1\leq d\leq 10^9$)Β β€” the number of Sonya's hotels and the needed minimum distance from a new hotel to all others. The second line contains $n$ different integers in strictly increasing order $x_1, x_2, \ldots, x_n$ ($-10^9\leq x_i\leq 10^9$)Β β€” coordinates of Sonya's hotels.
Print the number of cities where Sonya can build a new hotel so that the minimum distance from this hotel to all others is equal to $d$.
[ "4 3\n-3 2 9 16\n", "5 2\n4 8 11 18 19\n" ]
[ "6\n", "5\n" ]
In the first example, there are $6$ possible cities where Sonya can build a hotel. These cities have coordinates $-6$, $5$, $6$, $12$, $13$, and $19$. In the second example, there are $5$ possible cities where Sonya can build a hotel. These cities have coordinates $2$, $6$, $13$, $16$, and $21$.
[ { "input": "4 3\n-3 2 9 16", "output": "6" }, { "input": "5 2\n4 8 11 18 19", "output": "5" }, { "input": "10 10\n-67 -59 -49 -38 -8 20 41 59 74 83", "output": "8" }, { "input": "10 10\n0 20 48 58 81 95 111 137 147 159", "output": "9" }, { "input": "100 1\n0 1 2 3...
109
0
3
1,042
214
System of Equations
[ "brute force" ]
null
null
Furik loves math lessons very much, so he doesn't attend them, unlike Rubik. But now Furik wants to get a good mark for math. For that Ms. Ivanova, his math teacher, gave him a new task. Furik solved the task immediately. Can you? You are given a system of equations: You should count, how many there are pairs of integers (*a*,<=*b*) (0<=≀<=*a*,<=*b*) which satisfy the system.
A single line contains two integers *n*,<=*m* (1<=≀<=*n*,<=*m*<=≀<=1000) β€” the parameters of the system. The numbers on the line are separated by a space.
On a single line print the answer to the problem.
[ "9 3\n", "14 28\n", "4 20\n" ]
[ "1\n", "1\n", "0\n" ]
In the first sample the suitable pair is integers (3, 0). In the second sample the suitable pair is integers (3, 5). In the third sample there is no suitable pair.
[ { "input": "9 3", "output": "1" }, { "input": "14 28", "output": "1" }, { "input": "4 20", "output": "0" }, { "input": "18 198", "output": "1" }, { "input": "22 326", "output": "1" }, { "input": "26 104", "output": "1" }, { "input": "14 10"...
154
0
0
1,043
527
Clique Problem
[ "data structures", "dp", "greedy", "implementation", "sortings" ]
null
null
The clique problem is one of the most well-known NP-complete problems. Under some simplification it can be formulated as follows. Consider an undirected graph *G*. It is required to find a subset of vertices *C* of the maximum size such that any two of them are connected by an edge in graph *G*. Sounds simple, doesn't it? Nobody yet knows an algorithm that finds a solution to this problem in polynomial time of the size of the graph. However, as with many other NP-complete problems, the clique problem is easier if you consider a specific type of a graph. Consider *n* distinct points on a line. Let the *i*-th point have the coordinate *x**i* and weight *w**i*. Let's form graph *G*, whose vertices are these points and edges connect exactly the pairs of points (*i*,<=*j*), such that the distance between them is not less than the sum of their weights, or more formally: |*x**i*<=-<=*x**j*|<=β‰₯<=*w**i*<=+<=*w**j*. Find the size of the maximum clique in such graph.
The first line contains the integer *n* (1<=≀<=*n*<=≀<=200<=000) β€” the number of points. Each of the next *n* lines contains two numbers *x**i*, *w**i* (0<=≀<=*x**i*<=≀<=109,<=1<=≀<=*w**i*<=≀<=109) β€” the coordinate and the weight of a point. All *x**i* are different.
Print a single number β€” the number of vertexes in the maximum clique of the given graph.
[ "4\n2 3\n3 1\n6 1\n0 2\n" ]
[ "3\n" ]
If you happen to know how to solve this problem without using the specific properties of the graph formulated in the problem statement, then you are able to get a prize of one million dollars! The picture for the sample test.
[ { "input": "4\n2 3\n3 1\n6 1\n0 2", "output": "3" }, { "input": "1\n42 23", "output": "1" }, { "input": "2\n1 5\n2 6", "output": "1" }, { "input": "2\n1 5\n12 6", "output": "2" }, { "input": "1\n0 1", "output": "1" }, { "input": "1\n1000000000 10000000...
46
0
0
1,044
703
Mishka and trip
[ "implementation", "math" ]
null
null
Little Mishka is a great traveller and she visited many countries. After thinking about where to travel this time, she chose XXXΒ β€” beautiful, but little-known northern country. Here are some interesting facts about XXX: 1. XXX consists of *n* cities, *k* of whose (just imagine!) are capital cities. 1. All of cities in the country are beautiful, but each is beautiful in its own way. Beauty value of *i*-th city equals to *c**i*. 1. All the cities are consecutively connected by the roads, including 1-st and *n*-th city, forming a cyclic route 1<=β€”<=2<=β€”<=...<=β€”<=*n*<=β€”<=1. Formally, for every 1<=≀<=*i*<=&lt;<=*n* there is a road between *i*-th and *i*<=+<=1-th city, and another one between 1-st and *n*-th city. 1. Each capital city is connected with each other city directly by the roads. Formally, if city *x* is a capital city, then for every 1<=≀<=*i*<=≀<=*n*,<=<=*i*<=β‰ <=*x*, there is a road between cities *x* and *i*. 1. There is at most one road between any two cities. 1. Price of passing a road directly depends on beauty values of cities it connects. Thus if there is a road between cities *i* and *j*, price of passing it equals *c**i*Β·*c**j*. Mishka started to gather her things for a trip, but didn't still decide which route to follow and thus she asked you to help her determine summary price of passing each of the roads in XXX. Formally, for every pair of cities *a* and *b* (*a*<=&lt;<=*b*), such that there is a road between *a* and *b* you are to find sum of products *c**a*Β·*c**b*. Will you help her?
The first line of the input contains two integers *n* and *k* (3<=≀<=*n*<=≀<=100<=000,<=1<=≀<=*k*<=≀<=*n*)Β β€” the number of cities in XXX and the number of capital cities among them. The second line of the input contains *n* integers *c*1,<=*c*2,<=...,<=*c**n* (1<=≀<=*c**i*<=≀<=10<=000)Β β€” beauty values of the cities. The third line of the input contains *k* distinct integers *id*1,<=*id*2,<=...,<=*id**k* (1<=≀<=*id**i*<=≀<=*n*)Β β€” indices of capital cities. Indices are given in ascending order.
Print the only integerΒ β€” summary price of passing each of the roads in XXX.
[ "4 1\n2 3 1 2\n3\n", "5 2\n3 5 2 2 4\n1 4\n" ]
[ "17", "71" ]
This image describes first sample case: <img class="tex-graphics" src="https://espresso.codeforces.com/9dcb0e62694349977e064303a74efd880af5eb03.png" style="max-width: 100.0%;max-height: 100.0%;"/> It is easy to see that summary price is equal to 17. This image describes second sample case: <img class="tex-graphics" src="https://espresso.codeforces.com/c30146637f3647c2fc77818bbbf3c080f94f116e.png" style="max-width: 100.0%;max-height: 100.0%;"/> It is easy to see that summary price is equal to 71.
[ { "input": "4 1\n2 3 1 2\n3", "output": "17" }, { "input": "5 2\n3 5 2 2 4\n1 4", "output": "71" }, { "input": "3 1\n1 1 1\n1", "output": "3" }, { "input": "3 3\n1 1 1\n1 2 3", "output": "3" }, { "input": "7 7\n6 9 2 7 4 8 7\n1 2 3 4 5 6 7", "output": "775" ...
46
0
0
1,045
637
Promocodes with Mistakes
[ "*special", "brute force", "constructive algorithms", "implementation" ]
null
null
During a New Year special offer the "Sudislavl Bars" offered *n* promo codes. Each promo code consists of exactly six digits and gives right to one free cocktail at the bar "Mosquito Shelter". Of course, all the promocodes differ. As the "Mosquito Shelter" opens only at 9, and partying in Sudislavl usually begins at as early as 6, many problems may arise as to how to type a promotional code without errors. It is necessary to calculate such maximum *k*, that the promotional code could be uniquely identified if it was typed with no more than *k* errors. At that, *k*<==<=0 means that the promotional codes must be entered exactly. A mistake in this problem should be considered as entering the wrong numbers. For example, value "123465" contains two errors relative to promocode "123456". Regardless of the number of errors the entered value consists of exactly six digits.
The first line of the output contains number *n* (1<=≀<=*n*<=≀<=1000)Β β€” the number of promocodes. Each of the next *n* lines contains a single promocode, consisting of exactly 6 digits. It is guaranteed that all the promocodes are distinct. Promocodes can start from digit "0".
Print the maximum *k* (naturally, not exceeding the length of the promocode), such that any promocode can be uniquely identified if it is typed with at most *k* mistakes.
[ "2\n000000\n999999\n", "6\n211111\n212111\n222111\n111111\n112111\n121111\n" ]
[ "2\n", "0\n" ]
In the first sample *k* &lt; 3, so if a bar customer types in value "090909", then it will be impossible to define which promocode exactly corresponds to it.
[ { "input": "2\n000000\n999999", "output": "2" }, { "input": "6\n211111\n212111\n222111\n111111\n112111\n121111", "output": "0" }, { "input": "1\n123456", "output": "6" }, { "input": "2\n000000\n099999", "output": "2" }, { "input": "2\n000000\n009999", "output"...
31
6,963,200
-1
1,048
527
Playing with Paper
[ "implementation", "math" ]
null
null
One day Vasya was sitting on a not so interesting Maths lesson and making an origami from a rectangular *a* mm <=Γ—<= *b* mm sheet of paper (*a*<=&gt;<=*b*). Usually the first step in making an origami is making a square piece of paper from the rectangular sheet by folding the sheet along the bisector of the right angle, and cutting the excess part. After making a paper ship from the square piece, Vasya looked on the remaining (*a*<=-<=*b*) mm <=Γ—<= *b* mm strip of paper. He got the idea to use this strip of paper in the same way to make an origami, and then use the remainder (if it exists) and so on. At the moment when he is left with a square piece of paper, he will make the last ship from it and stop. Can you determine how many ships Vasya will make during the lesson?
The first line of the input contains two integers *a*, *b* (1<=≀<=*b*<=&lt;<=*a*<=≀<=1012) β€” the sizes of the original sheet of paper.
Print a single integer β€” the number of ships that Vasya will make.
[ "2 1\n", "10 7\n", "1000000000000 1\n" ]
[ "2\n", "6\n", "1000000000000\n" ]
Pictures to the first and second sample test.
[ { "input": "2 1", "output": "2" }, { "input": "10 7", "output": "6" }, { "input": "1000000000000 1", "output": "1000000000000" }, { "input": "3 1", "output": "3" }, { "input": "4 1", "output": "4" }, { "input": "3 2", "output": "3" }, { "in...
61
0
-1
1,049
492
Vanya and Lanterns
[ "binary search", "implementation", "math", "sortings" ]
null
null
Vanya walks late at night along a straight street of length *l*, lit by *n* lanterns. Consider the coordinate system with the beginning of the street corresponding to the point 0, and its end corresponding to the point *l*. Then the *i*-th lantern is at the point *a**i*. The lantern lights all points of the street that are at the distance of at most *d* from it, where *d* is some positive number, common for all lanterns. Vanya wonders: what is the minimum light radius *d* should the lanterns have to light the whole street?
The first line contains two integers *n*, *l* (1<=≀<=*n*<=≀<=1000, 1<=≀<=*l*<=≀<=109)Β β€” the number of lanterns and the length of the street respectively. The next line contains *n* integers *a**i* (0<=≀<=*a**i*<=≀<=*l*). Multiple lanterns can be located at the same point. The lanterns may be located at the ends of the street.
Print the minimum light radius *d*, needed to light the whole street. The answer will be considered correct if its absolute or relative error doesn't exceed 10<=-<=9.
[ "7 15\n15 5 3 7 9 14 0\n", "2 5\n2 5\n" ]
[ "2.5000000000\n", "2.0000000000\n" ]
Consider the second sample. At *d* = 2 the first lantern will light the segment [0, 4] of the street, and the second lantern will light segment [3, 5]. Thus, the whole street will be lit.
[ { "input": "7 15\n15 5 3 7 9 14 0", "output": "2.5000000000" }, { "input": "2 5\n2 5", "output": "2.0000000000" }, { "input": "46 615683844\n431749087 271781274 274974690 324606253 480870261 401650581 13285442 478090364 266585394 425024433 588791449 492057200 391293435 563090494 317950 1...
46
0
0
1,051
381
Sereja and Dima
[ "greedy", "implementation", "two pointers" ]
null
null
Sereja and Dima play a game. The rules of the game are very simple. The players have *n* cards in a row. Each card contains a number, all numbers on the cards are distinct. The players take turns, Sereja moves first. During his turn a player can take one card: either the leftmost card in a row, or the rightmost one. The game ends when there is no more cards. The player who has the maximum sum of numbers on his cards by the end of the game, wins. Sereja and Dima are being greedy. Each of them chooses the card with the larger number during his move. Inna is a friend of Sereja and Dima. She knows which strategy the guys are using, so she wants to determine the final score, given the initial state of the game. Help her.
The first line contains integer *n* (1<=≀<=*n*<=≀<=1000) β€” the number of cards on the table. The second line contains space-separated numbers on the cards from left to right. The numbers on the cards are distinct integers from 1 to 1000.
On a single line, print two integers. The first number is the number of Sereja's points at the end of the game, the second number is the number of Dima's points at the end of the game.
[ "4\n4 1 2 10\n", "7\n1 2 3 4 5 6 7\n" ]
[ "12 5\n", "16 12\n" ]
In the first sample Sereja will take cards with numbers 10 and 2, so Sereja's sum is 12. Dima will take cards with numbers 4 and 1, so Dima's sum is 5.
[ { "input": "4\n4 1 2 10", "output": "12 5" }, { "input": "7\n1 2 3 4 5 6 7", "output": "16 12" }, { "input": "42\n15 29 37 22 16 5 26 31 6 32 19 3 45 36 33 14 25 20 48 7 42 11 24 28 9 18 8 21 47 17 38 40 44 4 35 1 43 39 41 27 12 13", "output": "613 418" }, { "input": "43\n32 ...
46
0
3
1,055
903
Boxes Packing
[ "greedy" ]
null
null
Mishka has got *n* empty boxes. For every *i* (1<=≀<=*i*<=≀<=*n*), *i*-th box is a cube with side length *a**i*. Mishka can put a box *i* into another box *j* if the following conditions are met: - *i*-th box is not put into another box; - *j*-th box doesn't contain any other boxes; - box *i* is smaller than box *j* (*a**i*<=&lt;<=*a**j*). Mishka can put boxes into each other an arbitrary number of times. He wants to minimize the number of visible boxes. A box is called visible iff it is not put into some another box. Help Mishka to determine the minimum possible number of visible boxes!
The first line contains one integer *n* (1<=≀<=*n*<=≀<=5000) β€” the number of boxes Mishka has got. The second line contains *n* integers *a*1, *a*2, ..., *a**n* (1<=≀<=*a**i*<=≀<=109), where *a**i* is the side length of *i*-th box.
Print the minimum possible number of visible boxes.
[ "3\n1 2 3\n", "4\n4 2 4 3\n" ]
[ "1\n", "2\n" ]
In the first example it is possible to put box 1 into box 2, and 2 into 3. In the second example Mishka can put box 2 into box 3, and box 4 into box 1.
[ { "input": "3\n1 2 3", "output": "1" }, { "input": "4\n4 2 4 3", "output": "2" }, { "input": "10\n58 58 58 58 58 58 58 58 58 58", "output": "10" }, { "input": "10\n86 89 89 86 86 89 86 86 89 89", "output": "5" }, { "input": "100\n981 288 186 186 292 876 341 288 98...
108
0
0
1,058
875
Classroom Watch
[ "brute force", "math" ]
null
null
Eighth-grader Vova is on duty today in the class. After classes, he went into the office to wash the board, and found on it the number *n*. He asked what is this number and the teacher of mathematics Inna Petrovna answered Vova that *n* is the answer to the arithmetic task for first-graders. In the textbook, a certain positive integer *x* was given. The task was to add *x* to the sum of the digits of the number *x* written in decimal numeral system. Since the number *n* on the board was small, Vova quickly guessed which *x* could be in the textbook. Now he wants to get a program which will search for arbitrary values of the number *n* for all suitable values of *x* or determine that such *x* does not exist. Write such a program for Vova.
The first line contains integer *n* (1<=≀<=*n*<=≀<=109).
In the first line print one integer *k*Β β€” number of different values of *x* satisfying the condition. In next *k* lines print these values in ascending order.
[ "21\n", "20\n" ]
[ "1\n15\n", "0\n" ]
In the first test case *x* = 15 there is only one variant: 15 + 1 + 5 = 21. In the second test case there are no such *x*.
[ { "input": "21", "output": "1\n15" }, { "input": "20", "output": "0" }, { "input": "1", "output": "0" }, { "input": "2", "output": "1\n1" }, { "input": "3", "output": "0" }, { "input": "100000001", "output": "2\n99999937\n100000000" }, { "i...
1,000
0
0
1,059
611
New Year and Days
[ "implementation" ]
null
null
Today is Wednesday, the third day of the week. What's more interesting is that tomorrow is the last day of the year 2015. Limak is a little polar bear. He enjoyed this year a lot. Now, he is so eager to the coming year 2016. Limak wants to prove how responsible a bear he is. He is going to regularly save candies for the entire year 2016! He considers various saving plans. He can save one candy either on some fixed day of the week or on some fixed day of the month. Limak chose one particular plan. He isn't sure how many candies he will save in the 2016 with his plan. Please, calculate it and tell him.
The only line of the input is in one of the following two formats: - "*x* of week" where *x* (1<=≀<=*x*<=≀<=7) denotes the day of the week. The 1-st day is Monday and the 7-th one is Sunday. - "*x* of month" where *x* (1<=≀<=*x*<=≀<=31) denotes the day of the month.
Print one integerΒ β€” the number of candies Limak will save in the year 2016.
[ "4 of week\n", "30 of month\n" ]
[ "52\n", "11\n" ]
Polar bears use the Gregorian calendar. It is the most common calendar and you likely use it too. You can read about it on Wikipedia if you want to – [https://en.wikipedia.org/wiki/Gregorian_calendar](https://en.wikipedia.org/wiki/Gregorian_calendar). The week starts with Monday. In the first sample Limak wants to save one candy on each Thursday (the 4-th day of the week). There are 52 Thursdays in the 2016. Thus, he will save 52 candies in total. In the second sample Limak wants to save one candy on the 30-th day of each month. There is the 30-th day in exactly 11 months in the 2016Β β€” all months but February. It means that Limak will save 11 candies in total.
[ { "input": "4 of week", "output": "52" }, { "input": "30 of month", "output": "11" }, { "input": "17 of month", "output": "12" }, { "input": "31 of month", "output": "7" }, { "input": "6 of week", "output": "53" }, { "input": "1 of week", "output":...
46
0
0
1,062
219
k-String
[ "implementation", "strings" ]
null
null
A string is called a *k*-string if it can be represented as *k* concatenated copies of some string. For example, the string "aabaabaabaab" is at the same time a 1-string, a 2-string and a 4-string, but it is not a 3-string, a 5-string, or a 6-string and so on. Obviously any string is a 1-string. You are given a string *s*, consisting of lowercase English letters and a positive integer *k*. Your task is to reorder the letters in the string *s* in such a way that the resulting string is a *k*-string.
The first input line contains integer *k* (1<=≀<=*k*<=≀<=1000). The second line contains *s*, all characters in *s* are lowercase English letters. The string length *s* satisfies the inequality 1<=≀<=|*s*|<=≀<=1000, where |*s*| is the length of string *s*.
Rearrange the letters in string *s* in such a way that the result is a *k*-string. Print the result on a single output line. If there are multiple solutions, print any of them. If the solution doesn't exist, print "-1" (without quotes).
[ "2\naazz\n", "3\nabcabcabz\n" ]
[ "azaz\n", "-1\n" ]
none
[ { "input": "2\naazz", "output": "azaz" }, { "input": "3\nabcabcabz", "output": "-1" }, { "input": "1\na", "output": "a" }, { "input": "2\nabba", "output": "abab" }, { "input": "2\naaab", "output": "-1" }, { "input": "7\nabacaba", "output": "-1" }...
92
0
3
1,063
353
Two Heaps
[ "combinatorics", "constructive algorithms", "greedy", "implementation", "math", "sortings" ]
null
null
Valera has 2Β·*n* cubes, each cube contains an integer from 10 to 99. He arbitrarily chooses *n* cubes and puts them in the first heap. The remaining cubes form the second heap. Valera decided to play with cubes. During the game he takes a cube from the first heap and writes down the number it has. Then he takes a cube from the second heap and write out its two digits near two digits he had written (to the right of them). In the end he obtained a single fourdigit integer β€” the first two digits of it is written on the cube from the first heap, and the second two digits of it is written on the second cube from the second heap. Valera knows arithmetic very well. So, he can easily count the number of distinct fourdigit numbers he can get in the game. The other question is: how to split cubes into two heaps so that this number (the number of distinct fourdigit integers Valera can get) will be as large as possible?
The first line contains integer *n* (1<=≀<=*n*<=≀<=100). The second line contains 2Β·*n* space-separated integers *a**i* (10<=≀<=*a**i*<=≀<=99), denoting the numbers on the cubes.
In the first line print a single number β€” the maximum possible number of distinct four-digit numbers Valera can obtain. In the second line print 2Β·*n* numbers *b**i* (1<=≀<=*b**i*<=≀<=2). The numbers mean: the *i*-th cube belongs to the *b**i*-th heap in your division. If there are multiple optimal ways to split the cubes into the heaps, print any of them.
[ "1\n10 99\n", "2\n13 24 13 45\n" ]
[ "1\n2 1 \n", "4\n1 2 2 1 \n" ]
In the first test case Valera can put the first cube in the first heap, and second cube β€” in second heap. In this case he obtain number 1099. If he put the second cube in the first heap, and the first cube in the second heap, then he can obtain number 9910. In both cases the maximum number of distinct integers is equal to one. In the second test case Valera can obtain numbers 1313, 1345, 2413, 2445. Note, that if he put the first and the third cubes in the first heap, he can obtain only two numbers 1324 and 1345.
[ { "input": "1\n10 99", "output": "1\n2 1 " }, { "input": "2\n13 24 13 45", "output": "4\n1 2 2 1 " }, { "input": "5\n21 60 18 21 17 39 58 74 62 34", "output": "25\n1 1 1 2 2 1 2 1 2 2 " }, { "input": "10\n26 43 29 92 22 27 95 56 72 55 93 51 91 30 70 77 32 69 87 98", "outp...
312
20,172,800
3
1,067
771
Bear and Friendship Condition
[ "dfs and similar", "dsu", "graphs" ]
null
null
Bear Limak examines a social network. Its main functionality is that two members can become friends (then they can talk with each other and share funny pictures). There are *n* members, numbered 1 through *n*. *m* pairs of members are friends. Of course, a member can't be a friend with themselves. Let A-B denote that members A and B are friends. Limak thinks that a network is reasonable if and only if the following condition is satisfied: For every three distinct members (X, Y, Z), if X-Y and Y-Z then also X-Z. For example: if Alan and Bob are friends, and Bob and Ciri are friends, then Alan and Ciri should be friends as well. Can you help Limak and check if the network is reasonable? Print "YES" or "NO" accordingly, without the quotes.
The first line of the input contain two integers *n* and *m* (3<=≀<=*n*<=≀<=150<=000, )Β β€” the number of members and the number of pairs of members that are friends. The *i*-th of the next *m* lines contains two distinct integers *a**i* and *b**i* (1<=≀<=*a**i*,<=*b**i*<=≀<=*n*,<=*a**i*<=β‰ <=*b**i*). Members *a**i* and *b**i* are friends with each other. No pair of members will appear more than once in the input.
If the given network is reasonable, print "YES" in a single line (without the quotes). Otherwise, print "NO" in a single line (without the quotes).
[ "4 3\n1 3\n3 4\n1 4\n", "4 4\n3 1\n2 3\n3 4\n1 2\n", "10 4\n4 3\n5 10\n8 9\n1 2\n", "3 2\n1 2\n2 3\n" ]
[ "YES\n", "NO\n", "YES\n", "NO\n" ]
The drawings below show the situation in the first sample (on the left) and in the second sample (on the right). Each edge represents two members that are friends. The answer is "NO" in the second sample because members (2, 3) are friends and members (3, 4) are friends, while members (2, 4) are not.
[ { "input": "4 3\n1 3\n3 4\n1 4", "output": "YES" }, { "input": "4 4\n3 1\n2 3\n3 4\n1 2", "output": "NO" }, { "input": "10 4\n4 3\n5 10\n8 9\n1 2", "output": "YES" }, { "input": "3 2\n1 2\n2 3", "output": "NO" }, { "input": "3 0", "output": "YES" }, { ...
1,000
8,499,200
0
1,069
734
Anton and Danik
[ "implementation", "strings" ]
null
null
Anton likes to play chess, and so does his friend Danik. Once they have played *n* games in a row. For each game it's known who was the winnerΒ β€” Anton or Danik. None of the games ended with a tie. Now Anton wonders, who won more games, he or Danik? Help him determine this.
The first line of the input contains a single integer *n* (1<=≀<=*n*<=≀<=100<=000)Β β€” the number of games played. The second line contains a string *s*, consisting of *n* uppercase English letters 'A' and 'D'Β β€” the outcome of each of the games. The *i*-th character of the string is equal to 'A' if the Anton won the *i*-th game and 'D' if Danik won the *i*-th game.
If Anton won more games than Danik, print "Anton" (without quotes) in the only line of the output. If Danik won more games than Anton, print "Danik" (without quotes) in the only line of the output. If Anton and Danik won the same number of games, print "Friendship" (without quotes).
[ "6\nADAAAA\n", "7\nDDDAADA\n", "6\nDADADA\n" ]
[ "Anton\n", "Danik\n", "Friendship\n" ]
In the first sample, Anton won 6 games, while DanikΒ β€” only 1. Hence, the answer is "Anton". In the second sample, Anton won 3 games and Danik won 4 games, so the answer is "Danik". In the third sample, both Anton and Danik won 3 games and the answer is "Friendship".
[ { "input": "6\nADAAAA", "output": "Anton" }, { "input": "7\nDDDAADA", "output": "Danik" }, { "input": "6\nDADADA", "output": "Friendship" }, { "input": "10\nDDDDADDADD", "output": "Danik" }, { "input": "40\nAAAAAAAAADDAAAAAAAAAAADADDAAAAAAAAAAADAA", "output": ...
46
204,800
3
1,073
265
Roadside Trees (Simplified Edition)
[ "greedy", "implementation" ]
null
null
Squirrel Liss loves nuts. There are *n* trees (numbered 1 to *n* from west to east) along a street and there is a delicious nut on the top of each tree. The height of the tree *i* is *h**i*. Liss wants to eat all nuts. Now Liss is on the root of the tree with the number 1. In one second Liss can perform one of the following actions: - Walk up or down one unit on a tree. - Eat a nut on the top of the current tree. - Jump to the next tree. In this action the height of Liss doesn't change. More formally, when Liss is at height *h* of the tree *i* (1<=≀<=*i*<=≀<=*n*<=-<=1), she jumps to height *h* of the tree *i*<=+<=1. This action can't be performed if *h*<=&gt;<=*h**i*<=+<=1. Compute the minimal time (in seconds) required to eat all nuts.
The first line contains an integer *n* (1<=<=≀<=<=*n*<=≀<=105) β€” the number of trees. Next *n* lines contains the height of trees: *i*-th line contains an integer *h**i* (1<=≀<=*h**i*<=≀<=104) β€” the height of the tree with the number *i*.
Print a single integer β€” the minimal time required to eat all nuts in seconds.
[ "2\n1\n2\n", "5\n2\n1\n2\n1\n1\n" ]
[ "5\n", "14\n" ]
none
[ { "input": "2\n1\n2", "output": "5" }, { "input": "5\n2\n1\n2\n1\n1", "output": "14" }, { "input": "1\n1", "output": "2" } ]
248
6,963,200
0
1,077
343
Read Time
[ "binary search", "greedy", "two pointers" ]
null
null
Mad scientist Mike does not use slow hard disks. His modification of a hard drive has not one, but *n* different heads that can read data in parallel. When viewed from the side, Mike's hard drive is an endless array of tracks. The tracks of the array are numbered from left to right with integers, starting with 1. In the initial state the *i*-th reading head is above the track number *h**i*. For each of the reading heads, the hard drive's firmware can move the head exactly one track to the right or to the left, or leave it on the current track. During the operation each head's movement does not affect the movement of the other heads: the heads can change their relative order; there can be multiple reading heads above any of the tracks. A track is considered read if at least one head has visited this track. In particular, all of the tracks numbered *h*1, *h*2, ..., *h**n* have been read at the beginning of the operation. Mike needs to read the data on *m* distinct tracks with numbers *p*1, *p*2, ..., *p**m*. Determine the minimum time the hard drive firmware needs to move the heads and read all the given tracks. Note that an arbitrary number of other tracks can also be read.
The first line of the input contains two space-separated integers *n*, *m* (1<=≀<=*n*,<=*m*<=≀<=105) β€” the number of disk heads and the number of tracks to read, accordingly. The second line contains *n* distinct integers *h**i* in ascending order (1<=≀<=*h**i*<=≀<=1010, *h**i*<=&lt;<=*h**i*<=+<=1) β€” the initial positions of the heads. The third line contains *m* distinct integers *p**i* in ascending order (1<=≀<=*p**i*<=≀<=1010, *p**i*<=&lt;<=*p**i*<=+<=1) - the numbers of tracks to read. Please, do not use the %lld specifier to read or write 64-bit integers in Π‘++. It is recommended to use the cin, cout streams or the %I64d specifier.
Print a single number β€” the minimum time required, in seconds, to read all the needed tracks.
[ "3 4\n2 5 6\n1 3 6 8\n", "3 3\n1 2 3\n1 2 3\n", "1 2\n165\n142 200\n" ]
[ "2\n", "0\n", "81\n" ]
The first test coincides with the figure. In this case the given tracks can be read in 2 seconds in the following way: 1. during the first second move the 1-st head to the left and let it stay there; 1. move the second head to the left twice; 1. move the third head to the right twice (note that the 6-th track has already been read at the beginning). One cannot read the tracks in 1 second as the 3-rd head is at distance 2 from the 8-th track.
[ { "input": "3 4\n2 5 6\n1 3 6 8", "output": "2" }, { "input": "3 3\n1 2 3\n1 2 3", "output": "0" }, { "input": "1 2\n165\n142 200", "output": "81" }, { "input": "1 2\n5000000000\n1 10000000000", "output": "14999999998" }, { "input": "2 4\n3 12\n1 7 8 14", "out...
233
20,172,800
3
1,079
678
Iterated Linear Function
[ "math", "number theory" ]
null
null
Consider a linear function *f*(*x*)<==<=*Ax*<=+<=*B*. Let's define *g*(0)(*x*)<==<=*x* and *g*(*n*)(*x*)<==<=*f*(*g*(*n*<=-<=1)(*x*)) for *n*<=&gt;<=0. For the given integer values *A*, *B*, *n* and *x* find the value of *g*(*n*)(*x*) modulo 109<=+<=7.
The only line contains four integers *A*, *B*, *n* and *x* (1<=≀<=*A*,<=*B*,<=*x*<=≀<=109,<=1<=≀<=*n*<=≀<=1018) β€” the parameters from the problem statement. Note that the given value *n* can be too large, 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.
Print the only integer *s* β€” the value *g*(*n*)(*x*) modulo 109<=+<=7.
[ "3 4 1 1\n", "3 4 2 1\n", "3 4 3 1\n" ]
[ "7\n", "25\n", "79\n" ]
none
[ { "input": "3 4 1 1", "output": "7" }, { "input": "3 4 2 1", "output": "25" }, { "input": "3 4 3 1", "output": "79" }, { "input": "1 1 1 1", "output": "2" }, { "input": "3 10 723 6", "output": "443623217" }, { "input": "14 81 51 82", "output": "908...
140
0
3
1,082
424
Squats
[ "implementation" ]
null
null
Pasha has many hamsters and he makes them work out. Today, *n* hamsters (*n* is even) came to work out. The hamsters lined up and each hamster either sat down or stood up. For another exercise, Pasha needs exactly hamsters to stand up and the other hamsters to sit down. In one minute, Pasha can make some hamster ether sit down or stand up. How many minutes will he need to get what he wants if he acts optimally well?
The first line contains integer *n* (2<=≀<=*n*<=≀<=200; *n* is even). The next line contains *n* characters without spaces. These characters describe the hamsters' position: the *i*-th character equals 'X', if the *i*-th hamster in the row is standing, and 'x', if he is sitting.
In the first line, print a single integer β€” the minimum required number of minutes. In the second line, print a string that describes the hamsters' position after Pasha makes the required changes. If there are multiple optimal positions, print any of them.
[ "4\nxxXx\n", "2\nXX\n", "6\nxXXxXx\n" ]
[ "1\nXxXx\n", "1\nxX\n", "0\nxXXxXx\n" ]
none
[ { "input": "4\nxxXx", "output": "1\nXxXx" }, { "input": "2\nXX", "output": "1\nxX" }, { "input": "6\nxXXxXx", "output": "0\nxXXxXx" }, { "input": "4\nxXXX", "output": "1\nxxXX" }, { "input": "2\nXx", "output": "0\nXx" }, { "input": "22\nXXxXXxxXxXxXXXX...
46
0
3
1,083
67
Partial Teacher
[ "dp", "graphs", "greedy", "implementation" ]
A. Partial Teacher
1
256
A teacher decides to give toffees to his students. He asks *n* students to stand in a queue. Since the teacher is very partial, he follows the following rule to distribute toffees. He looks at the first two students and gives more toffees to the student having higher marks than the other one. If they have the same marks they get the same number of toffees. The same procedure is followed for each pair of adjacent students starting from the first one to the last one. It is given that each student receives at least one toffee. You have to find the number of toffees given to each student by the teacher such that the total number of toffees is minimum.
The first line of input contains the number of students *n* (2<=≀<=*n*<=≀<=1000). The second line gives (*n*<=-<=1) characters consisting of "L", "R" and "=". For each pair of adjacent students "L" means that the left student has higher marks, "R" means that the right student has higher marks and "=" means that both have equal marks.
Output consists of *n* integers separated by a space representing the number of toffees each student receives in the queue starting from the first one to the last one.
[ "5\nLRLR\n", "5\n=RRR\n" ]
[ "2 1 2 1 2\n", "1 1 2 3 4\n" ]
none
[ { "input": "5\nLRLR", "output": "2 1 2 1 2" }, { "input": "5\n=RRR", "output": "1 1 2 3 4" }, { "input": "6\nRLRL=", "output": "1 2 1 2 1 1" }, { "input": "3\nR=", "output": "1 2 2" }, { "input": "7\nRR==RR", "output": "1 2 3 3 3 4 5" }, { "input": "16...
280
0
0
1,087
601
The Two Routes
[ "graphs", "shortest paths" ]
null
null
In Absurdistan, there are *n* towns (numbered 1 through *n*) and *m* bidirectional railways. There is also an absurdly simple road networkΒ β€” for each pair of different towns *x* and *y*, there is a bidirectional road between towns *x* and *y* if and only if there is no railway between them. Travelling to a different town using one railway or one road always takes exactly one hour. A train and a bus leave town 1 at the same time. They both have the same destination, town *n*, and don't make any stops on the way (but they can wait in town *n*). The train can move only along railways and the bus can move only along roads. You've been asked to plan out routes for the vehicles; each route can use any road/railway multiple times. One of the most important aspects to consider is safetyΒ β€” in order to avoid accidents at railway crossings, the train and the bus must not arrive at the same town (except town *n*) simultaneously. Under these constraints, what is the minimum number of hours needed for both vehicles to reach town *n* (the maximum of arrival times of the bus and the train)? Note, that bus and train are not required to arrive to the town *n* at the same moment of time, but are allowed to do so.
The first line of the input contains two integers *n* and *m* (2<=≀<=*n*<=≀<=400, 0<=≀<=*m*<=≀<=*n*(*n*<=-<=1)<=/<=2)Β β€” the number of towns and the number of railways respectively. Each of the next *m* lines contains two integers *u* and *v*, denoting a railway between towns *u* and *v* (1<=≀<=*u*,<=*v*<=≀<=*n*, *u*<=β‰ <=*v*). You may assume that there is at most one railway connecting any two towns.
Output one integerΒ β€” the smallest possible time of the later vehicle's arrival in town *n*. If it's impossible for at least one of the vehicles to reach town *n*, output <=-<=1.
[ "4 2\n1 3\n3 4\n", "4 6\n1 2\n1 3\n1 4\n2 3\n2 4\n3 4\n", "5 5\n4 2\n3 5\n4 5\n5 1\n1 2\n" ]
[ "2\n", "-1\n", "3\n" ]
In the first sample, the train can take the route <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7c0aa60a06309ef607b7159fd7f3687ea0d943ce.png" style="max-width: 100.0%;max-height: 100.0%;"/> and the bus can take the route <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/a26c2f3e93c9d9be6c21cb5d2bd6ac1f99f4ff55.png" style="max-width: 100.0%;max-height: 100.0%;"/>. Note that they can arrive at town 4 at the same time. In the second sample, Absurdistan is ruled by railwaymen. There are no roads, so there's no way for the bus to reach town 4.
[ { "input": "4 2\n1 3\n3 4", "output": "2" }, { "input": "4 6\n1 2\n1 3\n1 4\n2 3\n2 4\n3 4", "output": "-1" }, { "input": "5 5\n4 2\n3 5\n4 5\n5 1\n1 2", "output": "3" }, { "input": "5 4\n1 2\n3 2\n3 4\n5 4", "output": "4" }, { "input": "3 1\n1 2", "output": "...
108
0
0
1,093
52
123-sequence
[ "implementation" ]
A. 123-sequence
2
256
There is a given sequence of integers *a*1,<=*a*2,<=...,<=*a**n*, where every number is from 1 to 3 inclusively. You have to replace the minimum number of numbers in it so that all the numbers in the sequence are equal to each other.
The first line contains an integer *n* (1<=≀<=*n*<=≀<=106). The second line contains a sequence of integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≀<=*a**i*<=≀<=3).
Print the minimum number of replacements needed to be performed to make all the numbers in the sequence equal.
[ "9\n1 3 2 2 2 1 1 2 3\n" ]
[ "5\n" ]
In the example all the numbers equal to 1 and 3 should be replaced by 2.
[ { "input": "9\n1 3 2 2 2 1 1 2 3", "output": "5" }, { "input": "6\n3 3 2 2 1 3", "output": "3" }, { "input": "12\n3 1 3 1 2 1 3 2 2 1 2 1", "output": "7" }, { "input": "15\n3 2 1 1 1 1 3 2 2 3 3 1 2 3 2", "output": "10" }, { "input": "2\n2 1", "output": "1" ...
374
11,059,200
3.885901
1,094
849
Tell Your World
[ "brute force", "geometry" ]
null
null
Connect the countless points with lines, till we reach the faraway yonder. There are *n* points on a coordinate plane, the *i*-th of which being (*i*,<=*y**i*). Determine whether it's possible to draw two parallel and non-overlapping lines, such that every point in the set lies on exactly one of them, and each of them passes through at least one point in the set.
The first line of input contains a positive integer *n* (3<=≀<=*n*<=≀<=1<=000) β€” the number of points. The second line contains *n* space-separated integers *y*1,<=*y*2,<=...,<=*y**n* (<=-<=109<=≀<=*y**i*<=≀<=109) β€” the vertical coordinates of each point.
Output "Yes" (without quotes) if it's possible to fulfill the requirements, and "No" otherwise. You can print each letter in any case (upper or lower).
[ "5\n7 5 8 6 9\n", "5\n-1 -2 0 0 -5\n", "5\n5 4 3 2 1\n", "5\n1000000000 0 0 0 0\n" ]
[ "Yes\n", "No\n", "No\n", "Yes\n" ]
In the first example, there are five points: (1, 7), (2, 5), (3, 8), (4, 6) and (5, 9). It's possible to draw a line that passes through points 1, 3, 5, and another one that passes through points 2, 4 and is parallel to the first one. In the second example, while it's possible to draw two lines that cover all points, they cannot be made parallel. In the third example, it's impossible to satisfy both requirements at the same time.
[ { "input": "5\n7 5 8 6 9", "output": "Yes" }, { "input": "5\n-1 -2 0 0 -5", "output": "No" }, { "input": "5\n5 4 3 2 1", "output": "No" }, { "input": "5\n1000000000 0 0 0 0", "output": "Yes" }, { "input": "5\n1000000000 1 0 -999999999 -1000000000", "output": "...
93
0
0
1,097
1,000
Light It Up
[ "greedy" ]
null
null
Recently, you bought a brand new smart lamp with programming features. At first, you set up a schedule to the lamp. Every day it will turn power on at moment $0$ and turn power off at moment $M$. Moreover, the lamp allows you to set a program of switching its state (states are "lights on" and "lights off"). Unfortunately, some program is already installed into the lamp. The lamp allows only good programs. Good program can be represented as a non-empty array $a$, where $0 &lt; a_1 &lt; a_2 &lt; \dots &lt; a_{|a|} &lt; M$. All $a_i$ must be integers. Of course, preinstalled program is a good program. The lamp follows program $a$ in next manner: at moment $0$ turns power and light on. Then at moment $a_i$ the lamp flips its state to opposite (if it was lit, it turns off, and vice versa). The state of the lamp flips instantly: for example, if you turn the light off at moment $1$ and then do nothing, the total time when the lamp is lit will be $1$. Finally, at moment $M$ the lamp is turning its power off regardless of its state. Since you are not among those people who read instructions, and you don't understand the language it's written in, you realize (after some testing) the only possible way to alter the preinstalled program. You can insert at most one element into the program $a$, so it still should be a good program after alteration. Insertion can be done between any pair of consecutive elements of $a$, or even at the begining or at the end of $a$. Find such a way to alter the program that the total time when the lamp is lit is maximum possible. Maybe you should leave program untouched. If the lamp is lit from $x$ till moment $y$, then its lit for $y - x$ units of time. Segments of time when the lamp is lit are summed up.
First line contains two space separated integers $n$ and $M$ ($1 \le n \le 10^5$, $2 \le M \le 10^9$) β€” the length of program $a$ and the moment when power turns off. Second line contains $n$ space separated integers $a_1, a_2, \dots, a_n$ ($0 &lt; a_1 &lt; a_2 &lt; \dots &lt; a_n &lt; M$) β€” initially installed program $a$.
Print the only integer β€” maximum possible total time when the lamp is lit.
[ "3 10\n4 6 7\n", "2 12\n1 10\n", "2 7\n3 4\n" ]
[ "8\n", "9\n", "6\n" ]
In the first example, one of possible optimal solutions is to insert value $x = 3$ before $a_1$, so program will be $[3, 4, 6, 7]$ and time of lamp being lit equals $(3 - 0) + (6 - 4) + (10 - 7) = 8$. Other possible solution is to insert $x = 5$ in appropriate place. In the second example, there is only one optimal solution: to insert $x = 2$ between $a_1$ and $a_2$. Program will become $[1, 2, 10]$, and answer will be $(1 - 0) + (10 - 2) = 9$. In the third example, optimal answer is to leave program untouched, so answer will be $(3 - 0) + (7 - 4) = 6$.
[ { "input": "3 10\n4 6 7", "output": "8" }, { "input": "2 12\n1 10", "output": "9" }, { "input": "2 7\n3 4", "output": "6" }, { "input": "1 2\n1", "output": "1" }, { "input": "5 10\n1 3 5 6 8", "output": "6" }, { "input": "7 1000000000\n1 10001 10011 20...
31
4,505,600
0
1,102
0
none
[ "none" ]
null
null
Malek has recently found a treasure map. While he was looking for a treasure he found a locked door. There was a string *s* written on the door consisting of characters '(', ')' and '#'. Below there was a manual on how to open the door. After spending a long time Malek managed to decode the manual and found out that the goal is to replace each '#' with one or more ')' characters so that the final string becomes beautiful. Below there was also written that a string is called beautiful if for each *i* (1<=≀<=*i*<=≀<=|*s*|) there are no more ')' characters than '(' characters among the first *i* characters of *s* and also the total number of '(' characters is equal to the total number of ')' characters. Help Malek open the door by telling him for each '#' character how many ')' characters he must replace it with.
The first line of the input contains a string *s* (1<=≀<=|*s*|<=≀<=105). Each character of this string is one of the characters '(', ')' or '#'. It is guaranteed that *s* contains at least one '#' character.
If there is no way of replacing '#' characters which leads to a beautiful string print <=-<=1. Otherwise for each character '#' print a separate line containing a positive integer, the number of ')' characters this character must be replaced with. If there are several possible answers, you may output any of them.
[ "(((#)((#)\n", "()((#((#(#()\n", "#\n", "(#)\n" ]
[ "1\n2\n", "2\n2\n1", "-1\n", "-1\n" ]
|*s*| denotes the length of the string *s*.
[ { "input": "(((#)((#)", "output": "1\n2" }, { "input": "()((#((#(#()", "output": "1\n1\n3" }, { "input": "#", "output": "-1" }, { "input": "(#)", "output": "-1" }, { "input": "(((((#(#(#(#()", "output": "1\n1\n1\n5" }, { "input": "#))))", "output":...
155
307,200
0
1,103
433
Kitahara Haruki's Gift
[ "brute force", "implementation" ]
null
null
Kitahara Haruki has bought *n* apples for Touma Kazusa and Ogiso Setsuna. Now he wants to divide all the apples between the friends. Each apple weights 100 grams or 200 grams. Of course Kitahara Haruki doesn't want to offend any of his friend. Therefore the total weight of the apples given to Touma Kazusa must be equal to the total weight of the apples given to Ogiso Setsuna. But unfortunately Kitahara Haruki doesn't have a knife right now, so he cannot split any apple into some parts. Please, tell him: is it possible to divide all the apples in a fair way between his friends?
The first line contains an integer *n* (1<=≀<=*n*<=≀<=100) β€” the number of apples. The second line contains *n* integers *w*1,<=*w*2,<=...,<=*w**n* (*w**i*<==<=100 or *w**i*<==<=200), where *w**i* is the weight of the *i*-th apple.
In a single line print "YES" (without the quotes) if it is possible to divide all the apples between his friends. Otherwise print "NO" (without the quotes).
[ "3\n100 200 100\n", "4\n100 100 100 200\n" ]
[ "YES\n", "NO\n" ]
In the first test sample Kitahara Haruki can give the first and the last apple to Ogiso Setsuna and the middle apple to Touma Kazusa.
[ { "input": "3\n100 200 100", "output": "YES" }, { "input": "4\n100 100 100 200", "output": "NO" }, { "input": "1\n100", "output": "NO" }, { "input": "1\n200", "output": "NO" }, { "input": "2\n100 100", "output": "YES" }, { "input": "2\n200 200", "o...
46
0
0
1,106
350
Bombs
[ "greedy", "implementation", "sortings" ]
null
null
You've got a robot, its task is destroying bombs on a square plane. Specifically, the square plane contains *n* bombs, the *i*-th bomb is at point with coordinates (*x**i*,<=*y**i*). We know that no two bombs are at the same point and that no bomb is at point with coordinates (0,<=0). Initially, the robot is at point with coordinates (0,<=0). Also, let's mark the robot's current position as (*x*,<=*y*). In order to destroy all the bombs, the robot can perform three types of operations: 1. Operation has format "1 k dir". To perform the operation robot have to move in direction *dir* *k* (*k*<=β‰₯<=1) times. There are only 4 directions the robot can move in: "R", "L", "U", "D". During one move the robot can move from the current point to one of following points: (*x*<=+<=1,<=*y*), (*x*<=-<=1,<=*y*), (*x*,<=*y*<=+<=1), (*x*,<=*y*<=-<=1) (corresponding to directions). It is forbidden to move from point (*x*,<=*y*), if at least one point on the path (besides the destination point) contains a bomb. 1. Operation has format "2". To perform the operation robot have to pick a bomb at point (*x*,<=*y*) and put it in a special container. Thus, the robot can carry the bomb from any point to any other point. The operation cannot be performed if point (*x*,<=*y*) has no bomb. It is forbidden to pick a bomb if the robot already has a bomb in its container. 1. Operation has format "3". To perform the operation robot have to take a bomb out of the container and destroy it. You are allowed to perform this operation only if the robot is at point (0,<=0). It is forbidden to perform the operation if the container has no bomb. Help the robot and find the shortest possible sequence of operations he can perform to destroy all bombs on the coordinate plane.
The first line contains a single integer *n* (1<=≀<=*n*<=≀<=105) β€” the number of bombs on the coordinate plane. Next *n* lines contain two integers each. The *i*-th line contains numbers (*x**i*,<=*y**i*) (<=-<=109<=≀<=*x**i*,<=*y**i*<=≀<=109) β€” the coordinates of the *i*-th bomb. It is guaranteed that no two bombs are located at the same point and no bomb is at point (0,<=0).
In a single line print a single integer *k* β€” the minimum number of operations needed to destroy all bombs. On the next lines print the descriptions of these *k* operations. If there are multiple sequences, you can print any of them. It is guaranteed that there is the solution where *k*<=≀<=106.
[ "2\n1 1\n-1 -1\n", "3\n5 0\n0 5\n1 0\n" ]
[ "12\n1 1 R\n1 1 U\n2\n1 1 L\n1 1 D\n3\n1 1 L\n1 1 D\n2\n1 1 R\n1 1 U\n3\n", "12\n1 1 R\n2\n1 1 L\n3\n1 5 R\n2\n1 5 L\n3\n1 5 U\n2\n1 5 D\n3\n" ]
none
[ { "input": "2\n1 1\n-1 -1", "output": "12\n1 1 R\n1 1 U\n2\n1 1 L\n1 1 D\n3\n1 1 L\n1 1 D\n2\n1 1 R\n1 1 U\n3" }, { "input": "3\n5 0\n0 5\n1 0", "output": "12\n1 1 R\n2\n1 1 L\n3\n1 5 R\n2\n1 5 L\n3\n1 5 U\n2\n1 5 D\n3" }, { "input": "1\n-277226476 314722425", "output": "6\n1 2772264...
218
0
0
1,107
762
USB vs. PS/2
[ "greedy", "implementation", "sortings", "two pointers" ]
null
null
Due to the increase in the number of students of Berland State University it was decided to equip a new computer room. You were given the task of buying mouses, and you have to spend as little as possible. After all, the country is in crisis! The computers bought for the room were different. Some of them had only USB ports, someΒ β€” only PS/2 ports, and some had both options. You have found a price list of a certain computer shop. In it, for *m* mouses it is specified the cost and the type of the port that is required to plug the mouse in (USB or PS/2). Each mouse from the list can be bought at most once. You want to buy some set of mouses from the given price list in such a way so that you maximize the number of computers equipped with mouses (it is not guaranteed that you will be able to equip all of the computers), and in case of equality of this value you want to minimize the total cost of mouses you will buy.
The first line contains three integers *a*, *b* and *c* (0<=≀<=*a*,<=*b*,<=*c*<=≀<=105) Β β€” the number of computers that only have USB ports, the number of computers, that only have PS/2 ports, and the number of computers, that have both options, respectively. The next line contains one integer *m* (0<=≀<=*m*<=≀<=3Β·105) Β β€” the number of mouses in the price list. The next *m* lines each describe another mouse. The *i*-th line contains first integer *val**i* (1<=≀<=*val**i*<=≀<=109) Β β€” the cost of the *i*-th mouse, then the type of port (USB or PS/2) that is required to plug the mouse in.
Output two integers separated by spaceΒ β€” the number of equipped computers and the total cost of the mouses you will buy.
[ "2 1 1\n4\n5 USB\n6 PS/2\n3 PS/2\n7 PS/2\n" ]
[ "3 14\n" ]
In the first example you can buy the first three mouses. This way you will equip one of the computers that has only a USB port with a USB mouse, and the two PS/2 mouses you will plug into the computer with PS/2 port and the computer with both ports.
[ { "input": "2 1 1\n4\n5 USB\n6 PS/2\n3 PS/2\n7 PS/2", "output": "3 14" }, { "input": "1 4 4\n12\n36949214 USB\n683538043 USB\n595594834 PS/2\n24951774 PS/2\n131512123 USB\n327575645 USB\n30947411 USB\n916758386 PS/2\n474310330 USB\n350512489 USB\n281054887 USB\n875326145 USB", "output": "8 23453...
77
2,867,200
-1
1,110
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 ...
30
5,632,000
0
1,113
155
I_love_\%username\%
[ "brute force" ]
null
null
Vasya adores sport programming. He can't write programs but he loves to watch the contests' progress. Vasya even has a favorite coder and Vasya pays special attention to him. One day Vasya decided to collect the results of all contests where his favorite coder participated and track the progress of his coolness. For each contest where this coder participated, he wrote out a single non-negative number β€” the number of points his favorite coder earned in the contest. Vasya wrote out the points for the contest in the order, in which the contests run (naturally, no two contests ran simultaneously). Vasya considers a coder's performance in a contest amazing in two situations: he can break either his best or his worst performance record. First, it is amazing if during the contest the coder earns strictly more points that he earned on each past contest. Second, it is amazing if during the contest the coder earns strictly less points that he earned on each past contest. A coder's first contest isn't considered amazing. Now he wants to count the number of amazing performances the coder had throughout his whole history of participating in contests. But the list of earned points turned out long and Vasya can't code... That's why he asks you to help him.
The first line contains the single integer *n* (1<=≀<=*n*<=≀<=1000) β€” the number of contests where the coder participated. The next line contains *n* space-separated non-negative integer numbers β€” they are the points which the coder has earned. The points are given in the chronological order. All points do not exceed 10000.
Print the single number β€” the number of amazing performances the coder has had during his whole history of participating in the contests.
[ "5\n100 50 200 150 200\n", "10\n4664 6496 5814 7010 5762 5736 6944 4850 3698 7242\n" ]
[ "2\n", "4\n" ]
In the first sample the performances number 2 and 3 are amazing. In the second sample the performances number 2, 4, 9 and 10 are amazing.
[ { "input": "5\n100 50 200 150 200", "output": "2" }, { "input": "10\n4664 6496 5814 7010 5762 5736 6944 4850 3698 7242", "output": "4" }, { "input": "1\n6", "output": "0" }, { "input": "2\n2 1", "output": "1" }, { "input": "5\n100 36 53 7 81", "output": "2" ...
124
0
3
1,118
142
Help Farmer
[ "brute force", "math" ]
null
null
Once upon a time in the Kingdom of Far Far Away lived Sam the Farmer. Sam had a cow named Dawn and he was deeply attached to her. Sam would spend the whole summer stocking hay to feed Dawn in winter. Sam scythed hay and put it into haystack. As Sam was a bright farmer, he tried to make the process of storing hay simpler and more convenient to use. He collected the hay into cubical hay blocks of the same size. Then he stored the blocks in his barn. After a summer spent in hard toil Sam stored *A*Β·*B*Β·*C* hay blocks and stored them in a barn as a rectangular parallelepiped *A* layers high. Each layer had *B* rows and each row had *C* blocks. At the end of the autumn Sam came into the barn to admire one more time the hay he'd been stacking during this hard summer. Unfortunately, Sam was horrified to see that the hay blocks had been carelessly scattered around the barn. The place was a complete mess. As it turned out, thieves had sneaked into the barn. They completely dissembled and took away a layer of blocks from the parallelepiped's front, back, top and sides. As a result, the barn only had a parallelepiped containing (*A*<=-<=1)<=Γ—<=(*B*<=-<=2)<=Γ—<=(*C*<=-<=2) hay blocks. To hide the evidence of the crime, the thieves had dissembled the parallelepiped into single 1<=Γ—<=1<=Γ—<=1 blocks and scattered them around the barn. After the theft Sam counted *n* hay blocks in the barn but he forgot numbers *A*, *B* ΠΈ *C*. Given number *n*, find the minimally possible and maximally possible number of stolen hay blocks.
The only line contains integer *n* from the problem's statement (1<=≀<=*n*<=≀<=109).
Print space-separated minimum and maximum number of hay blocks that could have been stolen by the thieves. Note that the answer to the problem can be large enough, so you must use the 64-bit integer type for calculations. Please, do not use the %lld specificator to read or write 64-bit integers in Π‘++. It is preferred to use cin, cout streams or the %I64d specificator.
[ "4\n", "7\n", "12\n" ]
[ "28 41\n", "47 65\n", "48 105\n" ]
Let's consider the first sample test. If initially Sam has a parallelepiped consisting of 32 = 2 × 4 × 4 hay blocks in his barn, then after the theft the barn has 4 = (2 - 1) × (4 - 2) × (4 - 2) hay blocks left. Thus, the thieves could have stolen 32 - 4 = 28 hay blocks. If Sam initially had a parallelepiped consisting of 45 = 5 × 3 × 3 hay blocks in his barn, then after the theft the barn has 4 = (5 - 1) × (3 - 2) × (3 - 2) hay blocks left. Thus, the thieves could have stolen 45 - 4 = 41 hay blocks. No other variants of the blocks' initial arrangement (that leave Sam with exactly 4 blocks after the theft) can permit the thieves to steal less than 28 or more than 41 blocks.
[ { "input": "4", "output": "28 41" }, { "input": "7", "output": "47 65" }, { "input": "12", "output": "48 105" }, { "input": "1", "output": "17 17" }, { "input": "6", "output": "34 57" }, { "input": "8", "output": "40 73" }, { "input": "9", ...
1,000
1,228,800
0
1,119
780
Andryusha and Socks
[ "implementation" ]
null
null
Andryusha is an orderly boy and likes to keep things in their place. Today he faced a problem to put his socks in the wardrobe. He has *n* distinct pairs of socks which are initially in a bag. The pairs are numbered from 1 to *n*. Andryusha wants to put paired socks together and put them in the wardrobe. He takes the socks one by one from the bag, and for each sock he looks whether the pair of this sock has been already took out of the bag, or not. If not (that means the pair of this sock is still in the bag), he puts the current socks on the table in front of him. Otherwise, he puts both socks from the pair to the wardrobe. Andryusha remembers the order in which he took the socks from the bag. Can you tell him what is the maximum number of socks that were on the table at the same time?
The first line contains the single integer *n* (1<=≀<=*n*<=≀<=105)Β β€” the number of sock pairs. The second line contains 2*n* integers *x*1,<=*x*2,<=...,<=*x*2*n* (1<=≀<=*x**i*<=≀<=*n*), which describe the order in which Andryusha took the socks from the bag. More precisely, *x**i* means that the *i*-th sock Andryusha took out was from pair *x**i*. It is guaranteed that Andryusha took exactly two socks of each pair.
Print single integerΒ β€” the maximum number of socks that were on the table at the same time.
[ "1\n1 1\n", "3\n2 1 1 3 2 3\n" ]
[ "1\n", "2\n" ]
In the first example Andryusha took a sock from the first pair and put it on the table. Then he took the next sock which is from the first pair as well, so he immediately puts both socks to the wardrobe. Thus, at most one sock was on the table at the same time. In the second example Andryusha behaved as follows: - Initially the table was empty, he took out a sock from pair 2 and put it on the table. - Sock (2) was on the table. Andryusha took out a sock from pair 1 and put it on the table. - Socks (1, 2) were on the table. Andryusha took out a sock from pair 1, and put this pair into the wardrobe. - Sock (2) was on the table. Andryusha took out a sock from pair 3 and put it on the table. - Socks (2, 3) were on the table. Andryusha took out a sock from pair 2, and put this pair into the wardrobe. - Sock (3) was on the table. Andryusha took out a sock from pair 3 and put this pair into the wardrobe.
[ { "input": "1\n1 1", "output": "1" }, { "input": "3\n2 1 1 3 2 3", "output": "2" }, { "input": "5\n5 1 3 2 4 3 1 2 4 5", "output": "5" }, { "input": "10\n4 2 6 3 4 8 7 1 1 5 2 10 6 8 3 5 10 9 9 7", "output": "6" }, { "input": "50\n30 47 31 38 37 50 36 43 9 23 2 2 ...
202
13,721,600
3
1,121
551
GukiZ hates Boxes
[ "binary search", "greedy" ]
null
null
Professor GukiZ is concerned about making his way to school, because massive piles of boxes are blocking his way. In total there are *n* piles of boxes, arranged in a line, from left to right, *i*-th pile (1<=≀<=*i*<=≀<=*n*) containing *a**i* boxes. Luckily, *m* students are willing to help GukiZ by removing all the boxes from his way. Students are working simultaneously. At time 0, all students are located left of the first pile. It takes one second for every student to move from this position to the first pile, and after that, every student must start performing sequence of two possible operations, each taking one second to complete. Possible operations are: 1. If *i*<=β‰ <=*n*, move from pile *i* to pile *i*<=+<=1;1. If pile located at the position of student is not empty, remove one box from it. GukiZ's students aren't smart at all, so they need you to tell them how to remove boxes before professor comes (he is very impatient man, and doesn't want to wait). They ask you to calculate minumum time *t* in seconds for which they can remove all the boxes from GukiZ's way. Note that students can be positioned in any manner after *t* seconds, but all the boxes must be removed.
The first line contains two integers *n* and *m* (1<=≀<=*n*,<=*m*<=≀<=105), the number of piles of boxes and the number of GukiZ's students. The second line contains *n* integers *a*1,<=*a*2,<=... *a**n* (0<=≀<=*a**i*<=≀<=109) where *a**i* represents the number of boxes on *i*-th pile. It's guaranteed that at least one pile of is non-empty.
In a single line, print one number, minimum time needed to remove all the boxes in seconds.
[ "2 1\n1 1\n", "3 2\n1 0 2\n", "4 100\n3 4 5 4\n" ]
[ "4\n", "5\n", "5\n" ]
First sample: Student will first move to the first pile (1 second), then remove box from first pile (1 second), then move to the second pile (1 second) and finally remove the box from second pile (1 second). Second sample: One of optimal solutions is to send one student to remove a box from the first pile and a box from the third pile, and send another student to remove a box from the third pile. Overall, 5 seconds. Third sample: With a lot of available students, send three of them to remove boxes from the first pile, four of them to remove boxes from the second pile, five of them to remove boxes from the third pile, and four of them to remove boxes from the fourth pile. Process will be over in 5 seconds, when removing the boxes from the last pile is finished.
[ { "input": "2 1\n1 1", "output": "4" }, { "input": "3 2\n1 0 2", "output": "5" }, { "input": "4 100\n3 4 5 4", "output": "5" }, { "input": "5 8\n121351 0 13513 0 165454", "output": "37544" }, { "input": "6 6\n0 10 0 0 10 0", "output": "8" }, { "input":...
140
13,516,800
0
1,124
1,000
Covered Points Count
[ "data structures", "implementation", "sortings" ]
null
null
You are given $n$ segments on a coordinate line; each endpoint of every segment has integer coordinates. Some segments can degenerate to points. Segments can intersect with each other, be nested in each other or even coincide. Your task is the following: for every $k \in [1..n]$, calculate the number of points with integer coordinates such that the number of segments that cover these points equals $k$. A segment with endpoints $l_i$ and $r_i$ covers point $x$ if and only if $l_i \le x \le r_i$.
The first line of the input contains one integer $n$ ($1 \le n \le 2 \cdot 10^5$) β€” the number of segments. The next $n$ lines contain segments. The $i$-th line contains a pair of integers $l_i, r_i$ ($0 \le l_i \le r_i \le 10^{18}$) β€” the endpoints of the $i$-th segment.
Print $n$ space separated integers $cnt_1, cnt_2, \dots, cnt_n$, where $cnt_i$ is equal to the number of points such that the number of segments that cover these points equals to $i$.
[ "3\n0 3\n1 3\n3 8\n", "3\n1 3\n2 4\n5 7\n" ]
[ "6 2 1 \n", "5 2 0 \n" ]
The picture describing the first example: <img class="tex-graphics" src="https://espresso.codeforces.com/f76b3fe547bff6be5b14de76c8b78ba3efecc744.png" style="max-width: 100.0%;max-height: 100.0%;"/> Points with coordinates $[0, 4, 5, 6, 7, 8]$ are covered by one segment, points $[1, 2]$ are covered by two segments and point $[3]$ is covered by three segments. The picture describing the second example: <img class="tex-graphics" src="https://espresso.codeforces.com/6e9332c303e1bc5d6cf34c2d6c5e2a19c9417289.png" style="max-width: 100.0%;max-height: 100.0%;"/> Points $[1, 4, 5, 6, 7]$ are covered by one segment, points $[2, 3]$ are covered by two segments and there are no points covered by three segments.
[ { "input": "3\n0 3\n1 3\n3 8", "output": "6 2 1 " }, { "input": "3\n1 3\n2 4\n5 7", "output": "5 2 0 " }, { "input": "1\n0 1000000000000000000", "output": "1000000000000000001 " } ]
3,000
156,672,000
0
1,126
869
The Artful Expedient
[ "brute force", "implementation" ]
null
null
Rock... Paper! After Karen have found the deterministic winning (losing?) strategy for rock-paper-scissors, her brother, Koyomi, comes up with a new game as a substitute. The game works as follows. A positive integer *n* is decided first. Both Koyomi and Karen independently choose *n* distinct positive integers, denoted by *x*1,<=*x*2,<=...,<=*x**n* and *y*1,<=*y*2,<=...,<=*y**n* respectively. They reveal their sequences, and repeat until all of 2*n* integers become distinct, which is the only final state to be kept and considered. Then they count the number of ordered pairs (*i*,<=*j*) (1<=≀<=*i*,<=*j*<=≀<=*n*) such that the value *x**i* xor *y**j* equals to one of the 2*n* integers. Here xor means the [bitwise exclusive or](https://en.wikipedia.org/wiki/Bitwise_operation#XOR) operation on two integers, and is denoted by operators ^ and/or xor in most programming languages. Karen claims a win if the number of such pairs is even, and Koyomi does otherwise. And you're here to help determine the winner of their latest game.
The first line of input contains a positive integer *n* (1<=≀<=*n*<=≀<=2<=000) β€” the length of both sequences. The second line contains *n* space-separated integers *x*1,<=*x*2,<=...,<=*x**n* (1<=≀<=*x**i*<=≀<=2Β·106) β€” the integers finally chosen by Koyomi. The third line contains *n* space-separated integers *y*1,<=*y*2,<=...,<=*y**n* (1<=≀<=*y**i*<=≀<=2Β·106) β€” the integers finally chosen by Karen. Input guarantees that the given 2*n* integers are pairwise distinct, that is, no pair (*i*,<=*j*) (1<=≀<=*i*,<=*j*<=≀<=*n*) exists such that one of the following holds: *x**i*<==<=*y**j*; *i*<=β‰ <=*j* and *x**i*<==<=*x**j*; *i*<=β‰ <=*j* and *y**i*<==<=*y**j*.
Output one line β€” the name of the winner, that is, "Koyomi" or "Karen" (without quotes). Please be aware of the capitalization.
[ "3\n1 2 3\n4 5 6\n", "5\n2 4 6 8 10\n9 7 5 3 1\n" ]
[ "Karen\n", "Karen\n" ]
In the first example, there are 6 pairs satisfying the constraint: (1, 1), (1, 2), (2, 1), (2, 3), (3, 2) and (3, 3). Thus, Karen wins since 6 is an even number. In the second example, there are 16 such pairs, and Karen wins again.
[ { "input": "3\n1 2 3\n4 5 6", "output": "Karen" }, { "input": "5\n2 4 6 8 10\n9 7 5 3 1", "output": "Karen" }, { "input": "1\n1\n2000000", "output": "Karen" }, { "input": "2\n97153 2000000\n1999998 254", "output": "Karen" }, { "input": "15\n31 30 29 28 27 26 25 24...
1,000
614,400
0
1,131
766
Mahmoud and a Triangle
[ "constructive algorithms", "geometry", "greedy", "math", "number theory", "sortings" ]
null
null
Mahmoud has *n* line segments, the *i*-th of them has length *a**i*. Ehab challenged him to use exactly 3 line segments to form a non-degenerate triangle. Mahmoud doesn't accept challenges unless he is sure he can win, so he asked you to tell him if he should accept the challenge. Given the lengths of the line segments, check if he can choose exactly 3 of them to form a non-degenerate triangle. Mahmoud should use exactly 3 line segments, he can't concatenate two line segments or change any length. A non-degenerate triangle is a triangle with positive area.
The first line contains single integer *n* (3<=≀<=*n*<=≀<=105)Β β€” the number of line segments Mahmoud has. The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≀<=*a**i*<=≀<=109)Β β€” the lengths of line segments Mahmoud has.
In the only line print "YES" if he can choose exactly three line segments and form a non-degenerate triangle with them, and "NO" otherwise.
[ "5\n1 5 3 2 4\n", "3\n4 1 2\n" ]
[ "YES\n", "NO\n" ]
For the first example, he can use line segments with lengths 2, 4 and 5 to form a non-degenerate triangle.
[ { "input": "5\n1 5 3 2 4", "output": "YES" }, { "input": "3\n4 1 2", "output": "NO" }, { "input": "30\n197 75 517 39724 7906061 1153471 3 15166 168284 3019844 272293 316 16 24548 42 118 5792 5 9373 1866366 4886214 24 2206 712886 104005 1363 836 64273 440585 3576", "output": "NO" },...
93
7,884,800
0
1,133
580
Kefa and First Steps
[ "brute force", "dp", "implementation" ]
null
null
Kefa decided to make some money doing business on the Internet for exactly *n* days. He knows that on the *i*-th day (1<=≀<=*i*<=≀<=*n*) he makes *a**i* money. Kefa loves progress, that's why he wants to know the length of the maximum non-decreasing subsegment in sequence *a**i*. Let us remind you that the subsegment of the sequence is its continuous fragment. A subsegment of numbers is called non-decreasing if all numbers in it follow in the non-decreasing order. Help Kefa cope with this task!
The first line contains integer *n* (1<=≀<=*n*<=≀<=105). The second line contains *n* integers *a*1,<=<=*a*2,<=<=...,<=<=*a**n* (1<=≀<=*a**i*<=≀<=109).
Print a single integer β€” the length of the maximum non-decreasing subsegment of sequence *a*.
[ "6\n2 2 1 3 4 1\n", "3\n2 2 9\n" ]
[ "3", "3" ]
In the first test the maximum non-decreasing subsegment is the numbers from the third to the fifth one. In the second test the maximum non-decreasing subsegment is the numbers from the first to the third one.
[ { "input": "6\n2 2 1 3 4 1", "output": "3" }, { "input": "3\n2 2 9", "output": "3" }, { "input": "5\n10 100 111 1 2", "output": "3" }, { "input": "10\n1 2 3 4 1 2 3 4 5 6", "output": "6" }, { "input": "50\n1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ...
61
2,764,800
-1
1,136
907
Tic-Tac-Toe
[ "implementation" ]
null
null
Two bears are playing tic-tac-toe via mail. It's boring for them to play usual tic-tac-toe game, so they are a playing modified version of this game. Here are its rules. The game is played on the following field. Players are making moves by turns. At first move a player can put his chip in any cell of any small field. For following moves, there are some restrictions: if during last move the opposite player put his chip to cell with coordinates (*x**l*,<=*y**l*) in some small field, the next move should be done in one of the cells of the small field with coordinates (*x**l*,<=*y**l*). For example, if in the first move a player puts his chip to lower left cell of central field, then the second player on his next move should put his chip into some cell of lower left field (pay attention to the first test case). If there are no free cells in the required field, the player can put his chip to any empty cell on any field. You are given current state of the game and coordinates of cell in which the last move was done. You should find all cells in which the current player can put his chip. A hare works as a postman in the forest, he likes to foul bears. Sometimes he changes the game field a bit, so the current state of the game could be unreachable. However, after his changes the cell where the last move was done is not empty. You don't need to find if the state is unreachable or not, just output possible next moves according to the rules.
First 11 lines contains descriptions of table with 9 rows and 9 columns which are divided into 9 small fields by spaces and empty lines. Each small field is described by 9 characters without spaces and empty lines. character "x" (ASCII-code 120) means that the cell is occupied with chip of the first player, character "o" (ASCII-code 111) denotes a field occupied with chip of the second player, character "." (ASCII-code 46) describes empty cell. The line after the table contains two integers *x* and *y* (1<=≀<=*x*,<=*y*<=≀<=9). They describe coordinates of the cell in table where the last move was done. Rows in the table are numbered from up to down and columns are numbered from left to right. It's guaranteed that cell where the last move was done is filled with "x" or "o". Also, it's guaranteed that there is at least one empty cell. It's not guaranteed that current state of game is reachable.
Output the field in same format with characters "!" (ASCII-code 33) on positions where the current player can put his chip. All other cells should not be modified.
[ "... ... ...\n... ... ...\n... ... ...\n\n... ... ...\n... ... ...\n... x.. ...\n\n... ... ...\n... ... ...\n... ... ...\n6 4\n", "xoo x.. x..\nooo ... ...\nooo ... ...\n\nx.. x.. x..\n... ... ...\n... ... ...\n\nx.. x.. x..\n... ... ...\n... ... ...\n7 4\n", "o.. ... ...\n... ... ...\n... ... ...\n\n... xxx .....
[ "... ... ... \n... ... ... \n... ... ... \n\n... ... ... \n... ... ... \n... x.. ... \n\n!!! ... ... \n!!! ... ... \n!!! ... ... \n\n", "xoo x!! x!! \nooo !!! !!! \nooo !!! !!! \n\nx!! x!! x!! \n!!! !!! !!! \n!!! !!! !!! \n\nx!! x!! x!! \n!!! !!! !!! \n!!! !!! !!! \n\n", "o!! !!! !!! \n!!! !!! !!! \n!!! !!! !!!...
In the first test case the first player made a move to lower left cell of central field, so the second player can put a chip only to cells of lower left field. In the second test case the last move was done to upper left cell of lower central field, however all cells in upper left field are occupied, so the second player can put his chip to any empty cell. In the third test case the last move was done to central cell of central field, so current player can put his chip to any cell of central field, which is already occupied, so he can move anywhere. Pay attention that this state of the game is unreachable.
[ { "input": "... ... ...\n... ... ...\n... ... ...\n\n... ... ...\n... ... ...\n... x.. ...\n\n... ... ...\n... ... ...\n... ... ...\n6 4", "output": "... ... ... \n... ... ... \n... ... ... \n\n... ... ... \n... ... ... \n... x.. ... \n\n!!! ... ... \n!!! ... ... \n!!! ... ... " }, { "input": "xoo x...
62
5,632,000
3
1,138
137
Permutation
[ "greedy" ]
null
null
"Hey, it's homework time" β€” 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 β€” 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"...
124
512,000
3
1,140
618
Slime Combining
[ "implementation" ]
null
null
Your friend recently gave you some slimes for your birthday. You have *n* slimes all initially with value 1. You are going to play a game with these slimes. Initially, you put a single slime by itself in a row. Then, you will add the other *n*<=-<=1 slimes one by one. When you add a slime, you place it at the right of all already placed slimes. Then, while the last two slimes in the row have the same value *v*, you combine them together to create a slime with value *v*<=+<=1. You would like to see what the final state of the row is after you've added all *n* slimes. Please print the values of the slimes in the row from left to right.
The first line of the input will contain a single integer, *n* (1<=≀<=*n*<=≀<=100<=000).
Output a single line with *k* integers, where *k* is the number of slimes in the row after you've finished the procedure described in the problem statement. The *i*-th of these numbers should be the value of the *i*-th slime from the left.
[ "1\n", "2\n", "3\n", "8\n" ]
[ "1\n", "2\n", "2 1\n", "4\n" ]
In the first sample, we only have a single slime with value 1. The final state of the board is just a single slime with value 1. In the second sample, we perform the following steps: Initially we place a single slime in a row by itself. Thus, row is initially 1. Then, we will add another slime. The row is now 1 1. Since two rightmost slimes have the same values, we should replace these slimes with one with value 2. Thus, the final state of the board is 2. In the third sample, after adding the first two slimes, our row is 2. After adding one more slime, the row becomes 2 1. In the last sample, the steps look as follows: 1. 1 1. 2 1. 2 1 1. 3 1. 3 1 1. 3 2 1. 3 2 1 1. 4
[ { "input": "1", "output": "1" }, { "input": "2", "output": "2" }, { "input": "3", "output": "2 1" }, { "input": "8", "output": "4" }, { "input": "100000", "output": "17 16 11 10 8 6" }, { "input": "12345", "output": "14 13 6 5 4 1" }, { "in...
46
6,963,200
0
1,142
978
Petya's Exams
[ "greedy", "implementation", "sortings" ]
null
null
Petya studies at university. The current academic year finishes with $n$ special days. Petya needs to pass $m$ exams in those special days. The special days in this problem are numbered from $1$ to $n$. There are three values about each exam: - $s_i$ β€” the day, when questions for the $i$-th exam will be published, - $d_i$ β€” the day of the $i$-th exam ($s_i &lt; d_i$), - $c_i$ β€” number of days Petya needs to prepare for the $i$-th exam. For the $i$-th exam Petya should prepare in days between $s_i$ and $d_i-1$, inclusive. There are three types of activities for Petya in each day: to spend a day doing nothing (taking a rest), to spend a day passing exactly one exam or to spend a day preparing for exactly one exam. So he can't pass/prepare for multiple exams in a day. He can't mix his activities in a day. If he is preparing for the $i$-th exam in day $j$, then $s_i \le j &lt; d_i$. It is allowed to have breaks in a preparation to an exam and to alternate preparations for different exams in consecutive days. So preparation for an exam is not required to be done in consecutive days. Find the schedule for Petya to prepare for all exams and pass them, or report that it is impossible.
The first line contains two integers $n$ and $m$ $(2 \le n \le 100, 1 \le m \le n)$ β€” the number of days and the number of exams. Each of the following $m$ lines contains three integers $s_i$, $d_i$, $c_i$ $(1 \le s_i &lt; d_i \le n, 1 \le c_i \le n)$ β€” the day, when questions for the $i$-th exam will be given, the day of the $i$-th exam, number of days Petya needs to prepare for the $i$-th exam. Guaranteed, that all the exams will be in different days. Questions for different exams can be given in the same day. It is possible that, in the day of some exam, the questions for other exams are given.
If Petya can not prepare and pass all the exams, print -1. In case of positive answer, print $n$ integers, where the $j$-th number is: - $(m + 1)$, if the $j$-th day is a day of some exam (recall that in each day no more than one exam is conducted), - zero, if in the $j$-th day Petya will have a rest, - $i$ ($1 \le i \le m$), if Petya will prepare for the $i$-th exam in the day $j$ (the total number of days Petya prepares for each exam should be strictly equal to the number of days needed to prepare for it).Assume that the exams are numbered in order of appearing in the input, starting from $1$.If there are multiple schedules, print any of them.
[ "5 2\n1 3 1\n1 5 1\n", "3 2\n1 3 1\n1 2 1\n", "10 3\n4 7 2\n1 10 3\n8 9 1\n" ]
[ "1 2 3 0 3 \n", "-1\n", "2 2 2 1 1 0 4 3 4 4 \n" ]
In the first example Petya can, for example, prepare for exam $1$ in the first day, prepare for exam $2$ in the second day, pass exam $1$ in the third day, relax in the fourth day, and pass exam $2$ in the fifth day. So, he can prepare and pass all exams. In the second example, there are three days and two exams. So, Petya can prepare in only one day (because in two other days he should pass exams). Then Petya can not prepare and pass all exams.
[ { "input": "5 2\n1 3 1\n1 5 1", "output": "1 2 3 0 3 " }, { "input": "3 2\n1 3 1\n1 2 1", "output": "-1" }, { "input": "10 3\n4 7 2\n1 10 3\n8 9 1", "output": "2 2 2 1 1 0 4 3 4 4 " }, { "input": "2 1\n1 2 1", "output": "1 2 " }, { "input": "3 1\n1 2 2", "outp...
15
0
0
1,144
713
Sonya and Problem Wihtout a Legend
[ "dp", "sortings" ]
null
null
Sonya was unable to think of a story for this problem, so here comes the formal description. You are given the array containing *n* positive integers. At one turn you can pick any element and increase or decrease it by 1. The goal is the make the array strictly increasing by making the minimum possible number of operations. You are allowed to change elements in any way, they can become negative or equal to 0.
The first line of the input contains a single integer *n* (1<=≀<=*n*<=≀<=3000)Β β€” the length of the array. Next line contains *n* integer *a**i* (1<=≀<=*a**i*<=≀<=109).
Print the minimum number of operation required to make the array strictly increasing.
[ "7\n2 1 5 11 5 9 11\n", "5\n5 4 3 2 1\n" ]
[ "9\n", "12\n" ]
In the first sample, the array is going to look as follows: 2 3 5 6 7 9 11 |2 - 2| + |1 - 3| + |5 - 5| + |11 - 6| + |5 - 7| + |9 - 9| + |11 - 11| = 9 And for the second sample: 1 2 3 4 5 |5 - 1| + |4 - 2| + |3 - 3| + |2 - 4| + |1 - 5| = 12
[ { "input": "7\n2 1 5 11 5 9 11", "output": "9" }, { "input": "5\n5 4 3 2 1", "output": "12" }, { "input": "2\n1 1000", "output": "0" }, { "input": "2\n1000 1", "output": "1000" }, { "input": "5\n100 80 60 70 90", "output": "54" }, { "input": "10\n10 16...
249
11,366,400
3
1,146
276
Little Girl and Game
[ "games", "greedy" ]
null
null
The Little Girl loves problems on games very much. Here's one of them. Two players have got a string *s*, consisting of lowercase English letters. They play a game that is described by the following rules: - The players move in turns; In one move the player can remove an arbitrary letter from string *s*. - If the player before his turn can reorder the letters in string *s* so as to get a palindrome, this player wins. A palindrome is a string that reads the same both ways (from left to right, and vice versa). For example, string "abba" is a palindrome and string "abc" isn't. Determine which player will win, provided that both sides play optimally well β€” the one who moves first or the one who moves second.
The input contains a single line, containing string *s* (1<=≀<=|*s*|<=<=≀<=<=103). String *s* consists of lowercase English letters.
In a single line print word "First" if the first player wins (provided that both players play optimally well). Otherwise, print word "Second". Print the words without the quotes.
[ "aba\n", "abca\n" ]
[ "First\n", "Second\n" ]
none
[ { "input": "aba", "output": "First" }, { "input": "abca", "output": "Second" }, { "input": "aabb", "output": "First" }, { "input": "ctjxzuimsxnarlciuynqeoqmmbqtagszuo", "output": "Second" }, { "input": "gevqgtaorjixsxnbcoybr", "output": "First" }, { "i...
62
0
0
1,147