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Batch Sort
[ "brute force", "greedy", "implementation", "math" ]
null
null
You are given a table consisting of *n* rows and *m* columns. Numbers in each row form a permutation of integers from 1 to *m*. You are allowed to pick two elements in one row and swap them, but no more than once for each row. Also, no more than once you are allowed to pick two columns and swap them. Thus, you are al...
The first line of the input contains two integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=20) — the number of rows and the number of columns in the given table. Each of next *n* lines contains *m* integers — elements of the table. It's guaranteed that numbers in each line form a permutation of integers from 1 to *m*.
If there is a way to obtain the identity permutation in each row by following the given rules, print "YES" (without quotes) in the only line of the output. Otherwise, print "NO" (without quotes).
[ "2 4\n1 3 2 4\n1 3 4 2\n", "4 4\n1 2 3 4\n2 3 4 1\n3 4 1 2\n4 1 2 3\n", "3 6\n2 1 3 4 5 6\n1 2 4 3 5 6\n1 2 3 4 6 5\n" ]
[ "YES\n", "NO\n", "YES\n" ]
In the first sample, one can act in the following way: 1. Swap second and third columns. Now the table is <center class="tex-equation">1 2 3 4</center> <center class="tex-equation">1 4 3 2</center> 1. In the second row, swap the second and the fourth elements. Now the table is <center class="tex-equation">1 2 3 4</...
[ { "input": "2 4\n1 3 2 4\n1 3 4 2", "output": "YES" }, { "input": "4 4\n1 2 3 4\n2 3 4 1\n3 4 1 2\n4 1 2 3", "output": "NO" }, { "input": "3 6\n2 1 3 4 5 6\n1 2 4 3 5 6\n1 2 3 4 6 5", "output": "YES" }, { "input": "3 10\n1 2 3 4 5 6 7 10 9 8\n5 2 3 4 1 6 7 8 9 10\n1 2 3 4 5 6...
62
1,331,200
0
2,757
991
Bishwock
[ "dp", "greedy" ]
null
null
Bishwock is a chess figure that consists of three squares resembling an "L-bar". This figure can be rotated by 90, 180 and 270 degrees so it can have four possible states: Bishwocks don't attack any squares and can even occupy on the adjacent squares as long as they don't occupy the same square. Vasya has a board wi...
The input contains two nonempty strings that describe Vasya's board. Those strings contain only symbols "0" (zero) that denote the empty squares and symbols "X" (uppercase English letter) that denote the squares occupied by pawns. Strings are nonempty and are of the same length that does not exceed $100$.
Output a single integer — the maximum amount of bishwocks that can be placed onto the given board.
[ "00\n00\n", "00X00X0XXX0\n0XXX0X00X00\n", "0X0X0\n0X0X0\n", "0XXX0\n00000\n" ]
[ "1", "4", "0", "2" ]
none
[ { "input": "00\n00", "output": "1" }, { "input": "00X00X0XXX0\n0XXX0X00X00", "output": "4" }, { "input": "0X0X0\n0X0X0", "output": "0" }, { "input": "0XXX0\n00000", "output": "2" }, { "input": "0\n0", "output": "0" }, { "input": "0\nX", "output": "...
62
0
0
2,761
48
Ivan the Fool VS Gorynych the Dragon
[ "dp", "games", "graphs" ]
E. Ivan the Fool VS Gorynych the Dragon
2
256
Once upon a time in a kingdom far, far away… Okay, let’s start at the point where Ivan the Fool met Gorynych the Dragon. Ivan took out his magic sword and the battle began. First Gorynych had *h* heads and *t* tails. With each strike of the sword Ivan can either cut off several heads (from 1 to *n*, but not more than G...
The first line contains three integers *h*, *t* and *R* (0<=≤<=*h*,<=*t*,<=*R*<=≤<=200, 0<=&lt;<=*h*<=+<=*t*<=≤<=*R*) which represent the initial numbers of Gorynych’s heads and tails and the largest total number of heads and tails with which Gorynych the Dragon does not yet attack. The next line contains integer *n* (...
Print "Ivan" (without quotes) in the first line if Ivan wins, or "Zmey" (that means a dragon in Russian) if Gorynych the Dragon wins. In the second line print a single integer which represents the number of blows Ivan makes. If the battle will continue forever, print in the first line "Draw".
[ "2 2 4\n2\n1 0\n0 1\n3\n0 1\n0 1\n0 0\n", "2 2 4\n1\n0 1\n1\n1 0\n", "2 2 5\n1\n1 1\n1\n3 0\n" ]
[ "Ivan\n2\n", "Draw\n", "Zmey\n2\n" ]
none
[]
92
0
0
2,773
901
Hashing Trees
[ "constructive algorithms", "trees" ]
null
null
Sasha is taking part in a programming competition. In one of the problems she should check if some rooted trees are isomorphic or not. She has never seen this problem before, but, being an experienced participant, she guessed that she should match trees to some sequences and then compare these sequences instead of tree...
The first line contains a single integer *h* (2<=≤<=*h*<=≤<=105) — the height of the tree. The second line contains *h*<=+<=1 integers — the sequence *a*0,<=*a*1,<=...,<=*a**h* (1<=≤<=*a**i*<=≤<=2·105). The sum of all *a**i* does not exceed 2·105. It is guaranteed that there is at least one tree matching this sequence...
If there is only one tree matching this sequence, print "perfect". Otherwise print "ambiguous" in the first line. In the second and in the third line print descriptions of two trees in the following format: in one line print integers, the *k*-th of them should be the parent of vertex *k* or be equal to zero, if the *...
[ "2\n1 1 1\n", "2\n1 2 2\n" ]
[ "perfect\n", "ambiguous\n0 1 1 3 3\n0 1 1 3 2\n" ]
The only tree in the first example and the two printed trees from the second example are shown on the picture: <img class="tex-graphics" src="https://espresso.codeforces.com/ae5d1889e09854f9d8ad6e29ab7afbe690ca4702.png" style="max-width: 100.0%;max-height: 100.0%;"/>
[ { "input": "2\n1 1 1", "output": "perfect" }, { "input": "2\n1 2 2", "output": "ambiguous\n0 1 1 3 3\n0 1 1 3 2" }, { "input": "10\n1 1 1 1 1 1 1 1 1 1 1", "output": "perfect" }, { "input": "10\n1 1 1 1 1 2 1 1 1 1 1", "output": "perfect" }, { "input": "10\n1 1 1 ...
139
0
0
2,775
0
none
[ "none" ]
null
null
You are given a rebus of form ? + ? - ? + ? = n, consisting of only question marks, separated by arithmetic operation '+' and '-', equality and positive integer *n*. The goal is to replace each question mark with some positive integer from 1 to *n*, such that equality holds.
The only line of the input contains a rebus. It's guaranteed that it contains no more than 100 question marks, integer *n* is positive and doesn't exceed 1<=000<=000, all letters and integers are separated by spaces, arithmetic operations are located only between question marks.
The first line of the output should contain "Possible" (without quotes) if rebus has a solution and "Impossible" (without quotes) otherwise. If the answer exists, the second line should contain any valid rebus with question marks replaced by integers from 1 to *n*. Follow the format given in the samples.
[ "? + ? - ? + ? + ? = 42\n", "? - ? = 1\n", "? = 1000000\n" ]
[ "Possible\n9 + 13 - 39 + 28 + 31 = 42\n", "Impossible\n", "Possible\n1000000 = 1000000\n" ]
none
[ { "input": "? + ? - ? + ? + ? = 42", "output": "Possible\n1 + 1 - 1 + 1 + 40 = 42" }, { "input": "? - ? = 1", "output": "Impossible" }, { "input": "? = 1000000", "output": "Possible\n1000000 = 1000000" }, { "input": "? + ? + ? + ? + ? + ? + ? + ? + ? + ? + ? + ? + ? + ? + ? +...
124
0
3
2,782
525
Ilya and Sticks
[ "greedy", "math", "sortings" ]
null
null
In the evening, after the contest Ilya was bored, and he really felt like maximizing. He remembered that he had a set of *n* sticks and an instrument. Each stick is characterized by its length *l**i*. Ilya decided to make a rectangle from the sticks. And due to his whim, he decided to make rectangles in such a way tha...
The first line of the input contains a positive integer *n* (1<=≤<=*n*<=≤<=105) — the number of the available sticks. The second line of the input contains *n* positive integers *l**i* (2<=≤<=*l**i*<=≤<=106) — the lengths of the sticks.
The first line of the output must contain a single non-negative integer — the maximum total area of the rectangles that Ilya can make from the available sticks.
[ "4\n2 4 4 2\n", "4\n2 2 3 5\n", "4\n100003 100004 100005 100006\n" ]
[ "8\n", "0\n", "10000800015\n" ]
none
[ { "input": "4\n2 4 4 2", "output": "8" }, { "input": "4\n2 2 3 5", "output": "0" }, { "input": "4\n100003 100004 100005 100006", "output": "10000800015" }, { "input": "8\n5 3 3 3 3 4 4 4", "output": "25" }, { "input": "10\n123 124 123 124 2 2 2 2 9 9", "output...
140
7,577,600
0
2,784
75
Modified GCD
[ "binary search", "number theory" ]
C. Modified GCD
2
256
Well, here is another math class task. In mathematics, GCD is the greatest common divisor, and it's an easy task to calculate the GCD between two positive integers. A common divisor for two positive numbers is a number which both numbers are divisible by. But your teacher wants to give you a harder task, in this task...
The first line contains two integers *a* and *b*, the two integers as described above (1<=≤<=*a*,<=*b*<=≤<=109). The second line contains one integer *n*, the number of queries (1<=≤<=*n*<=≤<=104). Then *n* lines follow, each line contains one query consisting of two integers, *low* and *high* (1<=≤<=*low*<=≤<=*high*<=...
Print *n* lines. The *i*-th of them should contain the result of the *i*-th query in the input. If there is no common divisor in the given range for any query, you should print -1 as a result for this query.
[ "9 27\n3\n1 5\n10 11\n9 11\n" ]
[ "3\n-1\n9\n" ]
none
[ { "input": "9 27\n3\n1 5\n10 11\n9 11", "output": "3\n-1\n9" }, { "input": "48 72\n2\n8 29\n29 37", "output": "24\n-1" }, { "input": "90 100\n10\n51 61\n6 72\n1 84\n33 63\n37 69\n18 21\n9 54\n49 90\n14 87\n37 90", "output": "-1\n10\n10\n-1\n-1\n-1\n10\n-1\n-1\n-1" }, { "input...
280
0
0
2,791
572
Arrays
[ "sortings" ]
null
null
You are given two arrays *A* and *B* consisting of integers, sorted in non-decreasing order. Check whether it is possible to choose *k* numbers in array *A* and choose *m* numbers in array *B* so that any number chosen in the first array is strictly less than any number chosen in the second array.
The first line contains two integers *n**A*,<=*n**B* (1<=≤<=*n**A*,<=*n**B*<=≤<=105), separated by a space — the sizes of arrays *A* and *B*, correspondingly. The second line contains two integers *k* and *m* (1<=≤<=*k*<=≤<=*n**A*,<=1<=≤<=*m*<=≤<=*n**B*), separated by a space. The third line contains *n**A* numbers *...
Print "YES" (without the quotes), if you can choose *k* numbers in array *A* and *m* numbers in array *B* so that any number chosen in array *A* was strictly less than any number chosen in array *B*. Otherwise, print "NO" (without the quotes).
[ "3 3\n2 1\n1 2 3\n3 4 5\n", "3 3\n3 3\n1 2 3\n3 4 5\n", "5 2\n3 1\n1 1 1 1 1\n2 2\n" ]
[ "YES\n", "NO\n", "YES\n" ]
In the first sample test you can, for example, choose numbers 1 and 2 from array *A* and number 3 from array *B* (1 &lt; 3 and 2 &lt; 3). In the second sample test the only way to choose *k* elements in the first array and *m* elements in the second one is to choose all numbers in both arrays, but then not all the num...
[ { "input": "3 3\n2 1\n1 2 3\n3 4 5", "output": "YES" }, { "input": "3 3\n3 3\n1 2 3\n3 4 5", "output": "NO" }, { "input": "5 2\n3 1\n1 1 1 1 1\n2 2", "output": "YES" }, { "input": "3 5\n1 1\n5 5 5\n5 5 5 5 5", "output": "NO" }, { "input": "1 1\n1 1\n1\n1", "ou...
62
0
0
2,795
804
Minimum number of steps
[ "combinatorics", "greedy", "implementation", "math" ]
null
null
We have a string of letters 'a' and 'b'. We want to perform some operations on it. On each step we choose one of substrings "ab" in the string and replace it with the string "bba". If we have no "ab" as a substring, our job is done. Print the minimum number of steps we should perform to make our job done modulo 109<=+<...
The first line contains the initial string consisting of letters 'a' and 'b' only with length from 1 to 106.
Print the minimum number of steps modulo 109<=+<=7.
[ "ab\n", "aab\n" ]
[ "1\n", "3\n" ]
The first example: "ab"  →  "bba". The second example: "aab"  →  "abba"  →  "bbaba"  →  "bbbbaa".
[ { "input": "ab", "output": "1" }, { "input": "aab", "output": "3" }, { "input": "aaaaabaabababaaaaaba", "output": "17307" }, { "input": "abaabaaabbabaabab", "output": "1795" }, { "input": "abbaa", "output": "2" }, { "input": "abbaaabaabaaaaabbbbaababaa...
30
0
0
2,796
0
none
[ "none" ]
null
null
There is a rectangular grid of *n* rows of *m* initially-white cells each. Arkady performed a certain number (possibly zero) of operations on it. In the *i*-th operation, a non-empty subset of rows *R**i* and a non-empty subset of columns *C**i* are chosen. For each row *r* in *R**i* and each column *c* in *C**i*, the...
The first line contains two space-separated integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=50) — the number of rows and columns of the grid, respectively. Each of the following *n* lines contains a string of *m* characters, each being either '.' (denoting a white cell) or '#' (denoting a black cell), representing the desir...
If the given grid can be achieved by any valid sequence of operations, output "Yes"; otherwise output "No" (both without quotes). You can print each character in any case (upper or lower).
[ "5 8\n.#.#..#.\n.....#..\n.#.#..#.\n#.#....#\n.....#..\n", "5 5\n..#..\n..#..\n#####\n..#..\n..#..\n", "5 9\n........#\n#........\n..##.#...\n.......#.\n....#.#.#\n" ]
[ "Yes\n", "No\n", "No\n" ]
For the first example, the desired setup can be produced by 3 operations, as is shown below. For the second example, the desired setup cannot be produced, since in order to colour the center row, the third row and all columns must be selected in one operation, but after that no column can be selected again, hence it w...
[ { "input": "5 8\n.#.#..#.\n.....#..\n.#.#..#.\n#.#....#\n.....#..", "output": "Yes" }, { "input": "5 5\n..#..\n..#..\n#####\n..#..\n..#..", "output": "No" }, { "input": "5 9\n........#\n#........\n..##.#...\n.......#.\n....#.#.#", "output": "No" }, { "input": "1 1\n#", "o...
46
0
0
2,801
592
The Monster and the Squirrel
[ "math" ]
null
null
Ari the monster always wakes up very early with the first ray of the sun and the first thing she does is feeding her squirrel. Ari draws a regular convex polygon on the floor and numbers it's vertices 1,<=2,<=...,<=*n* in clockwise order. Then starting from the vertex 1 she draws a ray in the direction of each other v...
The first and only line of the input contains a single integer *n* (3<=≤<=*n*<=≤<=54321) - the number of vertices of the regular polygon drawn by Ari.
Print the minimum number of jumps Ada should make to collect all the walnuts. Note, that she doesn't need to leave the polygon after.
[ "5\n", "3\n" ]
[ "9\n", "1\n" ]
One of the possible solutions for the first sample is shown on the picture above.
[ { "input": "5", "output": "9" }, { "input": "3", "output": "1" }, { "input": "54321", "output": "2950553761" }, { "input": "4", "output": "4" }, { "input": "6", "output": "16" }, { "input": "7", "output": "25" }, { "input": "8", "output...
77
1,228,800
3
2,805
0
none
[ "none" ]
null
null
Valery is very interested in magic. Magic attracts him so much that he sees it everywhere. He explains any strange and weird phenomenon through intervention of supernatural forces. But who would have thought that even in a regular array of numbers Valera manages to see something beautiful and magical. Valera absolutel...
The first line of the input data contains an integer *n* (1<=≤<=*n*<=≤<=105). The second line contains an array of original integers *a*1,<=*a*2,<=...,<=*a**n* (<=-<=109<=≤<=*a**i*<=≤<=109).
Print on the single line the answer to the problem: the amount of subarrays, which are magical. Please do not use the %lld specificator to read or write 64-bit numbers in C++. It is recommended to use cin, cout streams (you can also use the %I64d specificator).
[ "4\n2 1 1 4\n", "5\n-2 -2 -2 0 1\n" ]
[ "5\n", "8\n" ]
Notes to sample tests: Magical subarrays are shown with pairs of indices [a;b] of the beginning and the end. In the first sample: [1;1], [2;2], [3;3], [4;4], [2;3]. In the second sample: [1;1], [2;2], [3;3], [4;4], [5;5], [1;2], [2;3], [1;3].
[ { "input": "4\n2 1 1 4", "output": "5" }, { "input": "5\n-2 -2 -2 0 1", "output": "8" }, { "input": "1\n10", "output": "1" }, { "input": "2\n5 6", "output": "2" }, { "input": "5\n5 5 4 5 5", "output": "7" }, { "input": "8\n1 2 0 0 0 0 3 3", "output...
280
14,643,200
3
2,806
0
none
[ "none" ]
null
null
Stepan has the newest electronic device with a display. Different digits can be shown on it. Each digit is shown on a seven-section indicator like it is shown on the picture below. So, for example, to show the digit 3 on the display, 5 sections must be highlighted; and for the digit 6, 6 sections must be highlighted. ...
The first line contains the integer *n* (2<=≤<=*n*<=≤<=100<=000) — the maximum number of sections which can be highlighted on the display.
Print the maximum integer which can be shown on the display of Stepan's newest device.
[ "2\n", "3\n" ]
[ "1\n", "7\n" ]
none
[ { "input": "2", "output": "1" }, { "input": "3", "output": "7" }, { "input": "4", "output": "11" }, { "input": "5", "output": "71" }, { "input": "6", "output": "111" }, { "input": "85651", "output": "711111111111111111111111111111111111111111111111...
202
28,672,000
3
2,808
36
Fractal
[ "implementation" ]
B. Fractal
2
64
Ever since Kalevitch, a famous Berland abstractionist, heard of fractals, he made them the main topic of his canvases. Every morning the artist takes a piece of graph paper and starts with making a model of his future canvas. He takes a square as big as *n*<=×<=*n* squares and paints some of them black. Then he takes a...
The first line contains integers *n* and *k* (2<=≤<=*n*<=≤<=3, 1<=≤<=*k*<=≤<=5), where *k* is the amount of steps of the algorithm. Each of the following *n* lines contains *n* symbols that determine the model. Symbol «.» stands for a white square, whereas «*» stands for a black one. It is guaranteed that the model has...
Output a matrix *n**k*<=×<=*n**k* which is what a picture should look like after *k* steps of the algorithm.
[ "2 3\n.*\n..\n", "3 2\n.*.\n***\n.*.\n" ]
[ ".*******\n..******\n.*.*****\n....****\n.***.***\n..**..**\n.*.*.*.*\n........\n", ".*.***.*.\n*********\n.*.***.*.\n*********\n*********\n*********\n.*.***.*.\n*********\n.*.***.*.\n" ]
none
[ { "input": "2 3\n.*\n..", "output": ".*******\n..******\n.*.*****\n....****\n.***.***\n..**..**\n.*.*.*.*\n........" }, { "input": "3 2\n.*.\n***\n.*.", "output": ".*.***.*.\n*********\n.*.***.*.\n*********\n*********\n*********\n.*.***.*.\n*********\n.*.***.*." }, { "input": "2 1\n..\n....
154
307,200
-1
2,810
675
Tree Construction
[ "data structures", "trees" ]
null
null
During the programming classes Vasya was assigned a difficult problem. However, he doesn't know how to code and was unable to find the solution in the Internet, so he asks you to help. You are given a sequence $a$, consisting of $n$ distinct integers, that is used to construct the binary search tree. Below is the form...
The first line of the input contains a single integer $n$ ($2 \leq n \leq 100\,000$) — the length of the sequence $a$. The second line contains $n$ distinct integers $a_i$ ($1 \leq a_i \leq 10^9$) — the sequence $a$ itself.
Output $n - 1$ integers. For all $i &gt; 1$ print the value written in the node that is the parent of the node with value $a_i$ in it.
[ "3\n1 2 3\n", "5\n4 2 3 1 6\n" ]
[ "1 2\n", "4 2 2 4\n" ]
none
[ { "input": "3\n1 2 3", "output": "1 2" }, { "input": "5\n4 2 3 1 6", "output": "4 2 2 4" }, { "input": "2\n1 2", "output": "1" }, { "input": "10\n991309218 517452607 870021923 978357992 136426010 10601767 302627526 883615372 163475700 600546765", "output": "991309218 5174...
280
7,884,800
-1
2,821
204
Little Elephant and Cards
[ "binary search", "data structures" ]
null
null
The Little Elephant loves to play with color cards. He has *n* cards, each has exactly two colors (the color of the front side and the color of the back side). Initially, all the cards lay on the table with the front side up. In one move the Little Elephant can turn any card to the other side. The Little Elephant thin...
The first line contains a single integer *n* (1<=≤<=*n*<=≤<=105) — the number of the cards. The following *n* lines contain the description of all cards, one card per line. The cards are described by a pair of positive integers not exceeding 109 — colors of both sides. The first number in a line is the color of the fro...
On a single line print a single integer — the sought minimum number of moves. If it is impossible to make the set funny, print -1.
[ "3\n4 7\n4 7\n7 4\n", "5\n4 7\n7 4\n2 11\n9 7\n1 1\n" ]
[ "0\n", "2\n" ]
In the first sample there initially are three cards lying with colors 4, 4, 7. Since two of the three cards are of the same color 4, you do not need to change anything, so the answer is 0. In the second sample, you can turn the first and the fourth cards. After that three of the five cards will be of color 7.
[ { "input": "3\n4 7\n4 7\n7 4", "output": "0" }, { "input": "5\n4 7\n7 4\n2 11\n9 7\n1 1", "output": "2" }, { "input": "1\n1 1", "output": "0" }, { "input": "2\n1 1\n1 1", "output": "0" }, { "input": "7\n1 2\n2 3\n3 4\n4 5\n5 6\n6 7\n7 8", "output": "-1" }, ...
124
614,400
0
2,825
990
Micro-World
[ "greedy", "sortings" ]
null
null
You have a Petri dish with bacteria and you are preparing to dive into the harsh micro-world. But, unfortunately, you don't have any microscope nearby, so you can't watch them. You know that you have $n$ bacteria in the Petri dish and size of the $i$-th bacteria is $a_i$. Also you know intergalactic positive integer c...
The first line contains two space separated positive integers $n$ and $K$ ($1 \le n \le 2 \cdot 10^5$, $1 \le K \le 10^6$) — number of bacteria and intergalactic constant $K$. The second line contains $n$ space separated integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^6$) — sizes of bacteria you have.
Print the only integer — minimal possible number of bacteria can remain.
[ "7 1\n101 53 42 102 101 55 54\n", "6 5\n20 15 10 15 20 25\n", "7 1000000\n1 1 1 1 1 1 1\n" ]
[ "3\n", "1\n", "7\n" ]
The first example is clarified in the problem statement. In the second example an optimal possible sequence of swallows is: $[20, 15, 10, 15, \underline{20}, 25]$ $\to$ $[20, 15, 10, \underline{15}, 25]$ $\to$ $[20, 15, \underline{10}, 25]$ $\to$ $[20, \underline{15}, 25]$ $\to$ $[\underline{20}, 25]$ $\to$ $[25]$. I...
[ { "input": "7 1\n101 53 42 102 101 55 54", "output": "3" }, { "input": "6 5\n20 15 10 15 20 25", "output": "1" }, { "input": "7 1000000\n1 1 1 1 1 1 1", "output": "7" }, { "input": "1 1\n1", "output": "1" }, { "input": "1 4\n8", "output": "1" }, { "inp...
2,000
14,848,000
0
2,828
471
MUH and Sticks
[ "implementation" ]
null
null
Two polar bears Menshykov and Uslada from the St.Petersburg zoo and elephant Horace from the Kiev zoo got six sticks to play with and assess the animals' creativity. Menshykov, Uslada and Horace decided to make either an elephant or a bear from those sticks. They can make an animal from sticks in the following way: -...
The single line contains six space-separated integers *l**i* (1<=≤<=*l**i*<=≤<=9) — the lengths of the six sticks. It is guaranteed that the input is such that you cannot make both animals from the sticks.
If you can make a bear from the given set, print string "Bear" (without the quotes). If you can make an elephant, print string "Elephant" (wıthout the quotes). If you can make neither a bear nor an elephant, print string "Alien" (without the quotes).
[ "4 2 5 4 4 4\n", "4 4 5 4 4 5\n", "1 2 3 4 5 6\n" ]
[ "Bear", "Elephant", "Alien" ]
If you're out of creative ideas, see instructions below which show how to make a bear and an elephant in the first two samples. The stick of length 2 is in red, the sticks of length 4 are in green, the sticks of length 5 are in blue.
[ { "input": "4 2 5 4 4 4", "output": "Bear" }, { "input": "4 4 5 4 4 5", "output": "Elephant" }, { "input": "1 2 3 4 5 6", "output": "Alien" }, { "input": "5 5 5 5 5 5", "output": "Elephant" }, { "input": "1 1 1 2 3 5", "output": "Alien" }, { "input": "...
46
0
0
2,831
292
SMSC
[ "implementation" ]
null
null
Some large corporation where Polycarpus works has its own short message service center (SMSC). The center's task is to send all sorts of crucial information. Polycarpus decided to check the efficiency of the SMSC. For that, he asked to give him the statistics of the performance of the SMSC for some period of time. In...
The first line contains a single integer *n* (1<=≤<=*n*<=≤<=103) — the number of tasks of the SMSC. Next *n* lines contain the tasks' descriptions: the *i*-th line contains two space-separated integers *t**i* and *c**i* (1<=≤<=*t**i*,<=*c**i*<=≤<=106) — the time (the second) when the *i*-th task was received and the nu...
In a single line print two space-separated integers — the time when the last text message was sent and the maximum queue size at a certain moment of time.
[ "2\n1 1\n2 1\n", "1\n1000000 10\n", "3\n3 3\n4 3\n5 3\n" ]
[ "3 1\n", "1000010 10\n", "12 7\n" ]
In the first test sample: - second 1: the first message has appeared in the queue, the queue's size is 1; - second 2: the first message is sent, the second message has been received, the queue's size is 1; - second 3: the second message is sent, the queue's size is 0, Thus, the maximum size of the queue is 1, the...
[ { "input": "2\n1 1\n2 1", "output": "3 1" }, { "input": "1\n1000000 10", "output": "1000010 10" }, { "input": "3\n3 3\n4 3\n5 3", "output": "12 7" }, { "input": "1\n1 1", "output": "2 1" }, { "input": "2\n1 11\n100 10", "output": "110 11" }, { "input":...
154
6,963,200
3
2,834
65
Harry Potter and Moving Staircases
[ "dfs and similar", "implementation" ]
E. Harry Potter and Moving Staircases
2
256
Harry Potter lost his Invisibility Cloak, running from the school caretaker Filch. Finding an invisible object is not an easy task. Fortunately, Harry has friends who are willing to help. Hermione Granger had read "The Invisibility Cloaks, and Everything about Them", as well as six volumes of "The Encyclopedia of Quick...
The first line contains integers *n* and *m* (1<=≤<=*n*<=≤<=100000, 0<=≤<=*m*<=≤<=200000), which are the number of floors and staircases in Hogwarts, respectively. The following *m* lines contain pairs of floors connected by staircases at the initial moment of time.
In the first line print "YES" (without the quotes) if Harry is able to search all the floors, and "NO" otherwise. If the answer is positive, then print on the second line the number of staircases that Ron and Hermione will have to shift. Further output should look like this: Harry's moves a staircase's move Harry'...
[ "6 4\n1 2\n1 3\n2 3\n4 5\n", "4 1\n1 2\n", "5 5\n1 2\n1 3\n3 4\n3 5\n4 5\n" ]
[ "YES\n2\n3 1 2 3\n2 3 5\n3 5 4 5\n4 5 6\n3 6 5 3\n", "NO\n", "YES\n0\n6 1 2 1 3 4 5\n" ]
none
[]
0
0
-1
2,837
340
Maximal Area Quadrilateral
[ "brute force", "geometry" ]
null
null
Iahub has drawn a set of *n* points in the cartesian plane which he calls "special points". A quadrilateral is a simple polygon without self-intersections with four sides (also called edges) and four vertices (also called corners). Please note that a quadrilateral doesn't have to be convex. A special quadrilateral is o...
The first line contains integer *n* (4<=≤<=*n*<=≤<=300). Each of the next *n* lines contains two integers: *x**i*, *y**i* (<=-<=1000<=≤<=*x**i*,<=*y**i*<=≤<=1000) — the cartesian coordinates of *i*th special point. It is guaranteed that no three points are on the same line. It is guaranteed that no two points coincide.
Output a single real number — the maximal area of a special quadrilateral. The answer will be considered correct if its absolute or relative error does't exceed 10<=-<=9.
[ "5\n0 0\n0 4\n4 0\n4 4\n2 3\n" ]
[ "16.000000" ]
In the test example we can choose first 4 points to be the vertices of the quadrilateral. They form a square by side 4, so the area is 4·4 = 16.
[ { "input": "5\n0 0\n0 4\n4 0\n4 4\n2 3", "output": "16.000000" }, { "input": "10\n-6 -4\n-7 5\n-7 -7\n5 -7\n4 -9\n-6 7\n2 9\n-4 -6\n2 10\n-10 -4", "output": "166.000000" }, { "input": "4\n-3 3\n0 3\n-2 -1\n2 2", "output": "11.000000" }, { "input": "5\n-4 -3\n-3 -2\n3 3\n-1 2\...
1,000
307,200
0
2,838
5
Center Alignment
[ "implementation", "strings" ]
B. Center Alignment
1
64
Almost every text editor has a built-in function of center text alignment. The developers of the popular in Berland text editor «Textpad» decided to introduce this functionality into the fourth release of the product. You are to implement the alignment in the shortest possible time. Good luck!
The input file consists of one or more lines, each of the lines contains Latin letters, digits and/or spaces. The lines cannot start or end with a space. It is guaranteed that at least one of the lines has positive length. The length of each line and the total amount of the lines do not exceed 1000.
Format the given text, aligning it center. Frame the whole text with characters «*» of the minimum size. If a line cannot be aligned perfectly (for example, the line has even length, while the width of the block is uneven), you should place such lines rounding down the distance to the left or to the right edge and brin...
[ "This is\n\nCodeforces\nBeta\nRound\n5\n", "welcome to the\nCodeforces\nBeta\nRound 5\n\nand\ngood luck\n" ]
[ "************\n* This is *\n* *\n*Codeforces*\n* Beta *\n* Round *\n* 5 *\n************\n", "****************\n*welcome to the*\n* Codeforces *\n* Beta *\n* Round 5 *\n* *\n* and *\n* good luck *\n****************\n" ]
none
[ { "input": "This is\n\nCodeforces\nBeta\nRound\n5", "output": "************\n* This is *\n* *\n*Codeforces*\n* Beta *\n* Round *\n* 5 *\n************" }, { "input": "welcome to the\nCodeforces\nBeta\nRound 5\n\nand\ngood luck", "output": "****************\n*welcome to th...
92
0
0
2,839
476
Dreamoon and WiFi
[ "bitmasks", "brute force", "combinatorics", "dp", "math", "probabilities" ]
null
null
Dreamoon is standing at the position 0 on a number line. Drazil is sending a list of commands through Wi-Fi to Dreamoon's smartphone and Dreamoon follows them. Each command is one of the following two types: 1. Go 1 unit towards the positive direction, denoted as '+' 1. Go 1 unit towards the negative direction, de...
The first line contains a string *s*1 — the commands Drazil sends to Dreamoon, this string consists of only the characters in the set {'+', '-'}. The second line contains a string *s*2 — the commands Dreamoon's smartphone recognizes, this string consists of only the characters in the set {'+', '-', '?'}. '?' denotes ...
Output a single real number corresponding to the probability. The answer will be considered correct if its relative or absolute error doesn't exceed 10<=-<=9.
[ "++-+-\n+-+-+\n", "+-+-\n+-??\n", "+++\n??-\n" ]
[ "1.000000000000\n", "0.500000000000\n", "0.000000000000\n" ]
For the first sample, both *s*<sub class="lower-index">1</sub> and *s*<sub class="lower-index">2</sub> will lead Dreamoon to finish at the same position  + 1. For the second sample, *s*<sub class="lower-index">1</sub> will lead Dreamoon to finish at position 0, while there are four possibilites for *s*<sub class="low...
[ { "input": "++-+-\n+-+-+", "output": "1.000000000000" }, { "input": "+-+-\n+-??", "output": "0.500000000000" }, { "input": "+++\n??-", "output": "0.000000000000" }, { "input": "++++++++++\n+++??++?++", "output": "0.125000000000" }, { "input": "--+++---+-\n????????...
218
9,420,800
0
2,844
840
In a Trap
[ "trees" ]
null
null
Lech got into a tree consisting of *n* vertices with a root in vertex number 1. At each vertex *i* written integer *a**i*. He will not get out until he answers *q* queries of the form *u* *v*. Answer for the query is maximal value among all vertices *i* on path from *u* to *v* including *u* and *v*, where *dist*(*i*,<...
First line of input data contains two integers *n* and *q* (1<=≤<=*n*<=≤<=5·104, 1<=≤<=*q*<=≤<=150<=000) — number of vertices in the tree and number of queries respectively. Next line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (0<=≤<=*a**i*<=≤<=*n*) — numbers on vertices. Each of next *n*<=-<=1 lines contains t...
Output *q* lines — answers for a queries.
[ "5 3\n0 3 2 1 4\n1 2\n2 3\n3 4\n3 5\n1 4\n1 5\n2 4\n", "5 4\n1 2 3 4 5\n1 2\n2 3\n3 4\n4 5\n1 5\n2 5\n1 4\n3 3\n" ]
[ "3\n4\n3\n", "5\n5\n4\n3\n" ]
none
[]
30
0
0
2,860
915
Garden
[ "implementation" ]
null
null
Luba thinks about watering her garden. The garden can be represented as a segment of length *k*. Luba has got *n* buckets, the *i*-th bucket allows her to water some continuous subsegment of garden of length exactly *a**i* each hour. Luba can't water any parts of the garden that were already watered, also she can't wat...
The first line of input contains two integer numbers *n* and *k* (1<=≤<=*n*,<=*k*<=≤<=100) — the number of buckets and the length of the garden, respectively. The second line of input contains *n* integer numbers *a**i* (1<=≤<=*a**i*<=≤<=100) — the length of the segment that can be watered by the *i*-th bucket in one ...
Print one integer number — the minimum number of hours required to water the garden.
[ "3 6\n2 3 5\n", "6 7\n1 2 3 4 5 6\n" ]
[ "2\n", "7\n" ]
In the first test the best option is to choose the bucket that allows to water the segment of length 3. We can't choose the bucket that allows to water the segment of length 5 because then we can't water the whole garden. In the second test we can choose only the bucket that allows us to water the segment of length 1.
[ { "input": "3 6\n2 3 5", "output": "2" }, { "input": "6 7\n1 2 3 4 5 6", "output": "7" }, { "input": "5 97\n1 10 50 97 2", "output": "1" }, { "input": "5 97\n1 10 50 100 2", "output": "97" }, { "input": "100 100\n2 46 24 18 86 90 31 38 84 49 58 28 15 80 14 24 87 5...
109
0
3
2,875
818
Multicolored Cars
[ "data structures", "implementation" ]
null
null
Alice and Bob got very bored during a long car trip so they decided to play a game. From the window they can see cars of different colors running past them. Cars are going one after another. The game rules are like this. Firstly Alice chooses some color *A*, then Bob chooses some color *B* (*A*<=≠<=*B*). After each ca...
The first line contains two integer numbers *n* and *A* (1<=≤<=*n*<=≤<=105,<=1<=≤<=*A*<=≤<=106) – number of cars and the color chosen by Alice. The second line contains *n* integer numbers *c*1,<=*c*2,<=...,<=*c**n* (1<=≤<=*c**i*<=≤<=106) — colors of the cars that Alice and Bob will encounter in the order of their app...
Output such color *B* (1<=≤<=*B*<=≤<=106) that if Bob chooses it then he will win the game. If there are multiple solutions, print any of them. If there is no such color then print -1. It is guaranteed that if there exists any solution then there exists solution with (1<=≤<=*B*<=≤<=106).
[ "4 1\n2 1 4 2\n", "5 2\n2 2 4 5 3\n", "3 10\n1 2 3\n" ]
[ "2\n", "-1\n", "4\n" ]
Let's consider availability of colors in the first example: - *cnt*<sub class="lower-index">2</sub>(*i*) ≥ *cnt*<sub class="lower-index">1</sub>(*i*) for every *i*, and color 2 can be the answer. - *cnt*<sub class="lower-index">4</sub>(2) &lt; *cnt*<sub class="lower-index">1</sub>(2), so color 4 isn't the winning o...
[ { "input": "4 1\n2 1 4 2", "output": "2" }, { "input": "5 2\n2 2 4 5 3", "output": "-1" }, { "input": "3 10\n1 2 3", "output": "4" }, { "input": "1 1\n2", "output": "3" }, { "input": "1 2\n2", "output": "-1" }, { "input": "10 6\n8 5 1 6 6 5 10 6 9 8", ...
62
5,529,600
0
2,888
869
The Eternal Immortality
[ "math" ]
null
null
Even if the world is full of counterfeits, I still regard it as wonderful. Pile up herbs and incense, and arise again from the flames and ashes of its predecessor — as is known to many, the phoenix does it like this. The phoenix has a rather long lifespan, and reincarnates itself once every *a*! years. Here *a*! deno...
The first and only line of input contains two space-separated integers *a* and *b* (0<=≤<=*a*<=≤<=*b*<=≤<=1018).
Output one line containing a single decimal digit — the last digit of the value that interests Koyomi.
[ "2 4\n", "0 10\n", "107 109\n" ]
[ "2\n", "0\n", "2\n" ]
In the first example, the last digit of <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/99c47ca8b182f097e38094d12f0c06ce0b081b76.png" style="max-width: 100.0%;max-height: 100.0%;"/> is 2; In the second example, the last digit of <img align="middle" class="tex-formula" src="https://espresso...
[ { "input": "2 4", "output": "2" }, { "input": "0 10", "output": "0" }, { "input": "107 109", "output": "2" }, { "input": "10 13", "output": "6" }, { "input": "998244355 998244359", "output": "4" }, { "input": "999999999000000000 1000000000000000000", ...
61
5,529,600
0
2,901
914
Substrings in a String
[ "bitmasks", "brute force", "data structures", "string suffix structures", "strings" ]
null
null
Given a string *s*, process *q* queries, each having one of the following forms: - 1<=*i*<=*c* — Change the *i*-th character in the string to *c*. - 2<=*l*<=*r*<=*y* — Consider the substring of *s* starting at position *l* and ending at position *r*. Output the number of times *y* occurs as a substring in it.
The first line of the input contains the string *s* (1<=≤<=|*s*|<=≤<=105) of lowercase English letters. The second line contains an integer *q* (1<=≤<=*q*<=≤<=105)  — the number of queries to process. The next *q* lines describe the queries and may have one of the following forms: - 1<=*i*<=*c* (1<=≤<=*i*<=≤<=|*s*|...
For each query of type 2, output the required answer in a separate line.
[ "ababababa\n3\n2 1 7 aba\n1 5 c\n2 1 7 aba\n", "abcdcbc\n5\n2 1 7 bc\n1 4 b\n2 4 7 bc\n1 2 a\n2 1 4 aa\n" ]
[ "3\n1\n", "2\n2\n1\n" ]
Consider the first sample case. Initially, the string aba occurs 3 times in the range [1, 7]. Note that two occurrences may overlap. After the update, the string becomes ababcbaba and now aba occurs only once in the range [1, 7].
[]
30
0
-1
2,905
981
Bookshelves
[ "bitmasks", "dp", "greedy" ]
null
null
Mr Keks is a typical white-collar in Byteland. He has a bookshelf in his office with some books on it, each book has an integer positive price. Mr Keks defines the value of a shelf as the sum of books prices on it. Miraculously, Mr Keks was promoted and now he is moving into a new office. He learned that in the ne...
The first line contains two integers $n$ and $k$ ($1 \leq k \leq n \leq 50$) — the number of books and the number of shelves in the new office. The second line contains $n$ integers $a_1, a_2, \ldots a_n$, ($0 &lt; a_i &lt; 2^{50}$) — the prices of the books in the order they stand on the old shelf.
Print the maximum possible beauty of $k$ shelves in the new office.
[ "10 4\n9 14 28 1 7 13 15 29 2 31\n", "7 3\n3 14 15 92 65 35 89\n" ]
[ "24\n", "64\n" ]
In the first example you can split the books as follows: $$(9 + 14 + 28 + 1 + 7) \&amp; (13 + 15) \&amp; (29 + 2) \&amp; (31) = 24.$$ In the second example you can split the books as follows: $$(3 + 14 + 15 + 92) \&amp; (65) \&amp; (35 + 89) = 64.$$
[ { "input": "10 4\n9 14 28 1 7 13 15 29 2 31", "output": "24" }, { "input": "7 3\n3 14 15 92 65 35 89", "output": "64" }, { "input": "40 5\n6 18 24 5 14 16 31 9 15 5 25 2 18 12 19 27 10 23 23 18 22 14 1 14 6 14 17 28 11 21 8 23 10 30 21 5 17 11 26 16", "output": "80" }, { "inp...
639
9,420,800
3
2,912
965
Greedy Arkady
[ "math" ]
null
null
$k$ people want to split $n$ candies between them. Each candy should be given to exactly one of them or be thrown away. The people are numbered from $1$ to $k$, and Arkady is the first of them. To split the candies, Arkady will choose an integer $x$ and then give the first $x$ candies to himself, the next $x$ candies ...
The only line contains four integers $n$, $k$, $M$ and $D$ ($2 \le n \le 10^{18}$, $2 \le k \le n$, $1 \le M \le n$, $1 \le D \le \min{(n, 1000)}$, $M \cdot D \cdot k \ge n$) — the number of candies, the number of people, the maximum number of candies given to a person at once, the maximum number of times a person can ...
Print a single integer — the maximum possible number of candies Arkady can give to himself. Note that it is always possible to choose some valid $x$.
[ "20 4 5 2\n", "30 9 4 1\n" ]
[ "8\n", "4\n" ]
In the first example Arkady should choose $x = 4$. He will give $4$ candies to himself, $4$ candies to the second person, $4$ candies to the third person, then $4$ candies to the fourth person and then again $4$ candies to himself. No person is given candies more than $2$ times, and Arkady receives $8$ candies in total...
[ { "input": "20 4 5 2", "output": "8" }, { "input": "30 9 4 1", "output": "4" }, { "input": "2 2 1 1", "output": "1" }, { "input": "42 20 5 29", "output": "5" }, { "input": "1000000000000000000 135 1000000000000000 1000", "output": "8325624421831635" }, { ...
124
0
0
2,914
101
Homework
[ "greedy" ]
A. Homework
2
256
Once when Gerald studied in the first year at school, his teacher gave the class the following homework. She offered the students a string consisting of *n* small Latin letters; the task was to learn the way the letters that the string contains are written. However, as Gerald is too lazy, he has no desire whatsoever to...
The first input data line contains a string whose length is equal to *n* (1<=≤<=*n*<=≤<=105). The string consists of lowercase Latin letters. The second line contains the number *k* (0<=≤<=*k*<=≤<=105).
Print on the first line the only number *m* — the least possible number of different characters that could remain in the given string after it loses no more than *k* characters. Print on the second line the string that Gerald can get after some characters are lost. The string should have exactly *m* distinct character...
[ "aaaaa\n4\n", "abacaba\n4\n", "abcdefgh\n10\n" ]
[ "1\naaaaa\n", "1\naaaa\n", "0\n\n" ]
In the first sample the string consists of five identical letters but you are only allowed to delete 4 of them so that there was at least one letter left. Thus, the right answer is 1 and any string consisting of characters "a" from 1 to 5 in length. In the second sample you are allowed to delete 4 characters. You cann...
[ { "input": "aaaaa\n4", "output": "1\naaaaa" }, { "input": "abacaba\n4", "output": "1\naaaa" }, { "input": "abcdefgh\n10", "output": "0" }, { "input": "aaaaaaaaaaaaaaaaaaaa\n19", "output": "1\naaaaaaaaaaaaaaaaaaaa" }, { "input": "abcdefghijjihgedcba\n0", "outpu...
186
921,600
3.951783
2,928
1,009
Game Shopping
[ "implementation" ]
null
null
Maxim wants to buy some games at the local game shop. There are $n$ games in the shop, the $i$-th game costs $c_i$. Maxim has a wallet which can be represented as an array of integers. His wallet contains $m$ bills, the $j$-th bill has value $a_j$. Games in the shop are ordered from left to right, Maxim tries to buy ...
The first line of the input contains two integers $n$ and $m$ ($1 \le n, m \le 1000$) — the number of games and the number of bills in Maxim's wallet. The second line of the input contains $n$ integers $c_1, c_2, \dots, c_n$ ($1 \le c_i \le 1000$), where $c_i$ is the cost of the $i$-th game. The third line of the inp...
Print a single integer — the number of games Maxim will buy.
[ "5 4\n2 4 5 2 4\n5 3 4 6\n", "5 2\n20 40 50 20 40\n19 20\n", "6 4\n4 8 15 16 23 42\n1000 1000 1000 1000\n" ]
[ "3\n", "0\n", "4\n" ]
The first example is described in the problem statement. In the second example Maxim cannot buy any game because the value of the first bill in his wallet is smaller than the cost of any game in the shop. In the third example the values of the bills in Maxim's wallet are large enough to buy any game he encounter unti...
[ { "input": "5 4\n2 4 5 2 4\n5 3 4 6", "output": "3" }, { "input": "5 2\n20 40 50 20 40\n19 20", "output": "0" }, { "input": "6 4\n4 8 15 16 23 42\n1000 1000 1000 1000", "output": "4" }, { "input": "5 1\n1 1 1 1 1\n5", "output": "1" }, { "input": "5 1\n10 1 1 1 1\n...
46
716,800
3
2,941
828
Restaurant Tables
[ "implementation" ]
null
null
In a small restaurant there are *a* tables for one person and *b* tables for two persons. It it known that *n* groups of people come today, each consisting of one or two people. If a group consist of one person, it is seated at a vacant one-seater table. If there are none of them, it is seated at a vacant two-seate...
The first line contains three integers *n*, *a* and *b* (1<=≤<=*n*<=≤<=2·105, 1<=≤<=*a*,<=*b*<=≤<=2·105) — the number of groups coming to the restaurant, the number of one-seater and the number of two-seater tables. The second line contains a sequence of integers *t*1,<=*t*2,<=...,<=*t**n* (1<=≤<=*t**i*<=≤<=2) — the d...
Print the total number of people the restaurant denies service to.
[ "4 1 2\n1 2 1 1\n", "4 1 1\n1 1 2 1\n" ]
[ "0\n", "2\n" ]
In the first example the first group consists of one person, it is seated at a vacant one-seater table. The next group occupies a whole two-seater table. The third group consists of one person, it occupies one place at the remaining two-seater table. The fourth group consists of one person, he is seated at the remainin...
[ { "input": "4 1 2\n1 2 1 1", "output": "0" }, { "input": "4 1 1\n1 1 2 1", "output": "2" }, { "input": "1 1 1\n1", "output": "0" }, { "input": "2 1 2\n2 2", "output": "0" }, { "input": "5 1 3\n1 2 2 2 1", "output": "1" }, { "input": "7 6 1\n1 1 1 1 1 1...
218
3,481,600
0
2,943
888
Local Extrema
[ "brute force", "implementation" ]
null
null
You are given an array *a*. Some element of this array *a**i* is a local minimum iff it is strictly less than both of its neighbours (that is, *a**i*<=&lt;<=*a**i*<=-<=1 and *a**i*<=&lt;<=*a**i*<=+<=1). Also the element can be called local maximum iff it is strictly greater than its neighbours (that is, *a**i*<=&gt;<=*...
The first line contains one integer *n* (1<=≤<=*n*<=≤<=1000) — the number of elements in array *a*. The second line contains *n* integers *a*1, *a*2, ..., *a**n* (1<=≤<=*a**i*<=≤<=1000) — the elements of array *a*.
Print the number of local extrema in the given array.
[ "3\n1 2 3\n", "4\n1 5 2 5\n" ]
[ "0\n", "2\n" ]
none
[ { "input": "3\n1 2 3", "output": "0" }, { "input": "4\n1 5 2 5", "output": "2" }, { "input": "1\n1", "output": "0" }, { "input": "1\n548", "output": "0" }, { "input": "2\n1 1", "output": "0" }, { "input": "3\n3 2 3", "output": "1" }, { "inp...
61
6,963,200
3
2,966
120
Winnie-the-Pooh and honey
[ "implementation", "math" ]
null
null
As we all know, Winnie-the-Pooh just adores honey. Ones he and the Piglet found out that the Rabbit has recently gotten hold of an impressive amount of this sweet and healthy snack. As you may guess, Winnie and the Piglet asked to come at the Rabbit's place. Thus, there are *n* jars of honey lined up in front of Winnie...
The first line contains two integers *n* and *k* (1<=≤<=*n*<=≤<=100,<=1<=≤<=*k*<=≤<=100). The second line contains *n* integers *a*1, *a*2, ..., *a**n*, separated by spaces (1<=≤<=*a**i*<=≤<=100).
Print a single number — how many kilos of honey gets Piglet.
[ "3 3\n15 8 10\n" ]
[ "9\n" ]
none
[ { "input": "3 3\n15 8 10", "output": "9" }, { "input": "1 3\n3", "output": "0" }, { "input": "3 4\n3 8 2", "output": "5" }, { "input": "3 2\n95 25 49", "output": "151" }, { "input": "3 1\n8 3 2", "output": "5" }, { "input": "5 1\n4 7 9 5 7", "outpu...
186
0
-1
2,968
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...
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: {...
[ { "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",...
109
0
3
2,976
18
Platforms
[ "brute force", "math" ]
B. Platforms
2
64
In one one-dimensional world there are *n* platforms. Platform with index *k* (platforms are numbered from 1) is a segment with coordinates [(*k*<=-<=1)*m*,<=(*k*<=-<=1)*m*<=+<=*l*], and *l*<=&lt;<=*m*. Grasshopper Bob starts to jump along the platforms from point 0, with each jump he moves exactly *d* units right. Fin...
The first input line contains 4 integer numbers *n*, *d*, *m*, *l* (1<=≤<=*n*,<=*d*,<=*m*,<=*l*<=≤<=106,<=*l*<=&lt;<=*m*) — respectively: amount of platforms, length of the grasshopper Bob's jump, and numbers *m* and *l* needed to find coordinates of the *k*-th platform: [(*k*<=-<=1)*m*,<=(*k*<=-<=1)*m*<=+<=*l*].
Output the coordinates of the point, where the grosshopper will fall down. Don't forget that if Bob finds himself on the platform edge, he doesn't fall down.
[ "2 2 5 3\n", "5 4 11 8\n" ]
[ "4\n", "20\n" ]
none
[ { "input": "2 2 5 3", "output": "4" }, { "input": "5 4 11 8", "output": "20" }, { "input": "228385 744978 699604 157872", "output": "2979912" }, { "input": "773663 427904 329049 243542", "output": "1283712" }, { "input": "835293 627183 442142 361649", "output"...
528
20,889,600
3.71236
2,987
994
Fingerprints
[ "implementation" ]
null
null
You are locked in a room with a door that has a keypad with 10 keys corresponding to digits from 0 to 9. To escape from the room, you need to enter a correct code. You also have a sequence of digits. Some keys on the keypad have fingerprints. You believe the correct code is the longest not necessarily contiguous subse...
The first line contains two integers $n$ and $m$ ($1 \le n, m \le 10$) representing the number of digits in the sequence you have and the number of keys on the keypad that have fingerprints. The next line contains $n$ distinct space-separated integers $x_1, x_2, \ldots, x_n$ ($0 \le x_i \le 9$) representing the sequen...
In a single line print a space-separated sequence of integers representing the code. If the resulting sequence is empty, both printing nothing and printing a single line break is acceptable.
[ "7 3\n3 5 7 1 6 2 8\n1 2 7\n", "4 4\n3 4 1 0\n0 1 7 9\n" ]
[ "7 1 2\n", "1 0\n" ]
In the first example, the only digits with fingerprints are $1$, $2$ and $7$. All three of them appear in the sequence you know, $7$ first, then $1$ and then $2$. Therefore the output is 7 1 2. Note that the order is important, and shall be the same as the order in the original sequence. In the second example digits $...
[ { "input": "7 3\n3 5 7 1 6 2 8\n1 2 7", "output": "7 1 2" }, { "input": "4 4\n3 4 1 0\n0 1 7 9", "output": "1 0" }, { "input": "9 4\n9 8 7 6 5 4 3 2 1\n2 4 6 8", "output": "8 6 4 2" }, { "input": "10 5\n3 7 1 2 4 6 9 0 5 8\n4 3 0 7 9", "output": "3 7 4 9 0" }, { "...
109
0
3
2,990
44
Anfisa the Monkey
[ "dp" ]
E. Anfisa the Monkey
2
256
Anfisa the monkey learns to type. She is yet unfamiliar with the "space" key and can only type in lower-case Latin letters. Having typed for a fairly long line, Anfisa understood that it would be great to divide what she has written into *k* lines not shorter than *a* and not longer than *b*, for the text to resemble h...
The first line contains three integers *k*, *a* and *b* (1<=≤<=*k*<=≤<=200, 1<=≤<=*a*<=≤<=*b*<=≤<=200). The second line contains a sequence of lowercase Latin letters — the text typed by Anfisa. It is guaranteed that the given line is not empty and its length does not exceed 200 symbols.
Print *k* lines, each of which contains no less than *a* and no more than *b* symbols — Anfisa's text divided into lines. It is not allowed to perform any changes in the text, such as: deleting or adding symbols, changing their order, etc. If the solution is not unique, print any of them. If there is no solution, print...
[ "3 2 5\nabrakadabra\n", "4 1 2\nabrakadabra\n" ]
[ "ab\nrakad\nabra\n", "No solution\n" ]
none
[ { "input": "3 2 5\nabrakadabra", "output": "abra\nkada\nbra" }, { "input": "4 1 2\nabrakadabra", "output": "No solution" }, { "input": "3 1 2\nvgnfpo", "output": "vg\nnf\npo" }, { "input": "5 3 4\nvrrdnhazvexzjfv", "output": "vrr\ndnh\nazv\nexz\njfv" }, { "input":...
592
0
0
2,994
616
Comparing Two Long Integers
[ "implementation", "strings" ]
null
null
You are given two very long integers *a*,<=*b* (leading zeroes are allowed). You should check what number *a* or *b* is greater or determine that they are equal. The input size is very large so don't use the reading of symbols one by one. Instead of that use the reading of a whole line or token. As input/output can r...
The first line contains a non-negative integer *a*. The second line contains a non-negative integer *b*. The numbers *a*,<=*b* may contain leading zeroes. Each of them contains no more than 106 digits.
Print the symbol "&lt;" if *a*<=&lt;<=*b* and the symbol "&gt;" if *a*<=&gt;<=*b*. If the numbers are equal print the symbol "=".
[ "9\n10\n", "11\n10\n", "00012345\n12345\n", "0123\n9\n", "0123\n111\n" ]
[ "&lt;\n", "&gt;\n", "=\n", "&gt;\n", "&gt;\n" ]
none
[ { "input": "9\n10", "output": "<" }, { "input": "11\n10", "output": ">" }, { "input": "00012345\n12345", "output": "=" }, { "input": "0123\n9", "output": ">" }, { "input": "0123\n111", "output": ">" }, { "input": "9\n9", "output": "=" }, { ...
2,000
2,867,200
0
3,006
883
Quadcopter Competition
[ "greedy", "math" ]
null
null
Polycarp takes part in a quadcopter competition. According to the rules a flying robot should: - start the race from some point of a field, - go around the flag, - close cycle returning back to the starting point. Polycarp knows the coordinates of the starting point (*x*1,<=*y*1) and the coordinates of the point w...
The first line contains two integer numbers *x*1 and *y*1 (<=-<=100<=≤<=*x*1,<=*y*1<=≤<=100) — coordinates of the quadcopter starting (and finishing) point. The second line contains two integer numbers *x*2 and *y*2 (<=-<=100<=≤<=*x*2,<=*y*2<=≤<=100) — coordinates of the flag. It is guaranteed that the quadcopter sta...
Print the length of minimal path of the quadcopter to surround the flag and return back.
[ "1 5\n5 2\n", "0 1\n0 0\n" ]
[ "18\n", "8\n" ]
none
[ { "input": "1 5\n5 2", "output": "18" }, { "input": "0 1\n0 0", "output": "8" }, { "input": "-100 -100\n100 100", "output": "804" }, { "input": "-100 -100\n-100 100", "output": "406" }, { "input": "-100 -100\n100 -100", "output": "406" }, { "input": "1...
77
0
3
3,007
408
Garland
[ "implementation" ]
null
null
Once little Vasya read an article in a magazine on how to make beautiful handmade garland from colored paper. Vasya immediately went to the store and bought *n* colored sheets of paper, the area of each sheet is 1 square meter. The garland must consist of exactly *m* pieces of colored paper of arbitrary area, each pie...
The first line contains a non-empty sequence of *n* (1<=≤<=*n*<=≤<=1000) small English letters ("a"..."z"). Each letter means that Vasya has a sheet of paper of the corresponding color. The second line contains a non-empty sequence of *m* (1<=≤<=*m*<=≤<=1000) small English letters that correspond to the colors of the ...
Print an integer that is the maximum possible total area of the pieces of paper in the garland Vasya wants to get or -1, if it is impossible to make the garland from the sheets he's got. It is guaranteed that the answer is always an integer.
[ "aaabbac\naabbccac\n", "a\nz\n" ]
[ "6\n", "-1" ]
In the first test sample Vasya can make an garland of area 6: he can use both sheets of color *b*, three (but not four) sheets of color *a* and cut a single sheet of color *c* in three, for example, equal pieces. Vasya can use the resulting pieces to make a garland of area 6. In the second test sample Vasya cannot mak...
[ { "input": "aaabbac\naabbccac", "output": "6" }, { "input": "a\nz", "output": "-1" }, { "input": "r\nr", "output": "1" }, { "input": "stnsdn\nndnndsn", "output": "4" }, { "input": "yqfqfp\ntttwtqq", "output": "-1" }, { "input": "zzbbrrtrtzr\ntbbtrrrzr"...
46
0
0
3,016
547
Mike and Fish
[ "constructive algorithms", "dfs and similar", "graphs" ]
null
null
As everyone knows, bears love fish. But Mike is a strange bear; He hates fish! The even more strange thing about him is he has an infinite number of blue and red fish. He has marked *n* distinct points in the plane. *i*-th point is point (*x**i*,<=*y**i*). He wants to put exactly one fish in each of these points such...
The first line of input contains integer *n* (1<=≤<=*n*<=≤<=2<=×<=105). The next *n* lines contain the information about the points, *i*-th line contains two integers *x**i* and *y**i* (1<=≤<=*x**i*,<=*y**i*<=≤<=2<=×<=105), the *i*-th point coordinates. It is guaranteed that there is at least one valid answer.
Print the answer as a sequence of *n* characters 'r' (for red) or 'b' (for blue) where *i*-th character denotes the color of the fish in the *i*-th point.
[ "4\n1 1\n1 2\n2 1\n2 2\n", "3\n1 1\n1 2\n2 1\n" ]
[ "brrb\n", "brr\n" ]
none
[ { "input": "4\n1 1\n1 2\n2 1\n2 2", "output": "brrb" }, { "input": "3\n1 1\n1 2\n2 1", "output": "brr" }, { "input": "3\n157210 22861\n175396 39466\n40933 17093", "output": "rrr" }, { "input": "5\n55599 84144\n169207 98421\n1909 186625\n31525 147710\n7781 82078", "output"...
0
0
-1
3,019
385
Bear and Prime Numbers
[ "binary search", "brute force", "data structures", "dp", "implementation", "math", "number theory" ]
null
null
Recently, the bear started studying data structures and faced the following problem. You are given a sequence of integers *x*1,<=*x*2,<=...,<=*x**n* of length *n* and *m* queries, each of them is characterized by two integers *l**i*,<=*r**i*. Let's introduce *f*(*p*) to represent the number of such indexes *k*, that *...
The first line contains integer *n* (1<=≤<=*n*<=≤<=106). The second line contains *n* integers *x*1,<=*x*2,<=...,<=*x**n* (2<=≤<=*x**i*<=≤<=107). The numbers are not necessarily distinct. The third line contains integer *m* (1<=≤<=*m*<=≤<=50000). Each of the following *m* lines contains a pair of space-separated integ...
Print *m* integers — the answers to the queries on the order the queries appear in the input.
[ "6\n5 5 7 10 14 15\n3\n2 11\n3 12\n4 4\n", "7\n2 3 5 7 11 4 8\n2\n8 10\n2 123\n" ]
[ "9\n7\n0\n", "0\n7\n" ]
Consider the first sample. Overall, the first sample has 3 queries. 1. The first query *l* = 2, *r* = 11 comes. You need to count *f*(2) + *f*(3) + *f*(5) + *f*(7) + *f*(11) = 2 + 1 + 4 + 2 + 0 = 9. 1. The second query comes *l* = 3, *r* = 12. You need to count *f*(3) + *f*(5) + *f*(7) + *f*(11) = 1 + 4 + 2 + 0 = 7....
[ { "input": "6\n5 5 7 10 14 15\n3\n2 11\n3 12\n4 4", "output": "9\n7\n0" }, { "input": "7\n2 3 5 7 11 4 8\n2\n8 10\n2 123", "output": "0\n7" }, { "input": "9\n50 50 50 50 50 50 50 50 50\n7\n20 20\n8 13\n13 13\n6 14\n3 5\n15 17\n341 1792", "output": "0\n0\n0\n0\n9\n0\n0" }, { "...
1,700
264,396,800
0
3,024
554
Ohana Cleans Up
[ "brute force", "greedy", "strings" ]
null
null
Ohana Matsumae is trying to clean a room, which is divided up into an *n* by *n* grid of squares. Each square is initially either clean or dirty. Ohana can sweep her broom over columns of the grid. Her broom is very strange: if she sweeps over a clean square, it will become dirty, and if she sweeps over a dirty square,...
The first line of input will be a single integer *n* (1<=≤<=*n*<=≤<=100). The next *n* lines will describe the state of the room. The *i*-th line will contain a binary string with *n* characters denoting the state of the *i*-th row of the room. The *j*-th character on this line is '1' if the *j*-th square in the *i*-t...
The output should be a single line containing an integer equal to a maximum possible number of rows that are completely clean.
[ "4\n0101\n1000\n1111\n0101\n", "3\n111\n111\n111\n" ]
[ "2\n", "3\n" ]
In the first sample, Ohana can sweep the 1st and 3rd columns. This will make the 1st and 4th row be completely clean. In the second sample, everything is already clean, so Ohana doesn't need to do anything.
[ { "input": "4\n0101\n1000\n1111\n0101", "output": "2" }, { "input": "3\n111\n111\n111", "output": "3" }, { "input": "10\n0100000000\n0000000000\n0000000000\n0000000000\n0000000000\n0000000000\n0000000000\n0000000000\n0000000000\n0000000000", "output": "9" }, { "input": "1\n1"...
46
0
3
3,029
284
Cows and Primitive Roots
[ "implementation", "math", "number theory" ]
null
null
The cows have just learned what a primitive root is! Given a prime *p*, a primitive root is an integer *x* (1<=≤<=*x*<=&lt;<=*p*) such that none of integers *x*<=-<=1,<=*x*2<=-<=1,<=...,<=*x**p*<=-<=2<=-<=1 are divisible by *p*, but *x**p*<=-<=1<=-<=1 is. Unfortunately, computing primitive roots can be time consumin...
The input contains a single line containing an integer *p* (2<=≤<=*p*<=&lt;<=2000). It is guaranteed that *p* is a prime.
Output on a single line the number of primitive roots .
[ "3\n", "5\n" ]
[ "1\n", "2\n" ]
The only primitive root <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/3722298ba062e95b18705d1253eb4e5d31e3b2d1.png" style="max-width: 100.0%;max-height: 100.0%;"/> is 2. The primitive roots <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/1d85c6a17ef1c42b53cf9...
[ { "input": "3", "output": "1" }, { "input": "5", "output": "2" }, { "input": "7", "output": "2" }, { "input": "11", "output": "4" }, { "input": "17", "output": "8" }, { "input": "19", "output": "6" }, { "input": "1583", "output": "672" ...
92
0
0
3,046
913
Too Easy Problems
[ "binary search", "brute force", "data structures", "greedy", "sortings" ]
null
null
You are preparing for an exam on scheduling theory. The exam will last for exactly *T* milliseconds and will consist of *n* problems. You can either solve problem *i* in exactly *t**i* milliseconds or ignore it and spend no time. You don't need time to rest after solving a problem, either. Unfortunately, your teacher ...
The first line contains two integers *n* and *T* (1<=≤<=*n*<=≤<=2·105; 1<=≤<=*T*<=≤<=109) — the number of problems in the exam and the length of the exam in milliseconds, respectively. Each of the next *n* lines contains two integers *a**i* and *t**i* (1<=≤<=*a**i*<=≤<=*n*; 1<=≤<=*t**i*<=≤<=104). The problems are numb...
In the first line, output a single integer *s* — your maximum possible final score. In the second line, output a single integer *k* (0<=≤<=*k*<=≤<=*n*) — the number of problems you should solve. In the third line, output *k* distinct integers *p*1,<=*p*2,<=...,<=*p**k* (1<=≤<=*p**i*<=≤<=*n*) — the indexes of problems...
[ "5 300\n3 100\n4 150\n4 80\n2 90\n2 300\n", "2 100\n1 787\n2 788\n", "2 100\n2 42\n2 58\n" ]
[ "2\n3\n3 1 4\n", "0\n0\n\n", "2\n2\n1 2\n" ]
In the first example, you should solve problems 3, 1, and 4. In this case you'll spend 80 + 100 + 90 = 270 milliseconds, falling within the length of the exam, 300 milliseconds (and even leaving yourself 30 milliseconds to have a rest). Problems 3 and 1 will bring you a point each, while problem 4 won't. You'll score t...
[ { "input": "5 300\n3 100\n4 150\n4 80\n2 90\n2 300", "output": "2\n2\n3 4" }, { "input": "2 100\n1 787\n2 788", "output": "0\n0" }, { "input": "2 100\n2 42\n2 58", "output": "2\n2\n1 2" }, { "input": "1 1\n1 1", "output": "1\n1\n1" }, { "input": "10 481\n4 25\n3 8...
2,000
24,678,400
0
3,060
336
Vasily the Bear and Fly
[ "math" ]
null
null
One beautiful day Vasily the bear painted 2*m* circles of the same radius *R* on a coordinate plane. Circles with numbers from 1 to *m* had centers at points (2*R*<=-<=*R*,<=0), (4*R*<=-<=*R*,<=0), ..., (2*Rm*<=-<=*R*,<=0), respectively. Circles with numbers from *m*<=+<=1 to 2*m* had centers at points (2*R*<=-<=*R*,<=...
The first line contains two integers *m*,<=*R* (1<=≤<=*m*<=≤<=105, 1<=≤<=*R*<=≤<=10).
In a single line print a single real number — the answer to the problem. The answer will be considered correct if its absolute or relative error doesn't exceed 10<=-<=6.
[ "1 1\n", "2 2\n" ]
[ "2.0000000000\n", "5.4142135624\n" ]
<img class="tex-graphics" src="https://espresso.codeforces.com/9fe384073741e20965ddc4bf162afd3a604b6b39.png" style="max-width: 100.0%;max-height: 100.0%;"/> Figure to the second sample
[ { "input": "1 1", "output": "2.0000000000" }, { "input": "2 2", "output": "5.4142135624" }, { "input": "100000 3", "output": "200002.4853316681" }, { "input": "2344 5", "output": "7817.4790439982" }, { "input": "999 10", "output": "6668.3010410807" }, { ...
186
21,811,200
0
3,066
621
Wet Shark and Blocks
[ "dp", "matrices" ]
null
null
There are *b* blocks of digits. Each one consisting of the same *n* digits, which are given to you in the input. Wet Shark must choose exactly one digit from each block and concatenate all of those digits together to form one large integer. For example, if he chooses digit 1 from the first block and digit 2 from the se...
The first line of the input contains four space-separated integers, *n*, *b*, *k* and *x* (2<=≤<=*n*<=≤<=50<=000,<=1<=≤<=*b*<=≤<=109,<=0<=≤<=*k*<=&lt;<=*x*<=≤<=100,<=*x*<=≥<=2) — the number of digits in one block, the number of blocks, interesting remainder modulo *x* and modulo *x* itself. The next line contains *n* ...
Print the number of ways to pick exactly one digit from each blocks, such that the resulting integer equals *k* modulo *x*.
[ "12 1 5 10\n3 5 6 7 8 9 5 1 1 1 1 5\n", "3 2 1 2\n6 2 2\n", "3 2 1 2\n3 1 2\n" ]
[ "3\n", "0\n", "6\n" ]
In the second sample possible integers are 22, 26, 62 and 66. None of them gives the remainder 1 modulo 2. In the third sample integers 11, 13, 21, 23, 31 and 33 have remainder 1 modulo 2. There is exactly one way to obtain each of these integers, so the total answer is 6.
[ { "input": "12 1 5 10\n3 5 6 7 8 9 5 1 1 1 1 5", "output": "3" }, { "input": "3 2 1 2\n6 2 2", "output": "0" }, { "input": "3 2 1 2\n3 1 2", "output": "6" }, { "input": "3 2 1 2\n6 3 2", "output": "3" }, { "input": "3 2 1 2\n3 6 3", "output": "6" }, { ...
0
0
-1
3,077
938
Constructing Tests
[ "binary search", "brute force", "constructive algorithms" ]
null
null
Let's denote a *m*-free matrix as a binary (that is, consisting of only 1's and 0's) matrix such that every square submatrix of size *m*<=×<=*m* of this matrix contains at least one zero. Consider the following problem: You are given two integers *n* and *m*. You have to construct an *m*-free square matrix of size *...
The first line contains one integer *t* (1<=≤<=*t*<=≤<=100) — the number of tests you have to construct. Then *t* lines follow, *i*-th line containing one integer *x**i* (0<=≤<=*x**i*<=≤<=109). Note that in hacks you have to set *t*<==<=1.
For each test you have to construct, output two positive numbers *n**i* and *m**i* (1<=≤<=*m**i*<=≤<=*n**i*<=≤<=109) such that the maximum number of 1's in a *m**i*-free *n**i*<=×<=*n**i* matrix is exactly *x**i*. If there are multiple solutions, you may output any of them; and if this is impossible to construct a test...
[ "3\n21\n0\n1\n" ]
[ "5 2\n1 1\n-1\n" ]
none
[ { "input": "3\n21\n0\n1", "output": "5 2\n1 1\n-1" }, { "input": "1\n420441920", "output": "-1" }, { "input": "1\n4", "output": "-1" }, { "input": "1\n297540", "output": "546 22" }, { "input": "1\n9", "output": "-1" }, { "input": "1\n144", "output"...
1,000
20,377,600
0
3,078
192
Walking in the Rain
[ "brute force", "implementation" ]
null
null
In Berland the opposition is going to arrange mass walking on the boulevard. The boulevard consists of *n* tiles that are lain in a row and are numbered from 1 to *n* from right to left. The opposition should start walking on the tile number 1 and the finish on the tile number *n*. During the walk it is allowed to move...
The first line contains integer *n* (1<=≤<=*n*<=≤<=103) — the boulevard's length in tiles. The second line contains *n* space-separated integers *a**i* — the number of days after which the *i*-th tile gets destroyed (1<=≤<=*a**i*<=≤<=103).
Print a single number — the sought number of days.
[ "4\n10 3 5 10\n", "5\n10 2 8 3 5\n" ]
[ "5\n", "5\n" ]
In the first sample the second tile gets destroyed after day three, and the only path left is 1 → 3 → 4. After day five there is a two-tile gap between the first and the last tile, you can't jump over it. In the second sample path 1 → 3 → 5 is available up to day five, inclusive. On day six the last tile is destroyed ...
[ { "input": "4\n10 3 5 10", "output": "5" }, { "input": "5\n10 2 8 3 5", "output": "5" }, { "input": "10\n10 3 1 6 7 1 3 3 8 1", "output": "1" }, { "input": "10\n26 72 10 52 2 5 61 2 39 64", "output": "5" }, { "input": "100\n8 2 1 2 8 3 5 8 5 1 9 3 4 1 5 6 4 2 9 10...
124
0
3
3,081
723
Text Document Analysis
[ "expression parsing", "implementation", "strings" ]
null
null
Modern text editors usually show some information regarding the document being edited. For example, the number of words, the number of pages, or the number of characters. In this problem you should implement the similar functionality. You are given a string which only consists of: - uppercase and lowercase English ...
The first line of the input contains a single integer *n* (1<=≤<=*n*<=≤<=255) — the length of the given string. The second line contains the string consisting of only lowercase and uppercase English letters, parentheses and underscore symbols.
Print two space-separated integers: - the length of the longest word outside the parentheses (print 0, if there is no word outside the parentheses), - the number of words inside the parentheses (print 0, if there is no word inside the parentheses).
[ "37\n_Hello_Vasya(and_Petya)__bye_(and_OK)\n", "37\n_a_(_b___c)__de_f(g_)__h__i(j_k_l)m__\n", "27\n(LoooonG)__shOrt__(LoooonG)\n", "5\n(___)\n" ]
[ "5 4", "2 6", "5 2", "0 0\n" ]
In the first sample, the words "Hello", "Vasya" and "bye" are outside any of the parentheses, and the words "and", "Petya", "and" and "OK" are inside. Note, that the word "and" is given twice and you should count it twice in the answer.
[ { "input": "37\n_Hello_Vasya(and_Petya)__bye_(and_OK)", "output": "5 4" }, { "input": "37\n_a_(_b___c)__de_f(g_)__h__i(j_k_l)m__", "output": "2 6" }, { "input": "27\n(LoooonG)__shOrt__(LoooonG)", "output": "5 2" }, { "input": "5\n(___)", "output": "0 0" }, { "inpu...
62
0
3
3,085
0
none
[ "none" ]
null
null
Limak is a little polar bear. He doesn't have many toys and thus he often plays with polynomials. He considers a polynomial valid if its degree is *n* and its coefficients are integers not exceeding *k* by the absolute value. More formally: Let *a*0,<=*a*1,<=...,<=*a**n* denote the coefficients, so . Then, a polynomi...
The first line contains two integers *n* and *k* (1<=≤<=*n*<=≤<=200<=000,<=1<=≤<=*k*<=≤<=109) — the degree of the polynomial and the limit for absolute values of coefficients. The second line contains *n*<=+<=1 integers *a*0,<=*a*1,<=...,<=*a**n* (|*a**i*|<=≤<=*k*,<=*a**n*<=≠<=0) — describing a valid polynomial . It's...
Print the number of ways to change one coefficient to get a valid polynomial *Q* that *Q*(2)<==<=0.
[ "3 1000000000\n10 -9 -3 5\n", "3 12\n10 -9 -3 5\n", "2 20\n14 -7 19\n" ]
[ "3\n", "2\n", "0\n" ]
In the first sample, we are given a polynomial *P*(*x*) = 10 - 9*x* - 3*x*<sup class="upper-index">2</sup> + 5*x*<sup class="upper-index">3</sup>. Limak can change one coefficient in three ways: 1. He can set *a*<sub class="lower-index">0</sub> =  - 10. Then he would get *Q*(*x*) =  - 10 - 9*x* - 3*x*<sup class="upp...
[]
30
0
0
3,087
555
Case of Matryoshkas
[ "implementation" ]
null
null
Andrewid the Android is a galaxy-famous detective. He is now investigating the case of vandalism at the exhibition of contemporary art. The main exhibit is a construction of *n* matryoshka dolls that can be nested one into another. The matryoshka dolls are numbered from 1 to *n*. A matryoshka with a smaller number can...
The first line contains integers *n* (1<=≤<=*n*<=≤<=105) and *k* (1<=≤<=*k*<=≤<=105) — the number of matryoshkas and matryoshka chains in the initial configuration. The next *k* lines contain the descriptions of the chains: the *i*-th line first contains number *m**i* (1<=≤<=*m**i*<=≤<=*n*), and then *m**i* numbers *a...
In the single line print the minimum number of seconds needed to assemble one large chain from the initial configuration.
[ "3 2\n2 1 2\n1 3\n", "7 3\n3 1 3 7\n2 2 5\n2 4 6\n" ]
[ "1\n", "10\n" ]
In the first sample test there are two chains: 1 → 2 and 3. In one second you can nest the first chain into the second one and get 1 → 2 → 3. In the second sample test you need to disassemble all the three chains into individual matryoshkas in 2 + 1 + 1 = 4 seconds and then assemble one big chain in 6 seconds.
[ { "input": "3 2\n2 1 2\n1 3", "output": "1" }, { "input": "7 3\n3 1 3 7\n2 2 5\n2 4 6", "output": "10" }, { "input": "1 1\n1 1", "output": "0" }, { "input": "3 2\n1 2\n2 1 3", "output": "3" }, { "input": "5 3\n1 4\n3 1 2 3\n1 5", "output": "2" }, { "in...
46
4,608,000
0
3,090
0
none
[ "none" ]
null
null
An infinitely long railway has a train consisting of *n* cars, numbered from 1 to *n* (the numbers of all the cars are distinct) and positioned in arbitrary order. David Blaine wants to sort the railway cars in the order of increasing numbers. In one move he can make one of the cars disappear from its place and telepor...
The first line of the input contains integer *n* (1<=≤<=*n*<=≤<=100<=000) — the number of cars in the train. The second line contains *n* integers *p**i* (1<=≤<=*p**i*<=≤<=*n*, *p**i*<=≠<=*p**j* if *i*<=≠<=*j*) — the sequence of the numbers of the cars in the train.
Print a single integer — the minimum number of actions needed to sort the railway cars.
[ "5\n4 1 2 5 3\n", "4\n4 1 3 2\n" ]
[ "2\n", "2\n" ]
In the first sample you need first to teleport the 4-th car, and then the 5-th car to the end of the train.
[ { "input": "5\n4 1 2 5 3", "output": "2" }, { "input": "4\n4 1 3 2", "output": "2" }, { "input": "1\n1", "output": "0" }, { "input": "2\n1 2", "output": "0" }, { "input": "2\n2 1", "output": "1" }, { "input": "6\n5 3 6 1 4 2", "output": "4" }, ...
62
0
0
3,095
977
Wrong Subtraction
[ "implementation" ]
null
null
Little girl Tanya is learning how to decrease a number by one, but she does it wrong with a number consisting of two or more digits. Tanya subtracts one from a number by the following algorithm: - if the last digit of the number is non-zero, she decreases the number by one; - if the last digit of the number is zero,...
The first line of the input contains two integer numbers $n$ and $k$ ($2 \le n \le 10^9$, $1 \le k \le 50$) — the number from which Tanya will subtract and the number of subtractions correspondingly.
Print one integer number — the result of the decreasing $n$ by one $k$ times. It is guaranteed that the result will be positive integer number.
[ "512 4\n", "1000000000 9\n" ]
[ "50\n", "1\n" ]
The first example corresponds to the following sequence: $512 \rightarrow 511 \rightarrow 510 \rightarrow 51 \rightarrow 50$.
[ { "input": "512 4", "output": "50" }, { "input": "1000000000 9", "output": "1" }, { "input": "131203 11", "output": "12" }, { "input": "999999999 50", "output": "9999" }, { "input": "999999999 49", "output": "99990" }, { "input": "131203 9", "outpu...
62
0
3
3,096
934
A Prosperous Lot
[ "constructive algorithms", "implementation" ]
null
null
Apart from Nian, there is a daemon named Sui, which terrifies children and causes them to become sick. Parents give their children money wrapped in red packets and put them under the pillow, so that when Sui tries to approach them, it will be driven away by the fairies inside. Big Banban is hesitating over the amount ...
The first and only line contains an integer *k* (1<=≤<=*k*<=≤<=106) — the desired number of loops.
Output an integer — if no such *n* exists, output -1; otherwise output any such *n*. In the latter case, your output should be a positive decimal integer not exceeding 1018.
[ "2\n", "6\n" ]
[ "462", "8080" ]
none
[ { "input": "2", "output": "8" }, { "input": "6", "output": "888" }, { "input": "3", "output": "86" }, { "input": "4", "output": "88" }, { "input": "5", "output": "886" }, { "input": "1000000", "output": "-1" }, { "input": "1", "output":...
77
1,024,000
3
3,114
288
Polo the Penguin and Houses
[ "combinatorics" ]
null
null
Little penguin Polo loves his home village. The village has *n* houses, indexed by integers from 1 to *n*. Each house has a plaque containing an integer, the *i*-th house has a plaque containing integer *p**i* (1<=≤<=*p**i*<=≤<=*n*). Little penguin Polo loves walking around this village. The walk looks like that. Firs...
The single line contains two space-separated integers *n* and *k* (1<=≤<=*n*<=≤<=1000,<=1<=≤<=*k*<=≤<=*min*(8,<=*n*)) — the number of the houses and the number *k* from the statement.
In a single line print a single integer — the answer to the problem modulo 1000000007 (109<=+<=7).
[ "5 2\n", "7 4\n" ]
[ "54\n", "1728\n" ]
none
[ { "input": "5 2", "output": "54" }, { "input": "7 4", "output": "1728" }, { "input": "8 5", "output": "16875" }, { "input": "8 1", "output": "823543" }, { "input": "10 7", "output": "3176523" }, { "input": "12 8", "output": "536870912" }, { ...
31
0
0
3,115
290
HQ
[ "*special", "constructive algorithms" ]
null
null
The famous joke programming language HQ9+ has only 4 commands. In this problem we will explore its subset — a language called HQ...
The only line of the input is a string between 1 and 106 characters long.
Output "Yes" or "No".
[ "HHHH\n", "HQHQH\n", "HHQHHQH\n", "HHQQHHQQHH\n" ]
[ "Yes\n", "No\n", "No\n", "Yes\n" ]
The rest of the problem statement was destroyed by a stray raccoon. We are terribly sorry for the inconvenience.
[ { "input": "HHHH", "output": "Yes" }, { "input": "HQHQH", "output": "No" }, { "input": "HHQHHQH", "output": "No" }, { "input": "HHQQHHQQHH", "output": "Yes" }, { "input": "Q", "output": "Yes" }, { "input": "HHHHHHHHHHQHHH", "output": "No" }, { ...
124
0
0
3,118
739
Alyona and a tree
[ "binary search", "data structures", "dfs and similar", "graphs", "trees" ]
null
null
Alyona has a tree with *n* vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positive integer, in the vertex *i* she wrote *a**i*. Moreover, the girl wrote a positive integer to every edge of the tree (possibly, different integers on different edges). Let's define *dist*(*v*,<=*u*) as the ...
The first line contains single integer *n* (1<=≤<=*n*<=≤<=2·105). The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=109) — the integers written in the vertices. The next (*n*<=-<=1) lines contain two integers each. The *i*-th of these lines contains integers *p**i* and *w**i* (1<=≤<=*...
Print *n* integers — the *i*-th of these numbers should be equal to the number of vertices that the *i*-th vertex controls.
[ "5\n2 5 1 4 6\n1 7\n1 1\n3 5\n3 6\n", "5\n9 7 8 6 5\n1 1\n2 1\n3 1\n4 1\n" ]
[ "1 0 1 0 0\n", "4 3 2 1 0\n" ]
In the example test case the vertex 1 controls the vertex 3, the vertex 3 controls the vertex 5 (note that is doesn't mean the vertex 1 controls the vertex 5).
[ { "input": "5\n2 5 1 4 6\n1 7\n1 1\n3 5\n3 6", "output": "1 0 1 0 0" }, { "input": "5\n9 7 8 6 5\n1 1\n2 1\n3 1\n4 1", "output": "4 3 2 1 0" }, { "input": "1\n1", "output": "0" }, { "input": "2\n1 1\n1 1", "output": "1 0" }, { "input": "10\n40 77 65 14 86 16 2 51 ...
61
0
0
3,121
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 fast...
The first line contains integer *n* (1<=≤<=*n*<=≤<=1000) — 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" }...
31
0
0
3,122
638
Home Numbers
[ "*special", "constructive algorithms", "math" ]
null
null
The main street of Berland is a straight line with *n* houses built along it (*n* is an even number). The houses are located at both sides of the street. The houses with odd numbers are at one side of the street and are numbered from 1 to *n*<=-<=1 in the order from the beginning of the street to the end (in the pictur...
The first line of the input contains two integers, *n* and *a* (1<=≤<=*a*<=≤<=*n*<=≤<=100<=000) — the number of houses on the street and the number of the house that Vasya needs to reach, correspondingly. It is guaranteed that number *n* is even.
Print a single integer — the minimum time Vasya needs to get from the beginning of the street to house *a*.
[ "4 2\n", "8 5\n" ]
[ "2\n", "3\n" ]
In the first sample there are only four houses on the street, two houses at each side. House 2 will be the last at Vasya's right. The second sample corresponds to picture with *n* = 8. House 5 is the one before last at Vasya's left.
[ { "input": "4 2", "output": "2" }, { "input": "8 5", "output": "3" }, { "input": "2 1", "output": "1" }, { "input": "2 2", "output": "1" }, { "input": "10 1", "output": "1" }, { "input": "10 10", "output": "1" }, { "input": "100000 100000",...
62
5,120,000
3
3,129
414
Mashmokh and ACM
[ "combinatorics", "dp", "number theory" ]
null
null
Mashmokh's boss, Bimokh, didn't like Mashmokh. So he fired him. Mashmokh decided to go to university and participate in ACM instead of finding a new job. He wants to become a member of Bamokh's team. In order to join he was given some programming tasks and one week to solve them. Mashmokh is not a very experienced prog...
The first line of input contains two space-separated integers *n*,<=*k* (1<=≤<=*n*,<=*k*<=≤<=2000).
Output a single integer — the number of good sequences of length *k* modulo 1000000007 (109<=+<=7).
[ "3 2\n", "6 4\n", "2 1\n" ]
[ "5\n", "39\n", "2\n" ]
In the first sample the good sequences are: [1, 1], [2, 2], [3, 3], [1, 2], [1, 3].
[ { "input": "3 2", "output": "5" }, { "input": "6 4", "output": "39" }, { "input": "2 1", "output": "2" }, { "input": "1478 194", "output": "312087753" }, { "input": "1415 562", "output": "953558593" }, { "input": "1266 844", "output": "735042656" ...
389
39,936,000
3
3,130
707
Bakery
[ "graphs" ]
null
null
Masha wants to open her own bakery and bake muffins in one of the *n* cities numbered from 1 to *n*. There are *m* bidirectional roads, each of whose connects some pair of cities. To bake muffins in her bakery, Masha needs to establish flour supply from some storage. There are only *k* storages, located in different c...
The first line of the input contains three integers *n*, *m* and *k* (1<=≤<=*n*,<=*m*<=≤<=105, 0<=≤<=*k*<=≤<=*n*) — the number of cities in country Masha lives in, the number of roads between them and the number of flour storages respectively. Then *m* lines follow. Each of them contains three integers *u*, *v* and *l...
Print the minimum possible amount of rubles Masha should pay for flour delivery in the only line. If the bakery can not be opened (while satisfying conditions) in any of the *n* cities, print <=-<=1 in the only line.
[ "5 4 2\n1 2 5\n1 2 3\n2 3 4\n1 4 10\n1 5\n", "3 1 1\n1 2 3\n3\n" ]
[ "3", "-1" ]
Image illustrates the first sample case. Cities with storage located in and the road representing the answer are darkened.
[ { "input": "5 4 2\n1 2 5\n1 2 3\n2 3 4\n1 4 10\n1 5", "output": "3" }, { "input": "3 1 1\n1 2 3\n3", "output": "-1" }, { "input": "2 3 1\n1 2 3\n1 2 18\n1 2 13\n2", "output": "3" }, { "input": "3 7 0\n1 3 9\n1 2 5\n1 2 21\n1 2 12\n1 2 13\n2 3 19\n2 3 8", "output": "-1" ...
327
36,659,200
3
3,131
749
Parallelogram is Back
[ "brute force", "constructive algorithms", "geometry" ]
null
null
Long time ago Alex created an interesting problem about parallelogram. The input data for this problem contained four integer points on the Cartesian plane, that defined the set of vertices of some non-degenerate (positive area) parallelogram. Points not necessary were given in the order of clockwise or counterclockwis...
The input consists of three lines, each containing a pair of integer coordinates *x**i* and *y**i* (<=-<=1000<=≤<=*x**i*,<=*y**i*<=≤<=1000). It's guaranteed that these three points do not lie on the same line and no two of them coincide.
First print integer *k* — the number of ways to add one new integer point such that the obtained set defines some parallelogram of positive area. There is no requirement for the points to be arranged in any special order (like traversal), they just define the set of vertices. Then print *k* lines, each containing a pa...
[ "0 0\n1 0\n0 1\n" ]
[ "3\n1 -1\n-1 1\n1 1\n" ]
If you need clarification of what parallelogram is, please check Wikipedia page: https://en.wikipedia.org/wiki/Parallelogram
[ { "input": "0 0\n1 0\n0 1", "output": "3\n1 -1\n-1 1\n1 1" }, { "input": "0 -1\n-1 0\n1 1", "output": "3\n-2 -2\n2 0\n0 2" }, { "input": "-1 -1\n0 1\n1 1", "output": "3\n-2 -1\n0 -1\n2 3" }, { "input": "1000 1000\n-1000 -1000\n-1000 1000", "output": "3\n1000 -1000\n1000 3...
1,000
2,662,400
0
3,140
127
Canvas Frames
[ "implementation" ]
null
null
Nicholas, a painter is going to paint several new canvases. Nicholas is sure that the canvases will turn out so great that each one will need framing and being hung on the wall. Frames are what Nicholas decided to begin with. Nicholas has *n* sticks whose lengths equal *a*1,<=*a*2,<=... *a**n*. Nicholas does not want...
The first line contains an integer *n* (1<=≤<=*n*<=≤<=100) — the number of sticks. The second line contains *n* space-separated integers. The *i*-th integer equals the length of the *i*-th stick *a**i* (1<=≤<=*a**i*<=≤<=100).
Print the single number — the maximum number of frames Nicholas can make for his future canvases.
[ "5\n2 4 3 2 3\n", "13\n2 2 4 4 4 4 6 6 6 7 7 9 9\n", "4\n3 3 3 5\n" ]
[ "1", "3", "0" ]
none
[ { "input": "5\n2 4 3 2 3", "output": "1" }, { "input": "13\n2 2 4 4 4 4 6 6 6 7 7 9 9", "output": "3" }, { "input": "4\n3 3 3 5", "output": "0" }, { "input": "2\n3 5", "output": "0" }, { "input": "9\n1 2 3 4 5 6 7 8 9", "output": "0" }, { "input": "14\...
77
102,400
3
3,141
65
Harry Potter and the History of Magic
[ "brute force", "greedy", "implementation" ]
B. Harry Potter and the History of Magic
1
256
The History of Magic is perhaps the most boring subject in the Hogwarts school of Witchcraft and Wizardry. Harry Potter is usually asleep during history lessons, and his magical quill writes the lectures for him. Professor Binns, the history of magic teacher, lectures in such a boring and monotonous voice, that he has ...
The first input line contains an integer *n* (1<=≤<=*n*<=≤<=1000). It represents the number of dates in Harry's notes. Next *n* lines contain the actual dates *y*1, *y*2, ..., *y**n*, each line contains a date. Each date is a four-digit integer (1000<=≤<=*y**i*<=≤<=9999).
Print *n* numbers *z*1, *z*2, ..., *z**n* (1000<=≤<=*z**i*<=≤<=2011). They are Ron's resulting dates. Print each number on a single line. Numbers *z**i* must form the non-decreasing sequence. Each number *z**i* should differ from the corresponding date *y**i* in no more than one digit. It is not allowed to change the f...
[ "3\n1875\n1936\n1721\n", "4\n9999\n2000\n3000\n3011\n", "3\n1999\n5055\n2000\n" ]
[ "1835\n1836\n1921\n", "1999\n2000\n2000\n2011\n", "No solution\n" ]
none
[ { "input": "3\n1875\n1936\n1721", "output": "1075\n1136\n1221" }, { "input": "4\n9999\n2000\n3000\n3011", "output": "1999\n2000\n2000\n2011" }, { "input": "3\n1999\n5055\n2000", "output": "No solution" }, { "input": "2\n2037\n2025", "output": "1037\n2005" }, { "in...
124
0
3.938
3,142
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) — 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 c...
Print the only integer *s* — 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...
93
0
0
3,144
788
Functions again
[ "dp", "two pointers" ]
null
null
Something happened in Uzhlyandia again... There are riots on the streets... Famous Uzhlyandian superheroes Shean the Sheep and Stas the Giraffe were called in order to save the situation. Upon the arriving, they found that citizens are worried about maximum values of the Main Uzhlyandian Function *f*, which is defined ...
The first line contains single integer *n* (2<=≤<=*n*<=≤<=105) — the size of the array *a*. The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (-109<=≤<=*a**i*<=≤<=109) — the array elements.
Print the only integer — the maximum value of *f*.
[ "5\n1 4 2 3 1\n", "4\n1 5 4 7\n" ]
[ "3", "6" ]
In the first sample case, the optimal value of *f* is reached on intervals [1, 2] and [2, 5]. In the second case maximal value of *f* is reachable only on the whole array.
[ { "input": "5\n1 4 2 3 1", "output": "3" }, { "input": "4\n1 5 4 7", "output": "6" }, { "input": "8\n16 14 12 10 8 100 50 0", "output": "92" }, { "input": "2\n1 1", "output": "0" }, { "input": "50\n-5 -9 0 44 -10 37 34 -49 11 -22 -26 44 8 -13 23 -46 34 12 -24 2 -4...
296
20,480,000
3
3,145
240
TorCoder
[ "data structures" ]
null
null
A boy named Leo doesn't miss a single TorCoder contest round. On the last TorCoder round number 100666 Leo stumbled over the following problem. He was given a string *s*, consisting of *n* lowercase English letters, and *m* queries. Each query is characterised by a pair of integers *l**i*,<=*r**i* (1<=≤<=*l**i*<=≤<=*r*...
The first input line contains two integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=105) — the string length and the number of the queries. The second line contains string *s*, consisting of *n* lowercase Latin letters. Each of the next *m* lines contains a pair of integers *l**i*,<=*r**i* (1<=≤<=*l**i*<=≤<=*r**i*<=≤<=*n*) —...
In a single line print the result of applying *m* queries to string *s*. Print the queries in the order in which they are given in the input.
[ "7 2\naabcbaa\n1 3\n5 7\n", "3 2\nabc\n1 2\n2 3\n" ]
[ "abacaba\n", "abc\n" ]
A substring (*l*<sub class="lower-index">*i*</sub>, *r*<sub class="lower-index">*i*</sub>) 1 ≤ *l*<sub class="lower-index">*i*</sub> ≤ *r*<sub class="lower-index">*i*</sub> ≤ *n*) of string *s* = *s*<sub class="lower-index">1</sub>*s*<sub class="lower-index">2</sub>... *s*<sub class="lower-index">*n*</sub> of length *n...
[]
30
0
0
3,146
289
Polo the Penguin and Matrix
[ "brute force", "dp", "implementation", "sortings", "ternary search" ]
null
null
Little penguin Polo has an *n*<=×<=*m* matrix, consisting of integers. Let's index the matrix rows from 1 to *n* from top to bottom and let's index the columns from 1 to *m* from left to right. Let's represent the matrix element on the intersection of row *i* and column *j* as *a**ij*. In one move the penguin can add ...
The first line contains three integers *n*, *m* and *d* (1<=≤<=*n*,<=*m*<=≤<=100,<=1<=≤<=*d*<=≤<=104) — the matrix sizes and the *d* parameter. Next *n* lines contain the matrix: the *j*-th integer in the *i*-th row is the matrix element *a**ij* (1<=≤<=*a**ij*<=≤<=104).
In a single line print a single integer — the minimum number of moves the penguin needs to make all matrix elements equal. If that is impossible, print "-1" (without the quotes).
[ "2 2 2\n2 4\n6 8\n", "1 2 7\n6 7\n" ]
[ "4\n", "-1\n" ]
none
[ { "input": "2 2 2\n2 4\n6 8", "output": "4" }, { "input": "1 2 7\n6 7", "output": "-1" }, { "input": "3 2 1\n5 7\n1 2\n5 100", "output": "104" }, { "input": "3 3 3\n5 8 5\n11 11 17\n14 5 2", "output": "12" }, { "input": "3 3 3\n5 8 5\n11 11 17\n14 5 3", "outpu...
124
6,963,200
0
3,147
964
Messages
[ "math" ]
null
null
There are *n* incoming messages for Vasya. The *i*-th message is going to be received after *t**i* minutes. Each message has a cost, which equals to *A* initially. After being received, the cost of a message decreases by *B* each minute (it can become negative). Vasya can read any message after receiving it at any mome...
The first line contains five integers *n*, *A*, *B*, *C* and *T* (1<=≤<=*n*,<=*A*,<=*B*,<=*C*,<=*T*<=≤<=1000). The second string contains *n* integers *t**i* (1<=≤<=*t**i*<=≤<=*T*).
Output one integer  — the answer to the problem.
[ "4 5 5 3 5\n1 5 5 4\n", "5 3 1 1 3\n2 2 2 1 1\n", "5 5 3 4 5\n1 2 3 4 5\n" ]
[ "20\n", "15\n", "35\n" ]
In the first sample the messages must be read immediately after receiving, Vasya receives *A* points for each message, *n*·*A* = 20 in total. In the second sample the messages can be read at any integer moment. In the third sample messages must be read at the moment T. This way Vasya has 1, 2, 3, 4 and 0 unread messa...
[ { "input": "4 5 5 3 5\n1 5 5 4", "output": "20" }, { "input": "5 3 1 1 3\n2 2 2 1 1", "output": "15" }, { "input": "5 5 3 4 5\n1 2 3 4 5", "output": "35" }, { "input": "1 6 4 3 9\n2", "output": "6" }, { "input": "10 9 7 5 3\n3 3 3 3 2 3 2 2 3 3", "output": "90...
139
1,536,000
0
3,161
467
Fedor and New Game
[ "bitmasks", "brute force", "constructive algorithms", "implementation" ]
null
null
After you had helped George and Alex to move in the dorm, they went to help their friend Fedor play a new computer game «Call of Soldiers 3». The game has (*m*<=+<=1) players and *n* types of soldiers in total. Players «Call of Soldiers 3» are numbered form 1 to (*m*<=+<=1). Types of soldiers are numbered from 0 to *n...
The first line contains three integers *n*, *m*, *k* (1<=≤<=*k*<=≤<=*n*<=≤<=20; 1<=≤<=*m*<=≤<=1000). The *i*-th of the next (*m*<=+<=1) lines contains a single integer *x**i* (1<=≤<=*x**i*<=≤<=2*n*<=-<=1), that describes the *i*-th player's army. We remind you that Fedor is the (*m*<=+<=1)-th player.
Print a single integer — the number of Fedor's potential friends.
[ "7 3 1\n8\n5\n111\n17\n", "3 3 3\n1\n2\n3\n4\n" ]
[ "0\n", "3\n" ]
none
[ { "input": "7 3 1\n8\n5\n111\n17", "output": "0" }, { "input": "3 3 3\n1\n2\n3\n4", "output": "3" }, { "input": "4 2 2\n5\n6\n7", "output": "2" }, { "input": "4 7 4\n9\n10\n5\n12\n4\n12\n7\n10", "output": "7" }, { "input": "2 7 2\n1\n1\n1\n1\n1\n1\n1\n1", "out...
62
0
3
3,164
415
Mashmokh and Lights
[ "implementation" ]
null
null
Mashmokh works in a factory. At the end of each day he must turn off all of the lights. The lights on the factory are indexed from 1 to *n*. There are *n* buttons in Mashmokh's room indexed from 1 to *n* as well. If Mashmokh pushes button with index *i*, then each light with index not less than *i* that is still turn...
The first line of the input contains two space-separated integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=100), the number of the factory lights and the pushed buttons respectively. The next line contains *m* distinct space-separated integers *b*1,<=*b*2,<=...,<=*b**m* (1<=≤<=*b**i*<=≤<=*n*). It is guaranteed that all lights...
Output *n* space-separated integers where the *i*-th number is index of the button that turns the *i*-th light off.
[ "5 4\n4 3 1 2\n", "5 5\n5 4 3 2 1\n" ]
[ "1 1 3 4 4 \n", "1 2 3 4 5 \n" ]
In the first sample, after pressing button number 4, lights 4 and 5 are turned off and lights 1, 2 and 3 are still on. Then after pressing button number 3, light number 3 is turned off as well. Pressing button number 1 turns off lights number 1 and 2 as well so pressing button number 2 in the end has no effect. Thus bu...
[ { "input": "5 4\n4 3 1 2", "output": "1 1 3 4 4 " }, { "input": "5 5\n5 4 3 2 1", "output": "1 2 3 4 5 " }, { "input": "16 11\n8 5 12 10 14 2 6 3 15 9 1", "output": "1 2 2 2 5 5 5 8 8 8 8 8 8 8 8 8 " }, { "input": "79 22\n76 32 48 28 33 44 58 59 1 51 77 13 15 64 49 72 74 21 6...
61
0
3
3,169
366
Dima and Salad
[ "dp" ]
null
null
Dima, Inna and Seryozha have gathered in a room. That's right, someone's got to go. To cheer Seryozha up and inspire him to have a walk, Inna decided to cook something. Dima and Seryozha have *n* fruits in the fridge. Each fruit has two parameters: the taste and the number of calories. Inna decided to make a fruit sa...
The first line of the input contains two integers *n*, *k* (1<=≤<=*n*<=≤<=100,<=1<=≤<=*k*<=≤<=10). The second line of the input contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=100) — the fruits' tastes. The third line of the input contains *n* integers *b*1,<=*b*2,<=...,<=*b**n* (1<=≤<=*b**i*<=≤<=100...
If there is no way Inna can choose the fruits for the salad, print in the single line number -1. Otherwise, print a single integer — the maximum possible sum of the taste values of the chosen fruits.
[ "3 2\n10 8 1\n2 7 1\n", "5 3\n4 4 4 4 4\n2 2 2 2 2\n" ]
[ "18\n", "-1\n" ]
In the first test sample we can get the total taste of the fruits equal to 18 if we choose fruit number 1 and fruit number 2, then the total calories will equal 9. The condition <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/f7429bb0084a26268b364ce919a5231a4d9e38a9.png" style="max-width: 1...
[ { "input": "3 2\n10 8 1\n2 7 1", "output": "18" }, { "input": "5 3\n4 4 4 4 4\n2 2 2 2 2", "output": "-1" }, { "input": "1 1\n1\n1", "output": "1" }, { "input": "1 1\n1\n2", "output": "-1" }, { "input": "2 1\n75 65\n16 60", "output": "-1" }, { "input":...
62
2,764,800
-1
3,171
145
Lucky Conversion
[ "greedy", "implementation" ]
null
null
Petya loves lucky numbers very much. Everybody knows that lucky numbers are positive integers whose decimal record contains only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not. Petya has two strings *a* and *b* of the same length *n*. The strings consist only of lucky digits...
The first and the second line contains strings *a* and *b*, correspondingly. Strings *a* and *b* have equal lengths and contain only lucky digits. The strings are not empty, their length does not exceed 105.
Print on the single line the single number — the minimum number of operations needed to convert string *a* into string *b*.
[ "47\n74\n", "774\n744\n", "777\n444\n" ]
[ "1\n", "1\n", "3\n" ]
In the first sample it is enough simply to swap the first and the second digit. In the second sample we should replace the second digit with its opposite. In the third number we should replace all three digits with their opposites.
[ { "input": "47\n74", "output": "1" }, { "input": "774\n744", "output": "1" }, { "input": "777\n444", "output": "3" }, { "input": "74747474\n77777777", "output": "4" }, { "input": "444444444444\n777777777777", "output": "12" }, { "input": "4744744447774...
310
307,200
3
3,172
610
Vika and Squares
[ "constructive algorithms", "implementation" ]
null
null
Vika has *n* jars with paints of distinct colors. All the jars are numbered from 1 to *n* and the *i*-th jar contains *a**i* liters of paint of color *i*. Vika also has an infinitely long rectangular piece of paper of width 1, consisting of squares of size 1<=×<=1. Squares are numbered 1, 2, 3 and so on. Vika decided ...
The first line of the input contains a single integer *n* (1<=≤<=*n*<=≤<=200<=000) — the number of jars with colors Vika has. The second line of the input contains a sequence of integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=109), where *a**i* is equal to the number of liters of paint in the *i*-th jar, i.e. th...
The only line of the output should contain a single integer — the maximum number of squares that Vika can paint if she follows the rules described above.
[ "5\n2 4 2 3 3\n", "3\n5 5 5\n", "6\n10 10 10 1 10 10\n" ]
[ "12\n", "15\n", "11\n" ]
In the first sample the best strategy is to start painting using color 4. Then the squares will be painted in the following colors (from left to right): 4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5. In the second sample Vika can start to paint using any color. In the third sample Vika should start painting using color number 5...
[ { "input": "5\n2 4 2 3 3", "output": "12" }, { "input": "3\n5 5 5", "output": "15" }, { "input": "6\n10 10 10 1 10 10", "output": "11" }, { "input": "1\n167959139", "output": "167959139" }, { "input": "10\n896619242 805194919 844752453 848347723 816995848 85681361...
280
20,172,800
0
3,185
431
Shower Line
[ "brute force", "implementation" ]
null
null
Many students live in a dormitory. A dormitory is a whole new world of funny amusements and possibilities but it does have its drawbacks. There is only one shower and there are multiple students who wish to have a shower in the morning. That's why every morning there is a line of five people in front of the dormitory...
The input consists of five lines, each line contains five space-separated integers: the *j*-th number in the *i*-th line shows *g**ij* (0<=≤<=*g**ij*<=≤<=105). It is guaranteed that *g**ii*<==<=0 for all *i*. Assume that the students are numbered from 1 to 5.
Print a single integer — the maximum possible total happiness of the students.
[ "0 0 0 0 9\n0 0 0 0 0\n0 0 0 0 0\n0 0 0 0 0\n7 0 0 0 0\n", "0 43 21 18 2\n3 0 21 11 65\n5 2 0 1 4\n54 62 12 0 99\n87 64 81 33 0\n" ]
[ "32\n", "620\n" ]
In the first sample, the optimal arrangement of the line is 23154. In this case, the total happiness equals:
[ { "input": "0 0 0 0 9\n0 0 0 0 0\n0 0 0 0 0\n0 0 0 0 0\n7 0 0 0 0", "output": "32" }, { "input": "0 43 21 18 2\n3 0 21 11 65\n5 2 0 1 4\n54 62 12 0 99\n87 64 81 33 0", "output": "620" }, { "input": "0 4 2 4 9\n6 0 2 5 0\n2 5 0 6 3\n6 3 3 0 10\n0 3 1 3 0", "output": "63" }, { ...
77
2,969,600
3
3,199
1,006
Three Parts of the Array
[ "binary search", "data structures", "two pointers" ]
null
null
You are given an array $d_1, d_2, \dots, d_n$ consisting of $n$ integer numbers. Your task is to split this array into three parts (some of which may be empty) in such a way that each element of the array belongs to exactly one of the three parts, and each of the parts forms a consecutive contiguous subsegment (possib...
The first line of the input contains one integer $n$ ($1 \le n \le 2 \cdot 10^5$) — the number of elements in the array $d$. The second line of the input contains $n$ integers $d_1, d_2, \dots, d_n$ ($1 \le d_i \le 10^9$) — the elements of the array $d$.
Print a single integer — the maximum possible value of $sum_1$, considering that the condition $sum_1 = sum_3$ must be met. Obviously, at least one valid way to split the array exists (use $a=c=0$ and $b=n$).
[ "5\n1 3 1 1 4\n", "5\n1 3 2 1 4\n", "3\n4 1 2\n" ]
[ "5\n", "4\n", "0\n" ]
In the first example there is only one possible splitting which maximizes $sum_1$: $[1, 3, 1], [~], [1, 4]$. In the second example the only way to have $sum_1=4$ is: $[1, 3], [2, 1], [4]$. In the third example there is only one way to split the array: $[~], [4, 1, 2], [~]$.
[ { "input": "5\n1 3 1 1 4", "output": "5" }, { "input": "5\n1 3 2 1 4", "output": "4" }, { "input": "3\n4 1 2", "output": "0" }, { "input": "1\n1000000000", "output": "0" }, { "input": "2\n1 1", "output": "1" }, { "input": "5\n1 3 5 4 5", "output": ...
421
34,713,600
3
3,200
844
Rectangles
[ "combinatorics", "math" ]
null
null
You are given *n*<=×<=*m* table. Each cell of the table is colored white or black. Find the number of non-empty sets of cells such that: 1. All cells in a set have the same color. 1. Every two cells in a set share row or column.
The first line of input contains integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=50) — the number of rows and the number of columns correspondingly. The next *n* lines of input contain descriptions of rows. There are *m* integers, separated by spaces, in each line. The number equals 0 if the corresponding cell is colored wh...
Output single integer  — the number of non-empty sets from the problem description.
[ "1 1\n0\n", "2 3\n1 0 1\n0 1 0\n" ]
[ "1\n", "8\n" ]
In the second example, there are six one-element sets. Additionally, there are two two-element sets, the first one consists of the first and the third cells of the first row, the second one consists of the first and the third cells of the second row. To sum up, there are 8 sets.
[ { "input": "1 1\n0", "output": "1" }, { "input": "2 3\n1 0 1\n0 1 0", "output": "8" }, { "input": "2 2\n1 1\n1 1", "output": "8" }, { "input": "1 10\n0 0 0 0 0 0 0 0 0 0", "output": "1023" }, { "input": "11 1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1", "output": "2047"...
62
0
3
3,211
792
Divide by Three
[ "dp", "greedy", "math", "number theory" ]
null
null
A positive integer number *n* is written on a blackboard. It consists of not more than 105 digits. You have to transform it into a beautiful number by erasing some of the digits, and you want to erase as few digits as possible. The number is called beautiful if it consists of at least one digit, doesn't have leading z...
The first line of input contains *n* — a positive integer number without leading zeroes (1<=≤<=*n*<=&lt;<=10100000).
Print one number — any beautiful number obtained by erasing as few as possible digits. If there is no answer, print <=-<=1.
[ "1033\n", "10\n", "11\n" ]
[ "33\n", "0\n", "-1\n" ]
In the first example it is enough to erase only the first digit to obtain a multiple of 3. But if we erase the first digit, then we obtain a number with a leading zero. So the minimum number of digits to be erased is two.
[ { "input": "1033", "output": "33" }, { "input": "10", "output": "0" }, { "input": "11", "output": "-1" }, { "input": "3", "output": "3" }, { "input": "1", "output": "-1" }, { "input": "117", "output": "117" }, { "input": "518", "output"...
124
102,400
0
3,212
292
Copying Data
[ "data structures" ]
null
null
We often have to copy large volumes of information. Such operation can take up many computer resources. Therefore, in this problem you are advised to come up with a way to copy some part of a number array into another one, quickly. More formally, you've got two arrays of integers *a*1,<=*a*2,<=...,<=*a**n* and *b*1,<=...
The first line contains two space-separated integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=105) — the number of elements in the arrays and the number of queries, correspondingly. The second line contains an array of integers *a*1,<=*a*2,<=...,<=*a**n* (|*a**i*|<=≤<=109). The third line contains an array of integers *b*1,<=*...
For each second type query print the result on a single line.
[ "5 10\n1 2 0 -1 3\n3 1 5 -2 0\n2 5\n1 3 3 3\n2 5\n2 4\n2 1\n1 2 1 4\n2 1\n2 4\n1 4 2 1\n2 2\n" ]
[ "0\n3\n-1\n3\n2\n3\n-1\n" ]
none
[ { "input": "5 10\n1 2 0 -1 3\n3 1 5 -2 0\n2 5\n1 3 3 3\n2 5\n2 4\n2 1\n1 2 1 4\n2 1\n2 4\n1 4 2 1\n2 2", "output": "0\n3\n-1\n3\n2\n3\n-1" }, { "input": "1 4\n-2\n1\n1 1 1 1\n2 1\n1 1 1 1\n1 1 1 1", "output": "-2" }, { "input": "2 5\n-3 2\n3 -4\n1 1 1 2\n2 1\n2 1\n1 2 2 1\n2 1", "out...
2,000
7,987,200
0
3,224
755
PolandBall and Forest
[ "dfs and similar", "dsu", "graphs", "interactive", "trees" ]
null
null
PolandBall lives in a forest with his family. There are some trees in the forest. Trees are undirected acyclic graphs with *k* vertices and *k*<=-<=1 edges, where *k* is some integer. Note that one vertex is a valid tree. There is exactly one relative living in each vertex of each tree, they have unique ids from 1 to ...
The first line contains single integer *n* (1<=≤<=*n*<=≤<=104) — the number of Balls living in the forest. The second line contains a sequence *p*1,<=*p*2,<=...,<=*p**n* of length *n*, where (1<=≤<=*p**i*<=≤<=*n*) holds and *p**i* denotes the most distant from Ball *i* relative living on the same tree. If there are se...
You should output the number of trees in the forest where PolandBall lives.
[ "5\n2 1 5 3 3", "1\n1\n" ]
[ "2", "1" ]
In the first sample testcase, possible forest is: 1-2 3-4-5. There are 2 trees overall. In the second sample testcase, the only possible graph is one vertex and no edges. Therefore, there is only one tree.
[ { "input": "5 3\n1 2\n3 4\n4 5", "output": "2" }, { "input": "1 0", "output": "1" }, { "input": "5 1\n4 5", "output": "4" }, { "input": "10 3\n2 8\n5 9\n6 10", "output": "7" }, { "input": "18 2\n9 17\n1 18", "output": "16" }, { "input": "1 0", "out...
93
22,323,200
-1
3,226
103
Cthulhu
[ "dfs and similar", "dsu", "graphs" ]
B. Cthulhu
2
256
...Once upon a time a man came to the sea. The sea was stormy and dark. The man started to call for the little mermaid to appear but alas, he only woke up Cthulhu... Whereas on the other end of the world Pentagon is actively collecting information trying to predict the monster's behavior and preparing the secret super...
The first line contains two integers — the number of vertices *n* and the number of edges *m* of the graph (1<=≤<=*n*<=≤<=100, 0<=≤<=*m*<=≤<=). Each of the following *m* lines contains a pair of integers *x* and *y*, that show that an edge exists between vertices *x* and *y* (1<=≤<=*x*,<=*y*<=≤<=*n*,<=*x*<=≠<=*y*). Fo...
Print "NO", if the graph is not Cthulhu and "FHTAGN!" if it is.
[ "6 6\n6 3\n6 4\n5 1\n2 5\n1 4\n5 4\n", "6 5\n5 6\n4 6\n3 1\n5 1\n1 2\n" ]
[ "FHTAGN!", "NO" ]
Let us denote as a simple cycle a set of *v* vertices that can be numbered so that the edges will only exist between vertices number 1 and 2, 2 and 3, ..., *v* - 1 and *v*, *v* and 1. A tree is a connected undirected graph consisting of *n* vertices and *n* - 1 edges (*n* &gt; 0). A rooted tree is a tree where one ve...
[ { "input": "6 6\n6 3\n6 4\n5 1\n2 5\n1 4\n5 4", "output": "FHTAGN!" }, { "input": "6 5\n5 6\n4 6\n3 1\n5 1\n1 2", "output": "NO" }, { "input": "10 10\n4 10\n8 5\n2 8\n4 9\n9 3\n2 7\n10 6\n10 2\n9 8\n1 8", "output": "FHTAGN!" }, { "input": "5 4\n1 5\n1 3\n1 4\n3 2", "outpu...
186
6,656,000
0
3,227
990
Bracket Sequences Concatenation Problem
[ "implementation" ]
null
null
A bracket sequence is a string containing only characters "(" and ")". A regular bracket sequence is a bracket sequence that can be transformed into a correct arithmetic expression by inserting characters "1" and "+" between the original characters of the sequence. For example, bracket sequences "()()", "(())" are reg...
The first line contains one integer $n \, (1 \le n \le 3 \cdot 10^5)$ — the number of bracket sequences. The following $n$ lines contain bracket sequences — non-empty strings consisting only of characters "(" and ")". The sum of lengths of all bracket sequences does not exceed $3 \cdot 10^5$.
In the single line print a single integer — the number of pairs $i, j \, (1 \le i, j \le n)$ such that the bracket sequence $s_i + s_j$ is a regular bracket sequence.
[ "3\n)\n()\n(\n", "2\n()\n()\n" ]
[ "2\n", "4\n" ]
In the first example, suitable pairs are $(3, 1)$ and $(2, 2)$. In the second example, any pair is suitable, namely $(1, 1), (1, 2), (2, 1), (2, 2)$.
[ { "input": "3\n)\n()\n(", "output": "2" }, { "input": "2\n()\n()", "output": "4" }, { "input": "7\n()(\n)\n)(\n())\n(((\n()()()\n()", "output": "6" }, { "input": "6\n(\n((\n(((\n))))\n)))))\n))))))", "output": "0" }, { "input": "9\n(()\n((())\n(\n)\n(()()(()())))\...
2,000
5,324,800
0
3,228
837
Round Subset
[ "dp", "math" ]
null
null
Let's call the roundness of the number the number of zeros to which it ends. You have an array of *n* numbers. You need to choose a subset of exactly *k* numbers so that the roundness of the product of the selected numbers will be maximum possible.
The first line contains two integer numbers *n* and *k* (1<=≤<=*n*<=≤<=200,<=1<=≤<=*k*<=≤<=*n*). The second line contains *n* space-separated integer numbers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=1018).
Print maximal roundness of product of the chosen subset of length *k*.
[ "3 2\n50 4 20\n", "5 3\n15 16 3 25 9\n", "3 3\n9 77 13\n" ]
[ "3\n", "3\n", "0\n" ]
In the first example there are 3 subsets of 2 numbers. [50, 4] has product 200 with roundness 2, [4, 20] — product 80, roundness 1, [50, 20] — product 1000, roundness 3. In the second example subset [15, 16, 25] has product 6000, roundness 3. In the third example all subsets has product with roundness 0.
[ { "input": "3 2\n50 4 20", "output": "3" }, { "input": "5 3\n15 16 3 25 9", "output": "3" }, { "input": "3 3\n9 77 13", "output": "0" }, { "input": "1 1\n200000000", "output": "8" }, { "input": "1 1\n3", "output": "0" }, { "input": "3 1\n10000000000000...
30
0
0
3,234
533
Work Group
[ "dfs and similar", "dp", "graphs", "strings", "trees" ]
null
null
One Big Software Company has *n* employees numbered from 1 to *n*. The director is assigned number 1. Every employee of the company except the director has exactly one immediate superior. The director, of course, doesn't have a superior. We will call person *a* a subordinates of another person *b*, if either *b* is an...
The first line contains integer *n* (1<=≤<=*n*<=≤<=2·105) — the number of workers of the Big Software Company. Then *n* lines follow, describing the company employees. The *i*-th line contains two integers *p**i*,<=*a**i* (1<=≤<=*a**i*<=≤<=105) — the number of the person who is the *i*-th employee's immediate superio...
Print a single integer — the maximum possible efficiency of the workgroup.
[ "7\n-1 3\n1 2\n1 1\n1 4\n4 5\n4 3\n5 2\n" ]
[ "17\n" ]
In the sample test the most effective way is to make a workgroup from employees number 1, 2, 4, 5, 6.
[ { "input": "7\n-1 3\n1 2\n1 1\n1 4\n4 5\n4 3\n5 2", "output": "17" }, { "input": "1\n-1 42", "output": "42" }, { "input": "2\n-1 3\n1 2", "output": "3" }, { "input": "3\n-1 3\n1 1\n1 2", "output": "6" }, { "input": "3\n-1 1\n1 2\n1 3", "output": "6" }, { ...
0
0
-1
3,247
919
Perfect Number
[ "binary search", "brute force", "dp", "implementation", "number theory" ]
null
null
We consider a positive integer perfect, if and only if the sum of its digits is exactly $10$. Given a positive integer $k$, your task is to find the $k$-th smallest perfect positive integer.
A single line with a positive integer $k$ ($1 \leq k \leq 10\,000$).
A single number, denoting the $k$-th smallest perfect integer.
[ "1\n", "2\n" ]
[ "19\n", "28\n" ]
The first perfect integer is $19$ and the second one is $28$.
[ { "input": "1", "output": "19" }, { "input": "2", "output": "28" }, { "input": "13", "output": "136" }, { "input": "101", "output": "1432" }, { "input": "1023", "output": "100270" }, { "input": "9999", "output": "10800010" }, { "input": "10...
186
1,740,800
3
3,262
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 opera...
The first line of the input contains a single integer *n* (1<=≤<=*n*<=≤<=3000) — 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...
140
204,800
3
3,270
701
They Are Everywhere
[ "binary search", "strings", "two pointers" ]
null
null
Sergei B., the young coach of Pokemons, has found the big house which consists of *n* flats ordered in a row from left to right. It is possible to enter each flat from the street. It is possible to go out from each flat. Also, each flat is connected with the flat to the left and the flat to the right. Flat number 1 is ...
The first line contains the integer *n* (1<=≤<=*n*<=≤<=100<=000) — the number of flats in the house. The second line contains the row *s* with the length *n*, it consists of uppercase and lowercase letters of English alphabet, the *i*-th letter equals the type of Pokemon, which is in the flat number *i*.
Print the minimum number of flats which Sergei B. should visit in order to catch Pokemons of all types which there are in the house.
[ "3\nAaA\n", "7\nbcAAcbc\n", "6\naaBCCe\n" ]
[ "2\n", "3\n", "5\n" ]
In the first test Sergei B. can begin, for example, from the flat number 1 and end in the flat number 2. In the second test Sergei B. can begin, for example, from the flat number 4 and end in the flat number 6. In the third test Sergei B. must begin from the flat number 2 and end in the flat number 6.
[ { "input": "3\nAaA", "output": "2" }, { "input": "7\nbcAAcbc", "output": "3" }, { "input": "6\naaBCCe", "output": "5" }, { "input": "1\nA", "output": "1" }, { "input": "1\ng", "output": "1" }, { "input": "52\nabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQ...
171
4,710,400
3
3,278
44
Cola
[ "implementation" ]
B. Cola
2
256
To celebrate the opening of the Winter Computer School the organizers decided to buy in *n* liters of cola. However, an unexpected difficulty occurred in the shop: it turned out that cola is sold in bottles 0.5, 1 and 2 liters in volume. At that, there are exactly *a* bottles 0.5 in volume, *b* one-liter bottles and *c...
The first line contains four integers — *n*, *a*, *b*, *c* (1<=≤<=*n*<=≤<=10000, 0<=≤<=*a*,<=*b*,<=*c*<=≤<=5000).
Print the unique number — the solution to the problem. If it is impossible to buy exactly *n* liters of cola, print 0.
[ "10 5 5 5\n", "3 0 0 2\n" ]
[ "9\n", "0\n" ]
none
[ { "input": "10 5 5 5", "output": "9" }, { "input": "3 0 0 2", "output": "0" }, { "input": "1 0 0 0", "output": "0" }, { "input": "1 1 0 0", "output": "0" }, { "input": "1 2 0 0", "output": "1" }, { "input": "1 0 1 0", "output": "1" }, { "in...
746
2,252,800
3.809304
3,300
413
Spyke Chatting
[ "implementation" ]
null
null
The R2 company has *n* employees working for it. The work involves constant exchange of ideas, sharing the stories of success and upcoming challenging. For that, R2 uses a famous instant messaging program Spyke. R2 has *m* Spyke chats just to discuss all sorts of issues. In each chat, some group of employees exchanges...
The first line contains three space-separated integers *n*, *m* and *k* (2<=≤<=*n*<=≤<=2·104; 1<=≤<=*m*<=≤<=10; 1<=≤<=*k*<=≤<=2·105) — the number of the employees, the number of chats and the number of events in the log, correspondingly. Next *n* lines contain matrix *a* of size *n*<=×<=*m*, consisting of numbers zer...
Print in the single line *n* space-separated integers, where the *i*-th integer shows the number of message notifications the *i*-th employee receives.
[ "3 4 5\n1 1 1 1\n1 0 1 1\n1 1 0 0\n1 1\n3 1\n1 3\n2 4\n3 2\n", "4 3 4\n0 1 1\n1 0 1\n1 1 1\n0 0 0\n1 2\n2 1\n3 1\n1 3\n" ]
[ "3 3 1 ", "0 2 3 0 " ]
none
[ { "input": "3 4 5\n1 1 1 1\n1 0 1 1\n1 1 0 0\n1 1\n3 1\n1 3\n2 4\n3 2", "output": "3 3 1 " }, { "input": "4 3 4\n0 1 1\n1 0 1\n1 1 1\n0 0 0\n1 2\n2 1\n3 1\n1 3", "output": "0 2 3 0 " }, { "input": "2 1 1\n1\n1\n1 1", "output": "0 1 " }, { "input": "3 3 1\n1 1 1\n1 1 1\n1 1 1\...
1,000
15,052,800
0
3,303
841
Godsend
[ "games", "math" ]
null
null
Leha somehow found an array consisting of *n* integers. Looking at it, he came up with a task. Two players play the game on the array. Players move one by one. The first player can choose for his move a subsegment of non-zero length with an odd sum of numbers and remove it from the array, after that the remaining parts...
First line of input data contains single integer *n* (1<=≤<=*n*<=≤<=106) — length of the array. Next line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (0<=≤<=*a**i*<=≤<=109).
Output answer in single line. "First", if first player wins, and "Second" otherwise (without quotes).
[ "4\n1 3 2 3\n", "2\n2 2\n" ]
[ "First\n", "Second\n" ]
In first sample first player remove whole array in one move and win. In second sample first player can't make a move and lose.
[ { "input": "4\n1 3 2 3", "output": "First" }, { "input": "2\n2 2", "output": "Second" }, { "input": "4\n2 4 6 8", "output": "Second" }, { "input": "5\n1 1 1 1 1", "output": "First" }, { "input": "4\n720074544 345031254 849487632 80870826", "output": "Second" ...
467
57,446,400
3
3,311
995
Leaving the Bar
[ "brute force", "data structures", "geometry", "greedy", "math", "sortings" ]
null
null
For a vector $\vec{v} = (x, y)$, define $|v| = \sqrt{x^2 + y^2}$. Allen had a bit too much to drink at the bar, which is at the origin. There are $n$ vectors $\vec{v_1}, \vec{v_2}, \cdots, \vec{v_n}$. Allen will make $n$ moves. As Allen's sense of direction is impaired, during the $i$-th move he will either move in th...
The first line contains a single integer $n$ ($1 \le n \le 10^5$) — the number of moves. Each of the following lines contains two space-separated integers $x_i$ and $y_i$, meaning that $\vec{v_i} = (x_i, y_i)$. We have that $|v_i| \le 10^6$ for all $i$.
Output a single line containing $n$ integers $c_1, c_2, \cdots, c_n$, each of which is either $1$ or $-1$. Your solution is correct if the value of $p = \sum_{i = 1}^n c_i \vec{v_i}$, satisfies $|p| \le 1.5 \cdot 10^6$. It can be shown that a solution always exists under the given constraints.
[ "3\n999999 0\n0 999999\n999999 0\n", "1\n-824590 246031\n", "8\n-67761 603277\n640586 -396671\n46147 -122580\n569609 -2112\n400 914208\n131792 309779\n-850150 -486293\n5272 721899\n" ]
[ "1 1 -1 \n", "1 \n", "1 1 1 1 1 1 1 -1 \n" ]
none
[ { "input": "3\n999999 0\n0 999999\n999999 0", "output": "1 1 -1 " }, { "input": "1\n-824590 246031", "output": "1 " }, { "input": "8\n-67761 603277\n640586 -396671\n46147 -122580\n569609 -2112\n400 914208\n131792 309779\n-850150 -486293\n5272 721899", "output": "1 1 1 1 1 1 1 -1 " ...
1,154
15,872,000
0
3,319
38
Blinds
[ "brute force" ]
C. Blinds
2
256
The blinds are known to consist of opaque horizontal stripes that can be rotated thus regulating the amount of light flowing in the room. There are *n* blind stripes with the width of 1 in the factory warehouse for blind production. The problem is that all of them are spare details from different orders, that is, they ...
The first output line contains two space-separated integers *n* and *l* (1<=≤<=*n*,<=*l*<=≤<=100). They are the number of stripes in the warehouse and the minimal acceptable length of a blind stripe in bourlemeters. The second line contains space-separated *n* integers *a**i*. They are the lengths of initial stripes in...
Print the single number — the maximal area of the window in square bourlemeters that can be completely covered. If no window with a positive area that can be covered completely without breaking any of the given rules exist, then print the single number 0.
[ "4 2\n1 2 3 4\n", "5 3\n5 5 7 3 1\n", "2 3\n1 2\n" ]
[ "8\n", "15\n", "0\n" ]
In the first sample test the required window is 2 × 4 in size and the blinds for it consist of 4 parts, each 2 bourlemeters long. One of the parts is the initial stripe with the length of 2, the other one is a part of a cut stripe with the length of 3 and the two remaining stripes are parts of a stripe with the length ...
[ { "input": "4 2\n1 2 3 4", "output": "8" }, { "input": "5 3\n5 5 7 3 1", "output": "15" }, { "input": "2 3\n1 2", "output": "0" }, { "input": "2 2\n3 3", "output": "6" }, { "input": "5 2\n2 4 1 1 3", "output": "8" }, { "input": "7 4\n3 2 1 1 1 3 2", ...
124
0
0
3,325
493
Vasya and Wrestling
[ "implementation" ]
null
null
Vasya has become interested in wrestling. In wrestling wrestlers use techniques for which they are awarded points by judges. The wrestler who gets the most points wins. When the numbers of points of both wrestlers are equal, the wrestler whose sequence of points is lexicographically greater, wins. If the sequences of...
The first line contains number *n* — the number of techniques that the wrestlers have used (1<=≤<=*n*<=≤<=2·105). The following *n* lines contain integer numbers *a**i* (|*a**i*|<=≤<=109, *a**i*<=≠<=0). If *a**i* is positive, that means that the first wrestler performed the technique that was awarded with *a**i* poin...
If the first wrestler wins, print string "first", otherwise print "second"
[ "5\n1\n2\n-3\n-4\n3\n", "3\n-1\n-2\n3\n", "2\n4\n-4\n" ]
[ "second\n", "first\n", "second\n" ]
Sequence *x*  =  *x*<sub class="lower-index">1</sub>*x*<sub class="lower-index">2</sub>... *x*<sub class="lower-index">|*x*|</sub> is lexicographically larger than sequence *y*  =  *y*<sub class="lower-index">1</sub>*y*<sub class="lower-index">2</sub>... *y*<sub class="lower-index">|*y*|</sub>, if either |*x*|  &gt;  |...
[ { "input": "5\n1\n2\n-3\n-4\n3", "output": "second" }, { "input": "3\n-1\n-2\n3", "output": "first" }, { "input": "2\n4\n-4", "output": "second" }, { "input": "7\n1\n2\n-3\n4\n5\n-6\n7", "output": "first" }, { "input": "14\n1\n2\n3\n4\n5\n6\n7\n-8\n-9\n-10\n-11\n-...
390
6,144,000
0
3,326
431
k-Tree
[ "dp", "implementation", "trees" ]
null
null
Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and came up with the tree of his own which he called a *k*-tree. A *k*-tree is an infinite rooted tree where: - each vertex has exactly *k* children; - each edge has some weight; - if we look at the edges that goes...
A single line contains three space-separated integers: *n*, *k* and *d* (1<=≤<=*n*,<=*k*<=≤<=100; 1<=≤<=*d*<=≤<=*k*).
Print a single integer — the answer to the problem modulo 1000000007 (109<=+<=7).
[ "3 3 2\n", "3 3 3\n", "4 3 2\n", "4 5 2\n" ]
[ "3\n", "1\n", "6\n", "7\n" ]
none
[ { "input": "3 3 2", "output": "3" }, { "input": "3 3 3", "output": "1" }, { "input": "4 3 2", "output": "6" }, { "input": "4 5 2", "output": "7" }, { "input": "28 6 3", "output": "110682188" }, { "input": "5 100 1", "output": "16" }, { "inp...
31
0
0
3,330
913
Power Substring
[ "math", "number theory" ]
null
null
You are given *n* positive integers *a*1,<=*a*2,<=...,<=*a**n*. For every *a**i* you need to find a positive integer *k**i* such that the decimal notation of 2*k**i* contains the decimal notation of *a**i* as a substring among its last *min*(100,<=*length*(2*k**i*)) digits. Here *length*(*m*) is the length of the deci...
The first line contains a single integer *n* (1<=≤<=*n*<=≤<=2<=000) — the number of integers *a**i*. Each of the next *n* lines contains a positive integer *a**i* (1<=≤<=*a**i*<=&lt;<=1011).
Print *n* lines. The *i*-th of them should contain a positive integer *k**i* such that the last *min*(100,<=*length*(2*k**i*)) digits of 2*k**i* contain the decimal notation of *a**i* as a substring. Integers *k**i* must satisfy 1<=≤<=*k**i*<=≤<=1050. It can be shown that the answer always exists under the given const...
[ "2\n8\n2\n", "2\n3\n4857\n" ]
[ "3\n1\n", "5\n20\n" ]
none
[ { "input": "2\n8\n2", "output": "3\n1" }, { "input": "2\n3\n4857", "output": "5\n20" }, { "input": "7\n1\n7\n9\n5\n6\n10\n4", "output": "9\n17\n13\n21\n4\n42\n2" }, { "input": "10\n384\n179\n982\n466\n646\n226\n759\n798\n291\n852", "output": "14\n493\n230\n150\n66\n2050\n...
140
7,168,000
3
3,335
485
Valuable Resources
[ "brute force", "greedy" ]
null
null
Many computer strategy games require building cities, recruiting army, conquering tribes, collecting resources. Sometimes it leads to interesting problems. Let's suppose that your task is to build a square city. The world map uses the Cartesian coordinates. The sides of the city should be parallel to coordinate axes....
The first line of the input contains number *n* — the number of mines on the map (2<=≤<=*n*<=≤<=1000). Each of the next *n* lines contains a pair of integers *x**i* and *y**i* — the coordinates of the corresponding mine (<=-<=109<=≤<=*x**i*,<=*y**i*<=≤<=109). All points are pairwise distinct.
Print the minimum area of the city that can cover all the mines with valuable resources.
[ "2\n0 0\n2 2\n", "2\n0 0\n0 3\n" ]
[ "4\n", "9\n" ]
none
[ { "input": "2\n0 0\n2 2", "output": "4" }, { "input": "2\n0 0\n0 3", "output": "9" }, { "input": "2\n0 1\n1 0", "output": "1" }, { "input": "3\n2 2\n1 1\n3 3", "output": "4" }, { "input": "3\n3 1\n1 3\n2 2", "output": "4" }, { "input": "3\n0 1\n1 0\n2 ...
46
0
0
3,344
548
Mike and Fun
[ "brute force", "dp", "greedy", "implementation" ]
null
null
Mike and some bears are playing a game just for fun. Mike is the judge. All bears except Mike are standing in an *n*<=×<=*m* grid, there's exactly one bear in each cell. We denote the bear standing in column number *j* of row number *i* by (*i*,<=*j*). Mike's hands are on his ears (since he's the judge) and each bear s...
The first line of input contains three integers *n*, *m* and *q* (1<=≤<=*n*,<=*m*<=≤<=500 and 1<=≤<=*q*<=≤<=5000). The next *n* lines contain the grid description. There are *m* integers separated by spaces in each line. Each of these numbers is either 0 (for mouth) or 1 (for eyes). The next *q* lines contain the inf...
After each round, print the current score of the bears.
[ "5 4 5\n0 1 1 0\n1 0 0 1\n0 1 1 0\n1 0 0 1\n0 0 0 0\n1 1\n1 4\n1 1\n4 2\n4 3\n" ]
[ "3\n4\n3\n3\n4\n" ]
none
[ { "input": "5 4 5\n0 1 1 0\n1 0 0 1\n0 1 1 0\n1 0 0 1\n0 0 0 0\n1 1\n1 4\n1 1\n4 2\n4 3", "output": "3\n4\n3\n3\n4" }, { "input": "2 2 10\n1 1\n0 1\n1 1\n2 1\n1 1\n2 2\n1 1\n2 1\n2 2\n2 2\n1 1\n1 1", "output": "1\n2\n2\n2\n1\n1\n1\n1\n2\n1" }, { "input": "2 2 10\n1 1\n0 1\n2 2\n2 2\n1 1\...
686
15,155,200
3
3,347