contestId int64 0 1.01k | name stringlengths 2 58 | tags listlengths 0 11 | title stringclasses 523
values | time-limit stringclasses 8
values | memory-limit stringclasses 8
values | problem-description stringlengths 0 7.15k | input-specification stringlengths 0 2.05k | output-specification stringlengths 0 1.5k | demo-input listlengths 0 7 | demo-output listlengths 0 7 | note stringlengths 0 5.24k | test_cases listlengths 0 402 | timeConsumedMillis int64 0 8k | memoryConsumedBytes int64 0 537M | score float64 -1 3.99 | __index_level_0__ int64 0 621k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
343 | Alternating Current | [
"data structures",
"greedy",
"implementation"
] | null | null | Mad scientist Mike has just finished constructing a new device to search for extraterrestrial intelligence! He was in such a hurry to launch it for the first time that he plugged in the power wires without giving it a proper glance and started experimenting right away. After a while Mike observed that the wires ended up entangled and now have to be untangled again.
The device is powered by two wires "plus" and "minus". The wires run along the floor from the wall (on the left) to the device (on the right). Both the wall and the device have two contacts in them on the same level, into which the wires are plugged in some order. The wires are considered entangled if there are one or more places where one wire runs above the other one. For example, the picture below has four such places (top view):
Mike knows the sequence in which the wires run above each other. Mike also noticed that on the left side, the "plus" wire is always plugged into the top contact (as seen on the picture). He would like to untangle the wires without unplugging them and without moving the device. Determine if it is possible to do that. A wire can be freely moved and stretched on the floor, but cannot be cut.
To understand the problem better please read the notes to the test samples. | The single line of the input contains a sequence of characters "+" and "-" of length *n* (1<=≤<=*n*<=≤<=100000). The *i*-th (1<=≤<=*i*<=≤<=*n*) position of the sequence contains the character "+", if on the *i*-th step from the wall the "plus" wire runs above the "minus" wire, and the character "-" otherwise. | Print either "Yes" (without the quotes) if the wires can be untangled or "No" (without the quotes) if the wires cannot be untangled. | [
"-++-\n",
"+-\n",
"++\n",
"-\n"
] | [
"Yes\n",
"No\n",
"Yes\n",
"No\n"
] | The first testcase corresponds to the picture in the statement. To untangle the wires, one can first move the "plus" wire lower, thus eliminating the two crosses in the middle, and then draw it under the "minus" wire, eliminating also the remaining two crosses.
In the second testcase the "plus" wire makes one full revolution around the "minus" wire. Thus the wires cannot be untangled:
In the third testcase the "plus" wire simply runs above the "minus" wire twice in sequence. The wires can be untangled by lifting "plus" and moving it higher:
In the fourth testcase the "minus" wire runs above the "plus" wire once. The wires cannot be untangled without moving the device itself: | [
{
"input": "-++-",
"output": "Yes"
},
{
"input": "+-",
"output": "No"
},
{
"input": "++",
"output": "Yes"
},
{
"input": "-",
"output": "No"
},
{
"input": "+-+-",
"output": "No"
},
{
"input": "-+-",
"output": "No"
},
{
"input": "-++-+--+",
... | 278 | 716,800 | 0 | 1,148 | |
0 | none | [
"none"
] | null | null | Santa Claus is the first who came to the Christmas Olympiad, and he is going to be the first to take his place at a desk! In the classroom there are *n* lanes of *m* desks each, and there are two working places at each of the desks. The lanes are numbered from 1 to *n* from the left to the right, the desks in a lane are numbered from 1 to *m* starting from the blackboard. Note that the lanes go perpendicularly to the blackboard, not along it (see picture).
The organizers numbered all the working places from 1 to 2*nm*. The places are numbered by lanes (i. e. all the places of the first lane go first, then all the places of the second lane, and so on), in a lane the places are numbered starting from the nearest to the blackboard (i. e. from the first desk in the lane), at each desk, the place on the left is numbered before the place on the right.
Santa Clause knows that his place has number *k*. Help him to determine at which lane at which desk he should sit, and whether his place is on the left or on the right! | The only line contains three integers *n*, *m* and *k* (1<=≤<=*n*,<=*m*<=≤<=10<=000, 1<=≤<=*k*<=≤<=2*nm*) — the number of lanes, the number of desks in each lane and the number of Santa Claus' place. | Print two integers: the number of lane *r*, the number of desk *d*, and a character *s*, which stands for the side of the desk Santa Claus. The character *s* should be "L", if Santa Clause should sit on the left, and "R" if his place is on the right. | [
"4 3 9\n",
"4 3 24\n",
"2 4 4\n"
] | [
"2 2 L\n",
"4 3 R\n",
"1 2 R\n"
] | The first and the second samples are shown on the picture. The green place corresponds to Santa Claus' place in the first example, the blue place corresponds to Santa Claus' place in the second example.
In the third sample there are two lanes with four desks in each, and Santa Claus has the fourth place. Thus, his place is in the first lane at the second desk on the right. | [
{
"input": "4 3 9",
"output": "2 2 L"
},
{
"input": "4 3 24",
"output": "4 3 R"
},
{
"input": "2 4 4",
"output": "1 2 R"
},
{
"input": "3 10 24",
"output": "2 2 R"
},
{
"input": "10 3 59",
"output": "10 3 L"
},
{
"input": "10000 10000 160845880",
"... | 77 | 4,608,000 | 3 | 1,151 | |
348 | Mafia | [
"binary search",
"math",
"sortings"
] | null | null | One day *n* friends gathered together to play "Mafia". During each round of the game some player must be the supervisor and other *n*<=-<=1 people take part in the game. For each person we know in how many rounds he wants to be a player, not the supervisor: the *i*-th person wants to play *a**i* rounds. What is the minimum number of rounds of the "Mafia" game they need to play to let each person play at least as many rounds as they want? | The first line contains integer *n* (3<=≤<=*n*<=≤<=105). The second line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=109) — the *i*-th number in the list is the number of rounds the *i*-th person wants to play. | In a single line print a single integer — the minimum number of game rounds the friends need to let the *i*-th person play at least *a**i* rounds.
Please, do not use the %lld specifier to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specifier. | [
"3\n3 2 2\n",
"4\n2 2 2 2\n"
] | [
"4\n",
"3\n"
] | You don't need to know the rules of "Mafia" to solve this problem. If you're curious, it's a game Russia got from the Soviet times: http://en.wikipedia.org/wiki/Mafia_(party_game). | [
{
"input": "3\n3 2 2",
"output": "4"
},
{
"input": "4\n2 2 2 2",
"output": "3"
},
{
"input": "7\n9 7 7 8 8 7 8",
"output": "9"
},
{
"input": "10\n13 12 10 13 13 14 10 10 12 12",
"output": "14"
},
{
"input": "10\n94 96 91 95 99 94 96 92 95 99",
"output": "106"
... | 216 | 15,872,000 | 3 | 1,153 | |
628 | Tennis Tournament | [
"implementation",
"math"
] | null | null | A tennis tournament with *n* participants is running. The participants are playing by an olympic system, so the winners move on and the losers drop out.
The tournament takes place in the following way (below, *m* is the number of the participants of the current round):
- let *k* be the maximal power of the number 2 such that *k*<=≤<=*m*, - *k* participants compete in the current round and a half of them passes to the next round, the other *m*<=-<=*k* participants pass to the next round directly, - when only one participant remains, the tournament finishes.
Each match requires *b* bottles of water for each participant and one bottle for the judge. Besides *p* towels are given to each participant for the whole tournament.
Find the number of bottles and towels needed for the tournament.
Note that it's a tennis tournament so in each match two participants compete (one of them will win and the other will lose). | The only line contains three integers *n*,<=*b*,<=*p* (1<=≤<=*n*,<=*b*,<=*p*<=≤<=500) — the number of participants and the parameters described in the problem statement. | Print two integers *x* and *y* — the number of bottles and towels need for the tournament. | [
"5 2 3\n",
"8 2 4\n"
] | [
"20 15\n",
"35 32\n"
] | In the first example will be three rounds:
1. in the first round will be two matches and for each match 5 bottles of water are needed (two for each of the participants and one for the judge), 1. in the second round will be only one match, so we need another 5 bottles of water, 1. in the third round will also be only one match, so we need another 5 bottles of water.
So in total we need 20 bottles of water.
In the second example no participant will move on to some round directly. | [
{
"input": "5 2 3",
"output": "20 15"
},
{
"input": "8 2 4",
"output": "35 32"
},
{
"input": "10 1 500",
"output": "27 5000"
},
{
"input": "20 500 1",
"output": "19019 20"
},
{
"input": "100 123 99",
"output": "24453 9900"
},
{
"input": "500 1 1",
... | 140 | 0 | 0 | 1,156 | |
359 | Table | [
"constructive algorithms",
"greedy",
"implementation"
] | null | null | Simon has a rectangular table consisting of *n* rows and *m* columns. Simon numbered the rows of the table from top to bottom starting from one and the columns — from left to right starting from one. We'll represent the cell on the *x*-th row and the *y*-th column as a pair of numbers (*x*,<=*y*). The table corners are cells: (1,<=1), (*n*,<=1), (1,<=*m*), (*n*,<=*m*).
Simon thinks that some cells in this table are good. Besides, it's known that no good cell is the corner of the table.
Initially, all cells of the table are colorless. Simon wants to color all cells of his table. In one move, he can choose any good cell of table (*x*1,<=*y*1), an arbitrary corner of the table (*x*2,<=*y*2) and color all cells of the table (*p*,<=*q*), which meet both inequations: *min*(*x*1,<=*x*2)<=≤<=*p*<=≤<=*max*(*x*1,<=*x*2), *min*(*y*1,<=*y*2)<=≤<=*q*<=≤<=*max*(*y*1,<=*y*2).
Help Simon! Find the minimum number of operations needed to color all cells of the table. Note that you can color one cell multiple times. | The first line contains exactly two integers *n*, *m* (3<=≤<=*n*,<=*m*<=≤<=50).
Next *n* lines contain the description of the table cells. Specifically, the *i*-th line contains *m* space-separated integers *a**i*1,<=*a**i*2,<=...,<=*a**im*. If *a**ij* equals zero, then cell (*i*,<=*j*) isn't good. Otherwise *a**ij* equals one. It is guaranteed that at least one cell is good. It is guaranteed that no good cell is a corner. | Print a single number — the minimum number of operations Simon needs to carry out his idea. | [
"3 3\n0 0 0\n0 1 0\n0 0 0\n",
"4 3\n0 0 0\n0 0 1\n1 0 0\n0 0 0\n"
] | [
"4\n",
"2\n"
] | In the first sample, the sequence of operations can be like this:
- For the first time you need to choose cell (2, 2) and corner (1, 1). - For the second time you need to choose cell (2, 2) and corner (3, 3). - For the third time you need to choose cell (2, 2) and corner (3, 1). - For the fourth time you need to choose cell (2, 2) and corner (1, 3).
In the second sample the sequence of operations can be like this:
- For the first time you need to choose cell (3, 1) and corner (4, 3). - For the second time you need to choose cell (2, 3) and corner (1, 1). | [
{
"input": "3 3\n0 0 0\n0 1 0\n0 0 0",
"output": "4"
},
{
"input": "4 3\n0 0 0\n0 0 1\n1 0 0\n0 0 0",
"output": "2"
},
{
"input": "50 4\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 1 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0\n0 0 0 0... | 61 | 3,072,000 | -1 | 1,161 | |
600 | Extract Numbers | [
"implementation",
"strings"
] | null | null | You are given string *s*. Let's call word any largest sequence of consecutive symbols without symbols ',' (comma) and ';' (semicolon). For example, there are four words in string "aba,123;1a;0": "aba", "123", "1a", "0". A word can be empty: for example, the string *s*=";;" contains three empty words separated by ';'.
You should find all words in the given string that are nonnegative INTEGER numbers without leading zeroes and build by them new string *a*. String *a* should contain all words that are numbers separating them by ',' (the order of numbers should remain the same as in the string *s*). By all other words you should build string *b* in the same way (the order of numbers should remain the same as in the string *s*).
Here strings "101", "0" are INTEGER numbers, but "01" and "1.0" are not.
For example, for the string aba,123;1a;0 the string *a* would be equal to "123,0" and string *b* would be equal to "aba,1a". | The only line of input contains the string *s* (1<=≤<=|*s*|<=≤<=105). The string contains only symbols '.' (ASCII 46), ',' (ASCII 44), ';' (ASCII 59), digits, lowercase and uppercase latin letters. | Print the string *a* to the first line and string *b* to the second line. Each string should be surrounded by quotes (ASCII 34).
If there are no words that are numbers print dash (ASCII 45) on the first line. If all words are numbers print dash on the second line. | [
"aba,123;1a;0\n",
"1;;01,a0,\n",
"1\n",
"a\n"
] | [
"\"123,0\"\n\"aba,1a\"\n",
"\"1\"\n\",01,a0,\"\n",
"\"1\"\n-\n",
"-\n\"a\"\n"
] | In the second example the string *s* contains five words: "1", "", "01", "a0", "". | [
{
"input": "aba,123;1a;0",
"output": "\"123,0\"\n\"aba,1a\""
},
{
"input": "1;;01,a0,",
"output": "\"1\"\n\",01,a0,\""
},
{
"input": "1",
"output": "\"1\"\n-"
},
{
"input": "a",
"output": "-\n\"a\""
},
{
"input": ",;,,;",
"output": "-\n\",,,,,\""
},
{
... | 77 | 0 | 0 | 1,163 | |
136 | Presents | [
"implementation"
] | null | null | Little Petya very much likes gifts. Recently he has received a new laptop as a New Year gift from his mother. He immediately decided to give it to somebody else as what can be more pleasant than giving somebody gifts. And on this occasion he organized a New Year party at his place and invited *n* his friends there.
If there's one thing Petya likes more that receiving gifts, that's watching others giving gifts to somebody else. Thus, he safely hid the laptop until the next New Year and made up his mind to watch his friends exchanging gifts while he does not participate in the process. He numbered all his friends with integers from 1 to *n*. Petya remembered that a friend number *i* gave a gift to a friend number *p**i*. He also remembered that each of his friends received exactly one gift.
Now Petya wants to know for each friend *i* the number of a friend who has given him a gift. | The first line contains one integer *n* (1<=≤<=*n*<=≤<=100) — the quantity of friends Petya invited to the party. The second line contains *n* space-separated integers: the *i*-th number is *p**i* — the number of a friend who gave a gift to friend number *i*. It is guaranteed that each friend received exactly one gift. It is possible that some friends do not share Petya's ideas of giving gifts to somebody else. Those friends gave the gifts to themselves. | Print *n* space-separated integers: the *i*-th number should equal the number of the friend who gave a gift to friend number *i*. | [
"4\n2 3 4 1\n",
"3\n1 3 2\n",
"2\n1 2\n"
] | [
"4 1 2 3\n",
"1 3 2\n",
"1 2\n"
] | none | [
{
"input": "4\n2 3 4 1",
"output": "4 1 2 3"
},
{
"input": "3\n1 3 2",
"output": "1 3 2"
},
{
"input": "2\n1 2",
"output": "1 2"
},
{
"input": "1\n1",
"output": "1"
},
{
"input": "10\n1 3 2 6 4 5 7 9 8 10",
"output": "1 3 2 5 6 4 7 9 8 10"
},
{
"input"... | 60 | 0 | -1 | 1,165 | |
125 | Measuring Lengths in Baden | [
"math"
] | null | null | Lengths are measures in Baden in inches and feet. To a length from centimeters it is enough to know that an inch equals three centimeters in Baden and one foot contains 12 inches.
You are given a length equal to *n* centimeters. Your task is to convert it to feet and inches so that the number of feet was maximum. The result should be an integer rounded to the closest value containing an integral number of inches.
Note that when you round up, 1 cm rounds up to 0 inches and 2 cm round up to 1 inch. | The only line contains an integer *n* (1<=≤<=*n*<=≤<=10000). | Print two non-negative space-separated integers *a* and *b*, where *a* is the numbers of feet and *b* is the number of inches. | [
"42\n",
"5\n"
] | [
"1 2\n",
"0 2\n"
] | none | [
{
"input": "42",
"output": "1 2"
},
{
"input": "5",
"output": "0 2"
},
{
"input": "24",
"output": "0 8"
},
{
"input": "1",
"output": "0 0"
},
{
"input": "2",
"output": "0 1"
},
{
"input": "3",
"output": "0 1"
},
{
"input": "4",
"output"... | 216 | 6,656,000 | 3 | 1,166 | |
472 | Design Tutorial: Learn from Math | [
"math",
"number theory"
] | null | null | One way to create a task is to learn from math. You can generate some random math statement or modify some theorems to get something new and build a new task from that.
For example, there is a statement called the "Goldbach's conjecture". It says: "each even number no less than four can be expressed as the sum of two primes". Let's modify it. How about a statement like that: "each integer no less than 12 can be expressed as the sum of two composite numbers." Not like the Goldbach's conjecture, I can prove this theorem.
You are given an integer *n* no less than 12, express it as a sum of two composite numbers. | The only line contains an integer *n* (12<=≤<=*n*<=≤<=106). | Output two composite integers *x* and *y* (1<=<<=*x*,<=*y*<=<<=*n*) such that *x*<=+<=*y*<==<=*n*. If there are multiple solutions, you can output any of them. | [
"12\n",
"15\n",
"23\n",
"1000000\n"
] | [
"4 8\n",
"6 9\n",
"8 15\n",
"500000 500000\n"
] | In the first example, 12 = 4 + 8 and both 4, 8 are composite numbers. You can output "6 6" or "8 4" as well.
In the second example, 15 = 6 + 9. Note that you can't output "1 14" because 1 is not a composite number. | [
{
"input": "12",
"output": "4 8"
},
{
"input": "15",
"output": "6 9"
},
{
"input": "23",
"output": "8 15"
},
{
"input": "1000000",
"output": "500000 500000"
},
{
"input": "63874",
"output": "4 63870"
},
{
"input": "14568",
"output": "4 14564"
},
... | 1,000 | 1,331,200 | 0 | 1,168 | |
363 | Soroban | [
"implementation"
] | null | null | You know that Japan is the country with almost the largest 'electronic devices per person' ratio. So you might be quite surprised to find out that the primary school in Japan teaches to count using a Soroban — an abacus developed in Japan. This phenomenon has its reasons, of course, but we are not going to speak about them. Let's have a look at the Soroban's construction.
Soroban consists of some number of rods, each rod contains five beads. We will assume that the rods are horizontal lines. One bead on each rod (the leftmost one) is divided from the others by a bar (the reckoning bar). This single bead is called go-dama and four others are ichi-damas. Each rod is responsible for representing a single digit from 0 to 9. We can obtain the value of a digit by following simple algorithm:
- Set the value of a digit equal to 0. - If the go-dama is shifted to the right, add 5. - Add the number of ichi-damas shifted to the left.
Thus, the upper rod on the picture shows digit 0, the middle one shows digit 2 and the lower one shows 7. We will consider the top rod to represent the last decimal digit of a number, so the picture shows number 720.
Write the program that prints the way Soroban shows the given number *n*. | The first line contains a single integer *n* (0<=≤<=*n*<=<<=109). | Print the description of the decimal digits of number *n* from the last one to the first one (as mentioned on the picture in the statement), one per line. Print the beads as large English letters 'O', rod pieces as character '-' and the reckoning bar as '|'. Print as many rods, as many digits are in the decimal representation of number *n* without leading zeroes. We can assume that number 0 has no leading zeroes. | [
"2\n",
"13\n",
"720\n"
] | [
"O-|OO-OO\n",
"O-|OOO-O\nO-|O-OOO\n",
"O-|-OOOO\nO-|OO-OO\n-O|OO-OO\n"
] | none | [
{
"input": "2",
"output": "O-|OO-OO"
},
{
"input": "13",
"output": "O-|OOO-O\nO-|O-OOO"
},
{
"input": "720",
"output": "O-|-OOOO\nO-|OO-OO\n-O|OO-OO"
},
{
"input": "0",
"output": "O-|-OOOO"
},
{
"input": "1",
"output": "O-|O-OOO"
},
{
"input": "3",
... | 46 | 0 | 0 | 1,169 | |
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 reach huge size it is recommended to use fast input/output methods: for example, prefer to use scanf/printf instead of cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java. Don't use the function input() in Python2 instead of it use the function raw_input(). | 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 "<" if *a*<=<<=*b* and the symbol ">" if *a*<=><=*b*. If the numbers are equal print the symbol "=". | [
"9\n10\n",
"11\n10\n",
"00012345\n12345\n",
"0123\n9\n",
"0123\n111\n"
] | [
"<\n",
">\n",
"=\n",
">\n",
">\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 | 3,276,800 | 0 | 1,178 | |
252 | Little Xor | [
"brute force",
"implementation"
] | null | null | Little Petya likes arrays that consist of non-negative integers a lot. Recently his mom has presented him one such array consisting of *n* elements. Petya immediately decided to find there a segment of consecutive elements, such that the *xor* of all numbers from this segment was maximal possible. Help him with that.
The *xor* operation is the bitwise exclusive "OR", that is denoted as "xor" in Pascal and "^" in C/C++/Java. | The first line contains integer *n* (1<=≤<=*n*<=≤<=100) — the number of elements in the array. The second line contains the space-separated integers from the array. All numbers are non-negative integers strictly less than 230. | Print a single integer — the required maximal *xor* of a segment of consecutive elements. | [
"5\n1 2 1 1 2\n",
"3\n1 2 7\n",
"4\n4 2 4 8\n"
] | [
"3\n",
"7\n",
"14\n"
] | In the first sample one of the optimal segments is the segment that consists of the first and the second array elements, if we consider the array elements indexed starting from one.
The second sample contains only one optimal segment, which contains exactly one array element (element with index three). | [
{
"input": "5\n1 2 1 1 2",
"output": "3"
},
{
"input": "3\n1 2 7",
"output": "7"
},
{
"input": "4\n4 2 4 8",
"output": "14"
},
{
"input": "5\n1 1 1 1 1",
"output": "1"
},
{
"input": "16\n0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15",
"output": "15"
},
{
"inpu... | 154 | 7,475,200 | 0 | 1,179 | |
11 | A Simple Task | [
"bitmasks",
"dp",
"graphs"
] | D. A Simple Task | 2 | 256 | Given a simple graph, output the number of simple cycles in it. A simple cycle is a cycle with no repeated vertices or edges. | The first line of input contains two integers *n* and *m* (1<=≤<=*n*<=≤<=19, 0<=≤<=*m*) – respectively the number of vertices and edges of the graph. Each of the subsequent *m* lines contains two integers *a* and *b*, (1<=≤<=*a*,<=*b*<=≤<=*n*, *a*<=≠<=*b*) indicating that vertices *a* and *b* are connected by an undirected edge. There is no more than one edge connecting any pair of vertices. | Output the number of cycles in the given graph. | [
"4 6\n1 2\n1 3\n1 4\n2 3\n2 4\n3 4\n"
] | [
"7\n"
] | The example graph is a clique and contains four cycles of length 3 and three cycles of length 4. | [
{
"input": "4 6\n1 2\n1 3\n1 4\n2 3\n2 4\n3 4",
"output": "7"
},
{
"input": "10 3\n4 8\n9 4\n8 9",
"output": "1"
},
{
"input": "8 28\n1 2\n1 3\n1 4\n1 5\n1 6\n1 7\n1 8\n2 3\n2 4\n2 5\n2 6\n2 7\n2 8\n3 4\n3 5\n3 6\n3 7\n3 8\n4 5\n4 6\n4 7\n4 8\n5 6\n5 7\n5 8\n6 7\n6 8\n7 8",
"output":... | 30 | 0 | 0 | 1,180 |
980 | Marlin | [
"constructive algorithms"
] | null | null | The city of Fishtopia can be imagined as a grid of $4$ rows and an odd number of columns. It has two main villages; the first is located at the top-left cell $(1,1)$, people who stay there love fishing at the Tuna pond at the bottom-right cell $(4, n)$. The second village is located at $(4, 1)$ and its people love the Salmon pond at $(1, n)$.
The mayor of Fishtopia wants to place $k$ hotels in the city, each one occupying one cell. To allow people to enter the city from anywhere, hotels should not be placed on the border cells.
A person can move from one cell to another if those cells are not occupied by hotels and share a side.
Can you help the mayor place the hotels in a way such that there are equal number of shortest paths from each village to its preferred pond? | The first line of input contain two integers, $n$ and $k$ ($3 \leq n \leq 99$, $0 \leq k \leq 2\times(n-2)$), $n$ is odd, the width of the city, and the number of hotels to be placed, respectively. | Print "YES", if it is possible to place all the hotels in a way that satisfies the problem statement, otherwise print "NO".
If it is possible, print an extra $4$ lines that describe the city, each line should have $n$ characters, each of which is "#" if that cell has a hotel on it, or "." if not. | [
"7 2\n",
"5 3\n"
] | [
"YES\n.......\n.#.....\n.#.....\n.......\n",
"YES\n.....\n.###.\n.....\n.....\n"
] | none | [
{
"input": "7 2",
"output": "YES\n.......\n.#.....\n.#.....\n......."
},
{
"input": "5 3",
"output": "YES\n.....\n.###.\n.....\n....."
},
{
"input": "3 2",
"output": "YES\n...\n.#.\n.#.\n..."
},
{
"input": "3 0",
"output": "YES\n...\n...\n...\n..."
},
{
"input": "... | 78 | 7,065,600 | 0 | 1,183 | |
855 | Tom Riddle's Diary | [
"brute force",
"implementation",
"strings"
] | null | null | Harry Potter is on a mission to destroy You-Know-Who's Horcruxes. The first Horcrux that he encountered in the Chamber of Secrets is Tom Riddle's diary. The diary was with Ginny and it forced her to open the Chamber of Secrets. Harry wants to know the different people who had ever possessed the diary to make sure they are not under its influence.
He has names of *n* people who possessed the diary in order. You need to tell, for each person, if he/she possessed the diary at some point before or not.
Formally, for a name *s**i* in the *i*-th line, output "YES" (without quotes) if there exists an index *j* such that *s**i*<==<=*s**j* and *j*<=<<=*i*, otherwise, output "NO" (without quotes). | First line of input contains an integer *n* (1<=≤<=*n*<=≤<=100) — the number of names in the list.
Next *n* lines each contain a string *s**i*, consisting of lowercase English letters. The length of each string is between 1 and 100. | Output *n* lines each containing either "YES" or "NO" (without quotes), depending on whether this string was already present in the stream or not.
You can print each letter in any case (upper or lower). | [
"6\ntom\nlucius\nginny\nharry\nginny\nharry\n",
"3\na\na\na\n"
] | [
"NO\nNO\nNO\nNO\nYES\nYES\n",
"NO\nYES\nYES\n"
] | In test case 1, for *i* = 5 there exists *j* = 3 such that *s*<sub class="lower-index">*i*</sub> = *s*<sub class="lower-index">*j*</sub> and *j* < *i*, which means that answer for *i* = 5 is "YES". | [
{
"input": "6\ntom\nlucius\nginny\nharry\nginny\nharry",
"output": "NO\nNO\nNO\nNO\nYES\nYES"
},
{
"input": "3\na\na\na",
"output": "NO\nYES\nYES"
},
{
"input": "1\nzn",
"output": "NO"
},
{
"input": "9\nliyzmbjwnzryjokufuxcqtzwworjeoxkbaqrujrhdidqdvwdfzilwszgnzglnnbogaclckfnb... | 124 | 0 | 3 | 1,186 | |
409 | A + B Strikes Back | [
"*special",
"brute force",
"constructive algorithms",
"dsu",
"implementation"
] | null | null | A + B is often used as an example of the easiest problem possible to show some contest platform. However, some scientists have observed that sometimes this problem is not so easy to get accepted. Want to try? | The input contains two integers *a* and *b* (0<=≤<=*a*,<=*b*<=≤<=103), separated by a single space. | Output the sum of the given integers. | [
"5 14\n",
"381 492\n"
] | [
"19\n",
"873\n"
] | none | [
{
"input": "5 14",
"output": "19"
},
{
"input": "381 492",
"output": "873"
},
{
"input": "536 298",
"output": "834"
},
{
"input": "143 522",
"output": "665"
},
{
"input": "433 126",
"output": "559"
},
{
"input": "723 350",
"output": "1073"
},
{... | 30 | 0 | -1 | 1,191 | |
902 | Coloring a Tree | [
"dfs and similar",
"dsu",
"greedy"
] | null | null | You are given a rooted tree with *n* vertices. The vertices are numbered from 1 to *n*, the root is the vertex number 1.
Each vertex has a color, let's denote the color of vertex *v* by *c**v*. Initially *c**v*<==<=0.
You have to color the tree into the given colors using the smallest possible number of steps. On each step you can choose a vertex *v* and a color *x*, and then color all vectices in the subtree of *v* (including *v* itself) in color *x*. In other words, for every vertex *u*, such that the path from root to *u* passes through *v*, set *c**u*<==<=*x*.
It is guaranteed that you have to color each vertex in a color different from 0.
You can learn what a rooted tree is using the link: [https://en.wikipedia.org/wiki/Tree_(graph_theory)](https://en.wikipedia.org/wiki/Tree_(graph_theory)). | The first line contains a single integer *n* (2<=≤<=*n*<=≤<=104) — the number of vertices in the tree.
The second line contains *n*<=-<=1 integers *p*2,<=*p*3,<=...,<=*p**n* (1<=≤<=*p**i*<=<<=*i*), where *p**i* means that there is an edge between vertices *i* and *p**i*.
The third line contains *n* integers *c*1,<=*c*2,<=...,<=*c**n* (1<=≤<=*c**i*<=≤<=*n*), where *c**i* is the color you should color the *i*-th vertex into.
It is guaranteed that the given graph is a tree. | Print a single integer — the minimum number of steps you have to perform to color the tree into given colors. | [
"6\n1 2 2 1 5\n2 1 1 1 1 1\n",
"7\n1 1 2 3 1 4\n3 3 1 1 1 2 3\n"
] | [
"3\n",
"5\n"
] | The tree from the first sample is shown on the picture (numbers are vetices' indices):
<img class="tex-graphics" src="https://espresso.codeforces.com/10324ccdc37f95343acc4f3c6050d8c334334ffa.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On first step we color all vertices in the subtree of vertex 1 into color 2 (numbers are colors):
<img class="tex-graphics" src="https://espresso.codeforces.com/1c7bb267e2c1a006132248a43121400189309e2f.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On seond step we color all vertices in the subtree of vertex 5 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/2201a6d49b89ba850ff0d0bdcbb3f8e9dd3871a8.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On third step we color all vertices in the subtree of vertex 2 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/6fa977fcdebdde94c47695151e0427b33d0102c5.png" style="max-width: 100.0%;max-height: 100.0%;"/>
The tree from the second sample is shown on the picture (numbers are vetices' indices):
<img class="tex-graphics" src="https://espresso.codeforces.com/d70f9ae72a2ed429dd6531cac757e375dd3c953d.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On first step we color all vertices in the subtree of vertex 1 into color 3 (numbers are colors):
<img class="tex-graphics" src="https://espresso.codeforces.com/7289e8895d0dd56c47b6b17969b9cf77b36786b5.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On second step we color all vertices in the subtree of vertex 3 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/819001df7229138db3a407713744d1e3be88b64e.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On third step we color all vertices in the subtree of vertex 6 into color 2:
<img class="tex-graphics" src="https://espresso.codeforces.com/80ebbd870a0a339636a21b9acdaf9de046458b43.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On fourth step we color all vertices in the subtree of vertex 4 into color 1:
<img class="tex-graphics" src="https://espresso.codeforces.com/ed836aa723ac0176abde4e32988e3ac205014e93.png" style="max-width: 100.0%;max-height: 100.0%;"/>
On fith step we color all vertices in the subtree of vertex 7 into color 3:
<img class="tex-graphics" src="https://espresso.codeforces.com/8132909e11b41c27b8df2f0b0c10bc841f35e58a.png" style="max-width: 100.0%;max-height: 100.0%;"/> | [
{
"input": "6\n1 2 2 1 5\n2 1 1 1 1 1",
"output": "3"
},
{
"input": "7\n1 1 2 3 1 4\n3 3 1 1 1 2 3",
"output": "5"
},
{
"input": "2\n1\n2 2",
"output": "1"
},
{
"input": "3\n1 1\n2 2 2",
"output": "1"
},
{
"input": "4\n1 2 1\n1 2 3 4",
"output": "4"
},
{
... | 92 | 6,963,200 | 3 | 1,193 | |
92 | Binary Number | [
"greedy"
] | B. Binary Number | 1 | 256 | Little walrus Fangy loves math very much. That's why when he is bored he plays with a number performing some operations.
Fangy takes some positive integer *x* and wants to get a number one from it. While *x* is not equal to 1, Fangy repeats the following action: if *x* is odd, then he adds 1 to it, otherwise he divides *x* by 2. Fangy knows that for any positive integer number the process ends in finite time.
How many actions should Fangy perform to get a number one from number *x*? | The first line contains a positive integer *x* in a binary system. It is guaranteed that the first digit of *x* is different from a zero and the number of its digits does not exceed 106. | Print the required number of actions. | [
"1\n",
"1001001\n",
"101110\n"
] | [
"0\n",
"12\n",
"8\n"
] | Let's consider the third sample. Number 101110 is even, which means that we should divide it by 2. After the dividing Fangy gets an odd number 10111 and adds one to it. Number 11000 can be divided by 2 three times in a row and get number 11. All that's left is to increase the number by one (we get 100), and then divide it by 2 two times in a row. As a result, we get 1. | [
{
"input": "1",
"output": "0"
},
{
"input": "1001001",
"output": "12"
},
{
"input": "101110",
"output": "8"
},
{
"input": "11",
"output": "3"
},
{
"input": "11110001101",
"output": "16"
},
{
"input": "101010100100111100011111001111100001010101111110101... | 1,000 | 4,300,800 | 0 | 1,194 |
0 | none | [
"none"
] | null | null | Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular *w* mm <=×<= *h* mm sheet of glass, a diamond glass cutter and lots of enthusiasm. What he lacks is understanding of what to carve and how.
In order not to waste time, he decided to practice the technique of carving. To do this, he makes vertical and horizontal cuts through the entire sheet. This process results in making smaller rectangular fragments of glass. Leonid does not move the newly made glass fragments. In particular, a cut divides each fragment of glass that it goes through into smaller fragments.
After each cut Leonid tries to determine what area the largest of the currently available glass fragments has. Since there appear more and more fragments, this question takes him more and more time and distracts him from the fascinating process.
Leonid offers to divide the labor — he will cut glass, and you will calculate the area of the maximum fragment after each cut. Do you agree? | The first line contains three integers *w*,<=*h*,<=*n* (2<=≤<=*w*,<=*h*<=≤<=200<=000, 1<=≤<=*n*<=≤<=200<=000).
Next *n* lines contain the descriptions of the cuts. Each description has the form *H* *y* or *V* *x*. In the first case Leonid makes the horizontal cut at the distance *y* millimeters (1<=≤<=*y*<=≤<=*h*<=-<=1) from the lower edge of the original sheet of glass. In the second case Leonid makes a vertical cut at distance *x* (1<=≤<=*x*<=≤<=*w*<=-<=1) millimeters from the left edge of the original sheet of glass. It is guaranteed that Leonid won't make two identical cuts. | After each cut print on a single line the area of the maximum available glass fragment in mm2. | [
"4 3 4\nH 2\nV 2\nV 3\nV 1\n",
"7 6 5\nH 4\nV 3\nV 5\nH 2\nV 1\n"
] | [
"8\n4\n4\n2\n",
"28\n16\n12\n6\n4\n"
] | Picture for the first sample test: | [
{
"input": "4 3 4\nH 2\nV 2\nV 3\nV 1",
"output": "8\n4\n4\n2"
},
{
"input": "7 6 5\nH 4\nV 3\nV 5\nH 2\nV 1",
"output": "28\n16\n12\n6\n4"
},
{
"input": "2 2 1\nV 1",
"output": "2"
},
{
"input": "2 2 1\nH 1",
"output": "2"
},
{
"input": "2 2 2\nV 1\nH 1",
"ou... | 46 | 0 | 0 | 1,195 | |
741 | Arpa's weak amphitheater and Mehrdad's valuable Hoses | [
"dfs and similar",
"dp",
"dsu"
] | null | null | Just to remind, girls in Arpa's land are really nice.
Mehrdad wants to invite some Hoses to the palace for a dancing party. Each Hos has some weight *w**i* and some beauty *b**i*. Also each Hos may have some friends. Hoses are divided in some friendship groups. Two Hoses *x* and *y* are in the same friendship group if and only if there is a sequence of Hoses *a*1,<=*a*2,<=...,<=*a**k* such that *a**i* and *a**i*<=+<=1 are friends for each 1<=≤<=*i*<=<<=*k*, and *a*1<==<=*x* and *a**k*<==<=*y*.
Arpa allowed to use the amphitheater of palace to Mehrdad for this party. Arpa's amphitheater can hold at most *w* weight on it.
Mehrdad is so greedy that he wants to invite some Hoses such that sum of their weights is not greater than *w* and sum of their beauties is as large as possible. Along with that, from each friendship group he can either invite all Hoses, or no more than one. Otherwise, some Hoses will be hurt. Find for Mehrdad the maximum possible total beauty of Hoses he can invite so that no one gets hurt and the total weight doesn't exceed *w*. | The first line contains integers *n*, *m* and *w* (1<=<=≤<=<=*n*<=<=≤<=<=1000, , 1<=≤<=*w*<=≤<=1000) — the number of Hoses, the number of pair of friends and the maximum total weight of those who are invited.
The second line contains *n* integers *w*1,<=*w*2,<=...,<=*w**n* (1<=≤<=*w**i*<=≤<=1000) — the weights of the Hoses.
The third line contains *n* integers *b*1,<=*b*2,<=...,<=*b**n* (1<=≤<=*b**i*<=≤<=106) — the beauties of the Hoses.
The next *m* lines contain pairs of friends, the *i*-th of them contains two integers *x**i* and *y**i* (1<=≤<=*x**i*,<=*y**i*<=≤<=*n*, *x**i*<=≠<=*y**i*), meaning that Hoses *x**i* and *y**i* are friends. Note that friendship is bidirectional. All pairs (*x**i*,<=*y**i*) are distinct. | Print the maximum possible total beauty of Hoses Mehrdad can invite so that no one gets hurt and the total weight doesn't exceed *w*. | [
"3 1 5\n3 2 5\n2 4 2\n1 2\n",
"4 2 11\n2 4 6 6\n6 4 2 1\n1 2\n2 3\n"
] | [
"6\n",
"7\n"
] | In the first sample there are two friendship groups: Hoses {1, 2} and Hos {3}. The best way is to choose all of Hoses in the first group, sum of their weights is equal to 5 and sum of their beauty is 6.
In the second sample there are two friendship groups: Hoses {1, 2, 3} and Hos {4}. Mehrdad can't invite all the Hoses from the first group because their total weight is 12 > 11, thus the best way is to choose the first Hos from the first group and the only one from the second group. The total weight will be 8, and the total beauty will be 7. | [
{
"input": "3 1 5\n3 2 5\n2 4 2\n1 2",
"output": "6"
},
{
"input": "4 2 11\n2 4 6 6\n6 4 2 1\n1 2\n2 3",
"output": "7"
},
{
"input": "10 5 100\n70 67 8 64 28 82 18 61 82 7\n596434 595982 237932 275698 361351 850374 936914 877996 789231 331012\n1 7\n2 4\n3 6\n5 7\n1 5",
"output": "238... | 842 | 614,400 | 3 | 1,200 | |
710 | King Moves | [
"implementation"
] | null | null | The only king stands on the standard chess board. You are given his position in format "cd", where *c* is the column from 'a' to 'h' and *d* is the row from '1' to '8'. Find the number of moves permitted for the king.
Check the king's moves here [https://en.wikipedia.org/wiki/King_(chess)](https://en.wikipedia.org/wiki/King_(chess)). | The only line contains the king's position in the format "cd", where 'c' is the column from 'a' to 'h' and 'd' is the row from '1' to '8'. | Print the only integer *x* — the number of moves permitted for the king. | [
"e4\n"
] | [
"8\n"
] | none | [
{
"input": "e4",
"output": "8"
},
{
"input": "a1",
"output": "3"
},
{
"input": "h8",
"output": "3"
},
{
"input": "a4",
"output": "5"
},
{
"input": "g7",
"output": "8"
},
{
"input": "e1",
"output": "5"
},
{
"input": "b2",
"output": "8"
... | 109 | 20,172,800 | 3 | 1,202 | |
379 | New Year Candles | [
"implementation"
] | null | null | Vasily the Programmer loves romance, so this year he decided to illuminate his room with candles.
Vasily has *a* candles.When Vasily lights up a new candle, it first burns for an hour and then it goes out. Vasily is smart, so he can make *b* went out candles into a new candle. As a result, this new candle can be used like any other new candle.
Now Vasily wonders: for how many hours can his candles light up the room if he acts optimally well? Help him find this number. | The single line contains two integers, *a* and *b* (1<=≤<=*a*<=≤<=1000; 2<=≤<=*b*<=≤<=1000). | Print a single integer — the number of hours Vasily can light up the room for. | [
"4 2\n",
"6 3\n"
] | [
"7\n",
"8\n"
] | Consider the first sample. For the first four hours Vasily lights up new candles, then he uses four burned out candles to make two new ones and lights them up. When these candles go out (stop burning), Vasily can make another candle. Overall, Vasily can light up the room for 7 hours. | [
{
"input": "4 2",
"output": "7"
},
{
"input": "6 3",
"output": "8"
},
{
"input": "1000 1000",
"output": "1001"
},
{
"input": "123 5",
"output": "153"
},
{
"input": "1000 2",
"output": "1999"
},
{
"input": "1 2",
"output": "1"
},
{
"input": ... | 46 | 0 | 3 | 1,204 | |
292 | Connected Components | [
"data structures",
"dfs and similar",
"dp",
"dsu"
] | null | null | We already know of the large corporation where Polycarpus works as a system administrator. The computer network there consists of *n* computers and *m* cables that connect some pairs of computers. In other words, the computer network can be represented as some non-directed graph with *n* nodes and *m* edges. Let's index the computers with integers from 1 to *n*, let's index the cables with integers from 1 to *m*.
Polycarpus was given an important task — check the reliability of his company's network. For that Polycarpus decided to carry out a series of *k* experiments on the computer network, where the *i*-th experiment goes as follows:
1. Temporarily disconnect the cables with indexes from *l**i* to *r**i*, inclusive (the other cables remain connected). 1. Count the number of connected components in the graph that is defining the computer network at that moment. 1. Re-connect the disconnected cables with indexes from *l**i* to *r**i* (that is, restore the initial network).
Help Polycarpus carry out all experiments and for each print the number of connected components in the graph that defines the computer network through the given experiment. Isolated vertex should be counted as single component. | The first line contains two space-separated integers *n*, *m* (2<=≤<=*n*<=≤<=500; 1<=≤<=*m*<=≤<=104) — the number of computers and the number of cables, correspondingly.
The following *m* lines contain the cables' description. The *i*-th line contains space-separated pair of integers *x**i*, *y**i* (1<=≤<=*x**i*,<=*y**i*<=≤<=*n*; *x**i*<=≠<=*y**i*) — the numbers of the computers that are connected by the *i*-th cable. Note that a pair of computers can be connected by multiple cables.
The next line contains integer *k* (1<=≤<=*k*<=≤<=2·104) — the number of experiments. Next *k* lines contain the experiments' descriptions. The *i*-th line contains space-separated integers *l**i*, *r**i* (1<=≤<=*l**i*<=≤<=*r**i*<=≤<=*m*) — the numbers of the cables that Polycarpus disconnects during the *i*-th experiment. | Print *k* numbers, the *i*-th number represents the number of connected components of the graph that defines the computer network during the *i*-th experiment. | [
"6 5\n1 2\n5 4\n2 3\n3 1\n3 6\n6\n1 3\n2 5\n1 5\n5 5\n2 4\n3 3\n"
] | [
"4\n5\n6\n3\n4\n2\n"
] | none | [
{
"input": "6 5\n1 2\n5 4\n2 3\n3 1\n3 6\n6\n1 3\n2 5\n1 5\n5 5\n2 4\n3 3",
"output": "4\n5\n6\n3\n4\n2"
},
{
"input": "2 1\n2 1\n2\n1 1\n1 1",
"output": "2\n2"
},
{
"input": "3 2\n3 2\n3 1\n4\n1 1\n1 2\n2 2\n2 2",
"output": "2\n3\n2\n2"
},
{
"input": "3 3\n2 3\n3 1\n2 1\n5\n... | 0 | 0 | -1 | 1,208 | |
593 | Anton and Lines | [
"geometry",
"sortings"
] | null | null | The teacher gave Anton a large geometry homework, but he didn't do it (as usual) as he participated in a regular round on Codeforces. In the task he was given a set of *n* lines defined by the equations *y*<==<=*k**i*·*x*<=+<=*b**i*. It was necessary to determine whether there is at least one point of intersection of two of these lines, that lays strictly inside the strip between *x*1<=<<=*x*2. In other words, is it true that there are 1<=≤<=*i*<=<<=*j*<=≤<=*n* and *x*',<=*y*', such that:
- *y*'<==<=*k**i*<=*<=*x*'<=+<=*b**i*, that is, point (*x*',<=*y*') belongs to the line number *i*; - *y*'<==<=*k**j*<=*<=*x*'<=+<=*b**j*, that is, point (*x*',<=*y*') belongs to the line number *j*; - *x*1<=<<=*x*'<=<<=*x*2, that is, point (*x*',<=*y*') lies inside the strip bounded by *x*1<=<<=*x*2.
You can't leave Anton in trouble, can you? Write a program that solves the given task. | The first line of the input contains an integer *n* (2<=≤<=*n*<=≤<=100<=000) — the number of lines in the task given to Anton. The second line contains integers *x*1 and *x*2 (<=-<=1<=000<=000<=≤<=*x*1<=<<=*x*2<=≤<=1<=000<=000) defining the strip inside which you need to find a point of intersection of at least two lines.
The following *n* lines contain integers *k**i*, *b**i* (<=-<=1<=000<=000<=≤<=*k**i*,<=*b**i*<=≤<=1<=000<=000) — the descriptions of the lines. It is guaranteed that all lines are pairwise distinct, that is, for any two *i*<=≠<=*j* it is true that either *k**i*<=≠<=*k**j*, or *b**i*<=≠<=*b**j*. | Print "Yes" (without quotes), if there is at least one intersection of two distinct lines, located strictly inside the strip. Otherwise print "No" (without quotes). | [
"4\n1 2\n1 2\n1 0\n0 1\n0 2\n",
"2\n1 3\n1 0\n-1 3\n",
"2\n1 3\n1 0\n0 2\n",
"2\n1 3\n1 0\n0 3\n"
] | [
"NO",
"YES",
"YES",
"NO"
] | In the first sample there are intersections located on the border of the strip, but there are no intersections located strictly inside it. | [
{
"input": "4\n1 2\n1 2\n1 0\n0 1\n0 2",
"output": "NO"
},
{
"input": "2\n1 3\n1 0\n-1 3",
"output": "YES"
},
{
"input": "2\n1 3\n1 0\n0 2",
"output": "YES"
},
{
"input": "2\n1 3\n1 0\n0 3",
"output": "NO"
},
{
"input": "2\n0 1\n-1000000 1000000\n1000000 -1000000"... | 561 | 9,932,800 | 3 | 1,211 | |
702 | Maximum Increase | [
"dp",
"greedy",
"implementation"
] | null | null | You are given array consisting of *n* integers. Your task is to find the maximum length of an increasing subarray of the given array.
A subarray is the sequence of consecutive elements of the array. Subarray is called increasing if each element of this subarray strictly greater than previous. | The first line contains single positive integer *n* (1<=≤<=*n*<=≤<=105) — the number of integers.
The second line contains *n* positive integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=109). | Print the maximum length of an increasing subarray of the given array. | [
"5\n1 7 2 11 15\n",
"6\n100 100 100 100 100 100\n",
"3\n1 2 3\n"
] | [
"3\n",
"1\n",
"3\n"
] | none | [
{
"input": "5\n1 7 2 11 15",
"output": "3"
},
{
"input": "6\n100 100 100 100 100 100",
"output": "1"
},
{
"input": "3\n1 2 3",
"output": "3"
},
{
"input": "1\n1000000000",
"output": "1"
},
{
"input": "10\n802030518 598196518 640274071 983359971 71550121 96204862 7... | 93 | 7,884,800 | 3 | 1,215 | |
892 | Wrath | [
"greedy",
"implementation",
"two pointers"
] | null | null | Hands that shed innocent blood!
There are *n* guilty people in a line, the *i*-th of them holds a claw with length *L**i*. The bell rings and every person kills some of people in front of him. All people kill others at the same time. Namely, the *i*-th person kills the *j*-th person if and only if *j*<=<<=*i* and *j*<=≥<=*i*<=-<=*L**i*.
You are given lengths of the claws. You need to find the total number of alive people after the bell rings. | The first line contains one integer *n* (1<=≤<=*n*<=≤<=106) — the number of guilty people.
Second line contains *n* space-separated integers *L*1,<=*L*2,<=...,<=*L**n* (0<=≤<=*L**i*<=≤<=109), where *L**i* is the length of the *i*-th person's claw. | Print one integer — the total number of alive people after the bell rings. | [
"4\n0 1 0 10\n",
"2\n0 0\n",
"10\n1 1 3 0 0 0 2 1 0 3\n"
] | [
"1\n",
"2\n",
"3\n"
] | In first sample the last person kills everyone in front of him. | [
{
"input": "4\n0 1 0 10",
"output": "1"
},
{
"input": "2\n0 0",
"output": "2"
},
{
"input": "10\n1 1 3 0 0 0 2 1 0 3",
"output": "3"
},
{
"input": "10\n0 0 2 0 0 3 3 2 2 0",
"output": "2"
},
{
"input": "1\n0",
"output": "1"
},
{
"input": "5\n0 0 0 1 0"... | 93 | 0 | 0 | 1,216 | |
152 | Pocket Book | [
"combinatorics"
] | null | null | One day little Vasya found mom's pocket book. The book had *n* names of her friends and unusually enough, each name was exactly *m* letters long. Let's number the names from 1 to *n* in the order in which they are written.
As mom wasn't home, Vasya decided to play with names: he chose three integers *i*, *j*, *k* (1<=≤<=*i*<=<<=*j*<=≤<=*n*, 1<=≤<=*k*<=≤<=*m*), then he took names number *i* and *j* and swapped their prefixes of length *k*. For example, if we take names "CBDAD" and "AABRD" and swap their prefixes with the length of 3, the result will be names "AABAD" and "CBDRD".
You wonder how many different names Vasya can write instead of name number 1, if Vasya is allowed to perform any number of the described actions. As Vasya performs each action, he chooses numbers *i*, *j*, *k* independently from the previous moves and his choice is based entirely on his will. The sought number can be very large, so you should only find it modulo 1000000007 (109<=+<=7). | The first input line contains two integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=100) — the number of names and the length of each name, correspondingly. Then *n* lines contain names, each name consists of exactly *m* uppercase Latin letters. | Print the single number — the number of different names that could end up in position number 1 in the pocket book after the applying the procedures described above. Print the number modulo 1000000007 (109<=+<=7). | [
"2 3\nAAB\nBAA\n",
"4 5\nABABA\nBCGDG\nAAAAA\nYABSA\n"
] | [
"4\n",
"216\n"
] | In the first sample Vasya can get the following names in the position number 1: "AAB", "AAA", "BAA" and "BAB". | [
{
"input": "2 3\nAAB\nBAA",
"output": "4"
},
{
"input": "4 5\nABABA\nBCGDG\nAAAAA\nYABSA",
"output": "216"
},
{
"input": "1 1\nE",
"output": "1"
},
{
"input": "2 2\nNS\nPD",
"output": "4"
},
{
"input": "3 4\nPJKD\nNFJX\nFGFK",
"output": "81"
},
{
"inpu... | 92 | 0 | 3 | 1,217 | |
0 | none | [
"none"
] | null | null | A substring of some string is called the most frequent, if the number of its occurrences is not less than number of occurrences of any other substring.
You are given a set of strings. A string (not necessarily from this set) is called good if all elements of the set are the most frequent substrings of this string. Restore the non-empty good string with minimum length. If several such strings exist, restore lexicographically minimum string. If there are no good strings, print "NO" (without quotes).
A substring of a string is a contiguous subsequence of letters in the string. For example, "ab", "c", "abc" are substrings of string "abc", while "ac" is not a substring of that string.
The number of occurrences of a substring in a string is the number of starting positions in the string where the substring occurs. These occurrences could overlap.
String *a* is lexicographically smaller than string *b*, if *a* is a prefix of *b*, or *a* has a smaller letter at the first position where *a* and *b* differ. | The first line contains integer *n* (1<=≤<=*n*<=≤<=105) — the number of strings in the set.
Each of the next *n* lines contains a non-empty string consisting of lowercase English letters. It is guaranteed that the strings are distinct.
The total length of the strings doesn't exceed 105. | Print the non-empty good string with minimum length. If several good strings exist, print lexicographically minimum among them. Print "NO" (without quotes) if there are no good strings. | [
"4\nmail\nai\nlru\ncf\n",
"3\nkek\npreceq\ncheburek\n"
] | [
"cfmailru\n",
"NO\n"
] | One can show that in the first sample only two good strings with minimum length exist: "cfmailru" and "mailrucf". The first string is lexicographically minimum. | [
{
"input": "4\nmail\nai\nlru\ncf",
"output": "cfmailru"
},
{
"input": "3\nkek\npreceq\ncheburek",
"output": "NO"
},
{
"input": "1\nz",
"output": "z"
},
{
"input": "2\nab\nba",
"output": "NO"
},
{
"input": "2\nac\nbc",
"output": "NO"
},
{
"input": "2\nc... | 62 | 0 | 0 | 1,219 | |
837 | Text Volume | [
"implementation"
] | null | null | You are given a text of single-space separated words, consisting of small and capital Latin letters.
Volume of the word is number of capital letters in the word. Volume of the text is maximum volume of all words in the text.
Calculate the volume of the given text. | The first line contains one integer number *n* (1<=≤<=*n*<=≤<=200) — length of the text.
The second line contains text of single-space separated words *s*1,<=*s*2,<=...,<=*s**i*, consisting only of small and capital Latin letters. | Print one integer number — volume of text. | [
"7\nNonZERO\n",
"24\nthis is zero answer text\n",
"24\nHarbour Space University\n"
] | [
"5\n",
"0\n",
"1\n"
] | In the first example there is only one word, there are 5 capital letters in it.
In the second example all of the words contain 0 capital letters. | [
{
"input": "7\nNonZERO",
"output": "5"
},
{
"input": "24\nthis is zero answer text",
"output": "0"
},
{
"input": "24\nHarbour Space University",
"output": "1"
},
{
"input": "2\nWM",
"output": "2"
},
{
"input": "200\nLBmJKQLCKUgtTxMoDsEerwvLOXsxASSydOqWyULsRcjMYDWd... | 46 | 0 | 0 | 1,221 | |
222 | Cosmic Tables | [
"data structures",
"implementation"
] | null | null | The Free Meteor Association (FMA) has got a problem: as meteors are moving, the Universal Cosmic Descriptive Humorous Program (UCDHP) needs to add a special module that would analyze this movement.
UCDHP stores some secret information about meteors as an *n*<=×<=*m* table with integers in its cells. The order of meteors in the Universe is changing. That's why the main UCDHP module receives the following queries:
- The query to swap two table rows; - The query to swap two table columns; - The query to obtain a secret number in a particular table cell.
As the main UCDHP module is critical, writing the functional of working with the table has been commissioned to you. | The first line contains three space-separated integers *n*, *m* and *k* (1<=≤<=*n*,<=*m*<=≤<=1000, 1<=≤<=*k*<=≤<=500000) — the number of table columns and rows and the number of queries, correspondingly.
Next *n* lines contain *m* space-separated numbers each — the initial state of the table. Each number *p* in the table is an integer and satisfies the inequality 0<=≤<=*p*<=≤<=106.
Next *k* lines contain queries in the format "*s**i* *x**i* *y**i*", where *s**i* is one of the characters "с", "r" or "g", and *x**i*, *y**i* are two integers.
- If *s**i* = "c", then the current query is the query to swap columns with indexes *x**i* and *y**i* (1<=≤<=*x*,<=*y*<=≤<=*m*,<=*x*<=≠<=*y*); - If *s**i* = "r", then the current query is the query to swap rows with indexes *x**i* and *y**i* (1<=≤<=*x*,<=*y*<=≤<=*n*,<=*x*<=≠<=*y*); - If *s**i* = "g", then the current query is the query to obtain the number that located in the *x**i*-th row and in the *y**i*-th column (1<=≤<=*x*<=≤<=*n*,<=1<=≤<=*y*<=≤<=*m*).
The table rows are considered to be indexed from top to bottom from 1 to *n*, and the table columns — from left to right from 1 to *m*. | For each query to obtain a number (*s**i* = "g") print the required number. Print the answers to the queries in the order of the queries in the input. | [
"3 3 5\n1 2 3\n4 5 6\n7 8 9\ng 3 2\nr 3 2\nc 2 3\ng 2 2\ng 3 2\n",
"2 3 3\n1 2 4\n3 1 5\nc 2 1\nr 1 2\ng 1 3\n"
] | [
"8\n9\n6\n",
"5\n"
] | Let's see how the table changes in the second test case.
After the first operation is fulfilled, the table looks like that:
2 1 4
1 3 5
After the second operation is fulfilled, the table looks like that:
1 3 5
2 1 4
So the answer to the third query (the number located in the first row and in the third column) will be 5. | [
{
"input": "3 3 5\n1 2 3\n4 5 6\n7 8 9\ng 3 2\nr 3 2\nc 2 3\ng 2 2\ng 3 2",
"output": "8\n9\n6"
},
{
"input": "2 3 3\n1 2 4\n3 1 5\nc 2 1\nr 1 2\ng 1 3",
"output": "5"
},
{
"input": "1 1 15\n1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1 1\ng 1... | 0 | 0 | -1 | 1,223 | |
948 | Protect Sheep | [
"brute force",
"dfs and similar",
"graphs",
"implementation"
] | null | null | Bob is a farmer. He has a large pasture with many sheep. Recently, he has lost some of them due to wolf attacks. He thus decided to place some shepherd dogs in such a way that all his sheep are protected.
The pasture is a rectangle consisting of *R*<=×<=*C* cells. Each cell is either empty, contains a sheep, a wolf or a dog. Sheep and dogs always stay in place, but wolves can roam freely around the pasture, by repeatedly moving to the left, right, up or down to a neighboring cell. When a wolf enters a cell with a sheep, it consumes it. However, no wolf can enter a cell with a dog.
Initially there are no dogs. Place dogs onto the pasture in such a way that no wolf can reach any sheep, or determine that it is impossible. Note that since you have many dogs, you do not need to minimize their number. | First line contains two integers *R* (1<=≤<=*R*<=≤<=500) and *C* (1<=≤<=*C*<=≤<=500), denoting the number of rows and the numbers of columns respectively.
Each of the following *R* lines is a string consisting of exactly *C* characters, representing one row of the pasture. Here, 'S' means a sheep, 'W' a wolf and '.' an empty cell. | If it is impossible to protect all sheep, output a single line with the word "No".
Otherwise, output a line with the word "Yes". Then print *R* lines, representing the pasture after placing dogs. Again, 'S' means a sheep, 'W' a wolf, 'D' is a dog and '.' an empty space. You are not allowed to move, remove or add a sheep or a wolf.
If there are multiple solutions, you may print any of them. You don't have to minimize the number of dogs. | [
"6 6\n..S...\n..S.W.\n.S....\n..W...\n...W..\n......\n",
"1 2\nSW\n",
"5 5\n.S...\n...S.\nS....\n...S.\n.S...\n"
] | [
"Yes\n..SD..\n..SDW.\n.SD...\n.DW...\nDD.W..\n......\n",
"No\n",
"Yes\n.S...\n...S.\nS.D..\n...S.\n.S...\n"
] | In the first example, we can split the pasture into two halves, one containing wolves and one containing sheep. Note that the sheep at (2,1) is safe, as wolves cannot move diagonally.
In the second example, there are no empty spots to put dogs that would guard the lone sheep.
In the third example, there are no wolves, so the task is very easy. We put a dog in the center to observe the peacefulness of the meadow, but the solution would be correct even without him. | [
{
"input": "1 2\nSW",
"output": "No"
},
{
"input": "10 10\n....W.W.W.\n.........S\n.S.S...S..\nW.......SS\n.W..W.....\n.W...W....\nS..S...S.S\n....W...S.\n..S..S.S.S\nSS.......S",
"output": "Yes\nDDDDWDWDWD\nDDDDDDDDDS\nDSDSDDDSDD\nWDDDDDDDSS\nDWDDWDDDDD\nDWDDDWDDDD\nSDDSDDDSDS\nDDDDWDDDSD\nDDSD... | 62 | 5,017,600 | 0 | 1,228 | |
909 | Generate Login | [
"brute force",
"greedy",
"sortings"
] | null | null | The preferred way to generate user login in Polygon is to concatenate a prefix of the user's first name and a prefix of their last name, in that order. Each prefix must be non-empty, and any of the prefixes can be the full name. Typically there are multiple possible logins for each person.
You are given the first and the last name of a user. Return the alphabetically earliest login they can get (regardless of other potential Polygon users).
As a reminder, a prefix of a string *s* is its substring which occurs at the beginning of *s*: "a", "ab", "abc" etc. are prefixes of string "{abcdef}" but "b" and 'bc" are not. A string *a* is alphabetically earlier than a string *b*, if *a* is a prefix of *b*, or *a* and *b* coincide up to some position, and then *a* has a letter that is alphabetically earlier than the corresponding letter in *b*: "a" and "ab" are alphabetically earlier than "ac" but "b" and "ba" are alphabetically later than "ac". | The input consists of a single line containing two space-separated strings: the first and the last names. Each character of each string is a lowercase English letter. The length of each string is between 1 and 10, inclusive. | Output a single string — alphabetically earliest possible login formed from these names. The output should be given in lowercase as well. | [
"harry potter\n",
"tom riddle\n"
] | [
"hap\n",
"tomr\n"
] | none | [
{
"input": "harry potter",
"output": "hap"
},
{
"input": "tom riddle",
"output": "tomr"
},
{
"input": "a qdpinbmcrf",
"output": "aq"
},
{
"input": "wixjzniiub ssdfodfgap",
"output": "wis"
},
{
"input": "z z",
"output": "zz"
},
{
"input": "ertuyivhfg v"... | 78 | 5,529,600 | 3 | 1,229 | |
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 the direction $\vec{v_i}$ or $-\vec{v_i}$. In other words, if his position is currently $p = (x, y)$, he will either move to $p + \vec{v_i}$ or $p - \vec{v_i}$.
Allen doesn't want to wander too far from home (which happens to also be the bar). You need to help him figure out a sequence of moves (a sequence of signs for the vectors) such that his final position $p$ satisfies $|p| \le 1.5 \cdot 10^6$ so that he can stay safe. | 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 "
... | 639 | 13,004,800 | 0 | 1,231 | |
16 | Monitor | [
"binary search",
"number theory"
] | C. Monitor | 0 | 64 | Reca company makes monitors, the most popular of their models is AB999 with the screen size *a*<=×<=*b* centimeters. Because of some production peculiarities a screen parameters are integer numbers. Recently the screen sides ratio *x*:<=*y* became popular with users. That's why the company wants to reduce monitor AB999 size so that its screen sides ratio becomes *x*:<=*y*, at the same time they want its total area to be maximal of all possible variants. Your task is to find the screen parameters of the reduced size model, or find out that such a reduction can't be performed. | The first line of the input contains 4 integers — *a*, *b*, *x* and *y* (1<=≤<=*a*,<=*b*,<=*x*,<=*y*<=≤<=2·109). | If the answer exists, output 2 positive integers — screen parameters of the reduced size model. Output 0 0 otherwise. | [
"800 600 4 3\n",
"1920 1200 16 9\n",
"1 1 1 2\n"
] | [
"800 600\n",
"1920 1080\n",
"0 0\n"
] | none | [
{
"input": "800 600 4 3",
"output": "800 600"
},
{
"input": "1920 1200 16 9",
"output": "1920 1080"
},
{
"input": "1 1 1 2",
"output": "0 0"
},
{
"input": "1002105126 227379125 179460772 1295256518",
"output": "0 0"
},
{
"input": "625166755 843062051 1463070160 19... | 500 | 0 | 0 | 1,232 |
507 | Amr and Pins | [
"geometry",
"math"
] | null | null | Amr loves Geometry. One day he came up with a very interesting problem.
Amr has a circle of radius *r* and center in point (*x*,<=*y*). He wants the circle center to be in new position (*x*',<=*y*').
In one step Amr can put a pin to the border of the circle in a certain point, then rotate the circle around that pin by any angle and finally remove the pin.
Help Amr to achieve his goal in minimum number of steps. | Input consists of 5 space-separated integers *r*, *x*, *y*, *x*' *y*' (1<=≤<=*r*<=≤<=105, <=-<=105<=≤<=*x*,<=*y*,<=*x*',<=*y*'<=≤<=105), circle radius, coordinates of original center of the circle and coordinates of destination center of the circle respectively. | Output a single integer — minimum number of steps required to move the center of the circle to the destination point. | [
"2 0 0 0 4\n",
"1 1 1 4 4\n",
"4 5 6 5 6\n"
] | [
"1\n",
"3\n",
"0\n"
] | In the first sample test the optimal way is to put a pin at point (0, 2) and rotate the circle by 180 degrees counter-clockwise (or clockwise, no matter).
<img class="tex-graphics" src="https://espresso.codeforces.com/4e40fd4cc24a2050a0488aa131e6244369328039.png" style="max-width: 100.0%;max-height: 100.0%;"/> | [
{
"input": "2 0 0 0 4",
"output": "1"
},
{
"input": "1 1 1 4 4",
"output": "3"
},
{
"input": "4 5 6 5 6",
"output": "0"
},
{
"input": "10 20 0 40 0",
"output": "1"
},
{
"input": "9 20 0 40 0",
"output": "2"
},
{
"input": "5 -1 -6 -5 1",
"output": "... | 93 | 0 | 3 | 1,235 | |
112 | Petya and Strings | [
"implementation",
"strings"
] | A. Petya and Strings | 2 | 256 | Little Petya loves presents. His mum bought him two strings of the same size for his birthday. The strings consist of uppercase and lowercase Latin letters. Now Petya wants to compare those two strings lexicographically. The letters' case does not matter, that is an uppercase letter is considered equivalent to the corresponding lowercase letter. Help Petya perform the comparison. | Each of the first two lines contains a bought string. The strings' lengths range from 1 to 100 inclusive. It is guaranteed that the strings are of the same length and also consist of uppercase and lowercase Latin letters. | If the first string is less than the second one, print "-1". If the second string is less than the first one, print "1". If the strings are equal, print "0". Note that the letters' case is not taken into consideration when the strings are compared. | [
"aaaa\naaaA\n",
"abs\nAbz\n",
"abcdefg\nAbCdEfF\n"
] | [
"0\n",
"-1\n",
"1\n"
] | If you want more formal information about the lexicographical order (also known as the "dictionary order" or "alphabetical order"), you can visit the following site:
- http://en.wikipedia.org/wiki/Lexicographical_order | [
{
"input": "aaaa\naaaA",
"output": "0"
},
{
"input": "abs\nAbz",
"output": "-1"
},
{
"input": "abcdefg\nAbCdEfF",
"output": "1"
},
{
"input": "asadasdasd\nasdwasdawd",
"output": "-1"
},
{
"input": "aslkjlkasdd\nasdlkjdajwi",
"output": "1"
},
{
"input":... | 92 | 0 | 3.977 | 1,236 |
329 | Purification | [
"constructive algorithms",
"greedy"
] | null | null | You are an adventurer currently journeying inside an evil temple. After defeating a couple of weak zombies, you arrived at a square room consisting of tiles forming an *n*<=×<=*n* grid. The rows are numbered 1 through *n* from top to bottom, and the columns are numbered 1 through *n* from left to right. At the far side of the room lies a door locked with evil magical forces. The following inscriptions are written on the door:
Being a very senior adventurer, you immediately realize what this means. You notice that every single cell in the grid are initially evil. You should purify all of these cells.
The only method of tile purification known to you is by casting the "Purification" spell. You cast this spell on a single tile — then, all cells that are located in the same row and all cells that are located in the same column as the selected tile become purified (including the selected tile)! It is allowed to purify a cell more than once.
You would like to purify all *n*<=×<=*n* cells while minimizing the number of times you cast the "Purification" spell. This sounds very easy, but you just noticed that some tiles are particularly more evil than the other tiles. You cannot cast the "Purification" spell on those particularly more evil tiles, not even after they have been purified. They can still be purified if a cell sharing the same row or the same column gets selected by the "Purification" spell.
Please find some way to purify all the cells with the minimum number of spells cast. Print -1 if there is no such way. | The first line will contain a single integer *n* (1<=≤<=*n*<=≤<=100). Then, *n* lines follows, each contains *n* characters. The *j*-th character in the *i*-th row represents the cell located at row *i* and column *j*. It will be the character 'E' if it is a particularly more evil cell, and '.' otherwise. | If there exists no way to purify all the cells, output -1. Otherwise, if your solution casts *x* "Purification" spells (where *x* is the minimum possible number of spells), output *x* lines. Each line should consist of two integers denoting the row and column numbers of the cell on which you should cast the "Purification" spell. | [
"3\n.E.\nE.E\n.E.\n",
"3\nEEE\nE..\nE.E\n",
"5\nEE.EE\nE.EE.\nE...E\n.EE.E\nEE.EE\n"
] | [
"1 1\n2 2\n3 3\n",
"-1\n",
"3 3\n1 3\n2 2\n4 4\n5 3"
] | The first example is illustrated as follows. Purple tiles are evil tiles that have not yet been purified. Red tile is the tile on which "Purification" is cast. Yellow tiles are the tiles being purified as a result of the current "Purification" spell. Green tiles are tiles that have been purified previously.
In the second example, it is impossible to purify the cell located at row 1 and column 1.
For the third example: | [
{
"input": "3\n.E.\nE.E\n.E.",
"output": "1 1\n2 2\n3 1"
},
{
"input": "3\nEEE\nE..\nE.E",
"output": "-1"
},
{
"input": "5\nEE.EE\nE.EE.\nE...E\n.EE.E\nEE.EE",
"output": "1 3\n2 2\n3 2\n4 1\n5 3"
},
{
"input": "3\n.EE\n.EE\n.EE",
"output": "1 1\n2 1\n3 1"
},
{
"in... | 0 | 0 | -1 | 1,242 | |
182 | Battlefield | [
"geometry",
"graphs",
"implementation",
"shortest paths"
] | null | null | Vasya lagged behind at the University and got to the battlefield. Just joking! He's simply playing some computer game. The field is a flat platform with *n* trenches dug on it. The trenches are segments on a plane parallel to the coordinate axes. No two trenches intersect.
There is a huge enemy laser far away from Vasya. The laser charges for *a* seconds, and then shoots continuously for *b* seconds. Then, it charges for *a* seconds again. Then it shoots continuously for *b* seconds again and so on. Vasya knows numbers *a* and *b*. He also knows that while the laser is shooting, Vasya must be in the trench, but while the laser is charging, Vasya can safely move around the field. The main thing is to have time to hide in the trench before the shot. If Vasya reaches the trench exactly at the moment when the laser starts shooting, we believe that Vasya managed to hide. Coincidentally, the length of any trench in meters numerically does not exceed *b*.
Initially, Vasya is at point *A*. He needs to get to point *B*. Vasya moves at speed 1 meter per second in either direction. You can get in or out of the trench at any its point. Getting in or out of the trench takes no time. It is also possible to move in the trench, without leaving it.
What is the minimum time Vasya needs to get from point *A* to point *B*, if at the initial time the laser has just started charging? If Vasya cannot get from point *A* to point *B*, print -1. If Vasya reaches point *B* at the moment when the laser begins to shoot, it is believed that Vasya managed to reach point *B*. | The first line contains two space-separated integers: *a* and *b* (1<=≤<=*a*,<=*b*<=≤<=1000), — the duration of charging and the duration of shooting, in seconds.
The second line contains four space-separated integers: *A**x*, *A**y*, *B**x*, *B**y* (<=-<=104<=≤<=*A**x*,<=*A**y*,<=*B**x*,<=*B**y*<=≤<=104) — the coordinates of points *А* and *B*. It is guaranteed that points *A* and *B* do not belong to any trench.
The third line contains a single integer: *n* (1<=≤<=*n*<=≤<=1000), — the number of trenches.
Each of the following *n* lines contains four space-separated integers: *x*1, *y*1, *x*2, *y*2 (<=-<=104<=≤<=*x**i*,<=*y**i*<=≤<=104) — the coordinates of ends of the corresponding trench.
All coordinates are given in meters. It is guaranteed that for any trench either *x*1<==<=*x*2, or *y*1<==<=*y*2. No two trenches intersect. The length of any trench in meters doesn't exceed *b* numerically. | If Vasya can get from point *A* to point *B*, print the minimum time he will need for it. Otherwise, print number -1.
The answer will be considered correct if the absolute or relative error does not exceed 10<=-<=4 | [
"2 4\n0 5 6 5\n3\n0 0 0 4\n1 1 4 1\n6 0 6 4\n",
"5 10\n0 0 10 10\n1\n5 0 5 9\n"
] | [
"19.0000000000\n",
"-1\n"
] | none | [] | 60 | 0 | 0 | 1,243 | |
519 | A and B and Team Training | [
"greedy",
"implementation",
"math",
"number theory"
] | null | null | A and B are preparing themselves for programming contests.
An important part of preparing for a competition is sharing programming knowledge from the experienced members to those who are just beginning to deal with the contests. Therefore, during the next team training A decided to make teams so that newbies are solving problems together with experienced participants.
A believes that the optimal team of three people should consist of one experienced participant and two newbies. Thus, each experienced participant can share the experience with a large number of people.
However, B believes that the optimal team should have two experienced members plus one newbie. Thus, each newbie can gain more knowledge and experience.
As a result, A and B have decided that all the teams during the training session should belong to one of the two types described above. Furthermore, they agree that the total number of teams should be as much as possible.
There are *n* experienced members and *m* newbies on the training session. Can you calculate what maximum number of teams can be formed? | The first line contains two integers *n* and *m* (0<=≤<=*n*,<=*m*<=≤<=5·105) — the number of experienced participants and newbies that are present at the training session. | Print the maximum number of teams that can be formed. | [
"2 6\n",
"4 5\n"
] | [
"2\n",
"3\n"
] | Let's represent the experienced players as XP and newbies as NB.
In the first test the teams look as follows: (XP, NB, NB), (XP, NB, NB).
In the second test sample the teams look as follows: (XP, NB, NB), (XP, NB, NB), (XP, XP, NB). | [
{
"input": "2 6",
"output": "2"
},
{
"input": "4 5",
"output": "3"
},
{
"input": "1 1",
"output": "0"
},
{
"input": "3 3",
"output": "2"
},
{
"input": "500000 500000",
"output": "333333"
},
{
"input": "70 100",
"output": "56"
},
{
"input": ... | 0 | 0 | -1 | 1,245 | |
791 | Bear and Big Brother | [
"implementation"
] | null | null | Bear Limak wants to become the largest of bears, or at least to become larger than his brother Bob.
Right now, Limak and Bob weigh *a* and *b* respectively. It's guaranteed that Limak's weight is smaller than or equal to his brother's weight.
Limak eats a lot and his weight is tripled after every year, while Bob's weight is doubled after every year.
After how many full years will Limak become strictly larger (strictly heavier) than Bob? | The only line of the input contains two integers *a* and *b* (1<=≤<=*a*<=≤<=*b*<=≤<=10) — the weight of Limak and the weight of Bob respectively. | Print one integer, denoting the integer number of years after which Limak will become strictly larger than Bob. | [
"4 7\n",
"4 9\n",
"1 1\n"
] | [
"2\n",
"3\n",
"1\n"
] | In the first sample, Limak weighs 4 and Bob weighs 7 initially. After one year their weights are 4·3 = 12 and 7·2 = 14 respectively (one weight is tripled while the other one is doubled). Limak isn't larger than Bob yet. After the second year weights are 36 and 28, so the first weight is greater than the second one. Limak became larger than Bob after two years so you should print 2.
In the second sample, Limak's and Bob's weights in next years are: 12 and 18, then 36 and 36, and finally 108 and 72 (after three years). The answer is 3. Remember that Limak wants to be larger than Bob and he won't be satisfied with equal weights.
In the third sample, Limak becomes larger than Bob after the first year. Their weights will be 3 and 2 then. | [
{
"input": "4 7",
"output": "2"
},
{
"input": "4 9",
"output": "3"
},
{
"input": "1 1",
"output": "1"
},
{
"input": "4 6",
"output": "2"
},
{
"input": "1 10",
"output": "6"
},
{
"input": "1 1",
"output": "1"
},
{
"input": "1 2",
"output... | 249 | 268,390,400 | 0 | 1,246 | |
961 | Tetris | [
"implementation"
] | null | null | You are given a following process.
There is a platform with $n$ columns. $1 \times 1$ squares are appearing one after another in some columns on this platform. If there are no squares in the column, a square will occupy the bottom row. Otherwise a square will appear at the top of the highest square of this column.
When all of the $n$ columns have at least one square in them, the bottom row is being removed. You will receive $1$ point for this, and all the squares left will fall down one row.
You task is to calculate the amount of points you will receive. | The first line of input contain 2 integer numbers $n$ and $m$ ($1 \le n, m \le 1000$) — the length of the platform and the number of the squares.
The next line contain $m$ integer numbers $c_1, c_2, \dots, c_m$ ($1 \le c_i \le n$) — column in which $i$-th square will appear. | Print one integer — the amount of points you will receive. | [
"3 9\n1 1 2 2 2 3 1 2 3\n"
] | [
"2\n"
] | In the sample case the answer will be equal to $2$ because after the appearing of $6$-th square will be removed one row (counts of the squares on the platform will look like $[2~ 3~ 1]$, and after removing one row will be $[1~ 2~ 0]$).
After the appearing of $9$-th square counts will be $[2~ 3~ 1]$, and after removing one row it will look like $[1~ 2~ 0]$.
So the answer will be equal to $2$. | [
{
"input": "3 9\n1 1 2 2 2 3 1 2 3",
"output": "2"
},
{
"input": "1 7\n1 1 1 1 1 1 1",
"output": "7"
},
{
"input": "1 1\n1",
"output": "1"
},
{
"input": "3 5\n1 1 1 2 3",
"output": "1"
},
{
"input": "4 6\n4 4 4 4 4 4",
"output": "0"
},
{
"input": "4 6\... | 93 | 0 | -1 | 1,250 | |
620 | Professor GukiZ's Robot | [
"implementation",
"math"
] | null | null | Professor GukiZ makes a new robot. The robot are in the point with coordinates (*x*1,<=*y*1) and should go to the point (*x*2,<=*y*2). In a single step the robot can change any of its coordinates (maybe both of them) by one (decrease or increase). So the robot can move in one of the 8 directions. Find the minimal number of steps the robot should make to get the finish position. | The first line contains two integers *x*1,<=*y*1 (<=-<=109<=≤<=*x*1,<=*y*1<=≤<=109) — the start position of the robot.
The second line contains two integers *x*2,<=*y*2 (<=-<=109<=≤<=*x*2,<=*y*2<=≤<=109) — the finish position of the robot. | Print the only integer *d* — the minimal number of steps to get the finish position. | [
"0 0\n4 5\n",
"3 4\n6 1\n"
] | [
"5\n",
"3\n"
] | In the first example robot should increase both of its coordinates by one four times, so it will be in position (4, 4). After that robot should simply increase its *y* coordinate and get the finish position.
In the second example robot should simultaneously increase *x* coordinate and decrease *y* coordinate by one three times. | [
{
"input": "0 0\n4 5",
"output": "5"
},
{
"input": "3 4\n6 1",
"output": "3"
},
{
"input": "0 0\n4 6",
"output": "6"
},
{
"input": "1 1\n-3 -5",
"output": "6"
},
{
"input": "-1 -1\n-10 100",
"output": "101"
},
{
"input": "1 -1\n100 -100",
"output":... | 62 | 0 | 3 | 1,251 | |
856 | Similar Words | [
"dp",
"hashing",
"strings",
"trees"
] | null | null | Let us call a non-empty sequence of lowercase English letters a word. Prefix of a word *x* is a word *y* that can be obtained from *x* by removing zero or more last letters of *x*.
Let us call two words similar, if one of them can be obtained from the other by removing its first letter.
You are given a set *S* of words. Find the maximal possible size of set of non-empty words *X* such that they satisfy the following:
- each word of *X* is prefix of some word from *S*; - *X* has no similar words. | Input data contains multiple test cases. The first line of the input data contains an integer *t* — the number of test cases. The descriptions of test cases follow.
The first line of each description contains an integer *n* — the number of words in the set *S* (1<=≤<=*n*<=≤<=106). Each of the following *n* lines contains one non-empty word — elements of *S*. All words in *S* are different.
It is guaranteed that the total length of all words in one input data doesn't exceed 106. | For each test case print one line that contains one integer *m* — the maximal number of words that *X* can contain. | [
"2\n3\naba\nbaba\naaab\n2\naa\na\n"
] | [
"6\n1\n"
] | none | [] | 30 | 0 | 0 | 1,252 | |
436 | Om Nom and Spiders | [
"implementation",
"math"
] | null | null | Om Nom really likes candies and doesn't like spiders as they frequently steal candies. One day Om Nom fancied a walk in a park. Unfortunately, the park has some spiders and Om Nom doesn't want to see them at all.
The park can be represented as a rectangular *n*<=×<=*m* field. The park has *k* spiders, each spider at time 0 is at some cell of the field. The spiders move all the time, and each spider always moves in one of the four directions (left, right, down, up). In a unit of time, a spider crawls from his cell to the side-adjacent cell in the corresponding direction. If there is no cell in the given direction, then the spider leaves the park. The spiders do not interfere with each other as they move. Specifically, one cell can have multiple spiders at the same time.
Om Nom isn't yet sure where to start his walk from but he definitely wants:
- to start walking at time 0 at an upper row cell of the field (it is guaranteed that the cells in this row do not contain any spiders); - to walk by moving down the field towards the lowest row (the walk ends when Om Nom leaves the boundaries of the park).
We know that Om Nom moves by jumping. One jump takes one time unit and transports the little monster from his cell to either a side-adjacent cell on the lower row or outside the park boundaries.
Each time Om Nom lands in a cell he sees all the spiders that have come to that cell at this moment of time. Om Nom wants to choose the optimal cell to start the walk from. That's why he wonders: for each possible starting cell, how many spiders will he see during the walk if he starts from this cell? Help him and calculate the required value for each possible starting cell. | The first line contains three integers *n*,<=*m*,<=*k* (2<=≤<=*n*,<=*m*<=≤<=2000; 0<=≤<=*k*<=≤<=*m*(*n*<=-<=1)).
Each of the next *n* lines contains *m* characters — the description of the park. The characters in the *i*-th line describe the *i*-th row of the park field. If the character in the line equals ".", that means that the corresponding cell of the field is empty; otherwise, the character in the line will equal one of the four characters: "L" (meaning that this cell has a spider at time 0, moving left), "R" (a spider moving right), "U" (a spider moving up), "D" (a spider moving down).
It is guaranteed that the first row doesn't contain any spiders. It is guaranteed that the description of the field contains no extra characters. It is guaranteed that at time 0 the field contains exactly *k* spiders. | Print *m* integers: the *j*-th integer must show the number of spiders Om Nom will see if he starts his walk from the *j*-th cell of the first row. The cells in any row of the field are numbered from left to right. | [
"3 3 4\n...\nR.L\nR.U\n",
"2 2 2\n..\nRL\n",
"2 2 2\n..\nLR\n",
"3 4 8\n....\nRRLL\nUUUU\n",
"2 2 2\n..\nUU\n"
] | [
"0 2 2 ",
"1 1 ",
"0 0 ",
"1 3 3 1 ",
"0 0 "
] | Consider the first sample. The notes below show how the spider arrangement changes on the field over time:
Character "*" represents a cell that contains two spiders at the same time.
- If Om Nom starts from the first cell of the first row, he won't see any spiders. - If he starts from the second cell, he will see two spiders at time 1. - If he starts from the third cell, he will see two spiders: one at time 1, the other one at time 2. | [
{
"input": "3 3 4\n...\nR.L\nR.U",
"output": "0 2 2 "
},
{
"input": "2 2 2\n..\nRL",
"output": "1 1 "
},
{
"input": "2 2 2\n..\nLR",
"output": "0 0 "
},
{
"input": "3 4 8\n....\nRRLL\nUUUU",
"output": "1 3 3 1 "
},
{
"input": "2 2 2\n..\nUU",
"output": "0 0 "
... | 170 | 8,704,000 | 3 | 1,254 | |
33 | What is for dinner? | [
"greedy",
"implementation"
] | A. What is for dinner? | 2 | 256 | In one little known, but very beautiful country called Waterland, lives a lovely shark Valerie. Like all the sharks, she has several rows of teeth, and feeds on crucians. One of Valerie's distinguishing features is that while eating one crucian she uses only one row of her teeth, the rest of the teeth are "relaxing".
For a long time our heroine had been searching the sea for crucians, but a great misfortune happened. Her teeth started to ache, and she had to see the local dentist, lobster Ashot. As a professional, Ashot quickly relieved Valerie from her toothache. Moreover, he managed to determine the cause of Valerie's developing caries (for what he was later nicknamed Cap).
It turned that Valerie eats too many crucians. To help Valerie avoid further reoccurrence of toothache, Ashot found for each Valerie's tooth its residual viability. Residual viability of a tooth is a value equal to the amount of crucians that Valerie can eat with this tooth. Every time Valerie eats a crucian, viability of all the teeth used for it will decrease by one. When the viability of at least one tooth becomes negative, the shark will have to see the dentist again.
Unhappy, Valerie came back home, where a portion of crucians was waiting for her. For sure, the shark couldn't say no to her favourite meal, but she had no desire to go back to the dentist. That's why she decided to eat the maximum amount of crucians from the portion but so that the viability of no tooth becomes negative.
As Valerie is not good at mathematics, she asked you to help her to find out the total amount of crucians that she can consume for dinner.
We should remind you that while eating one crucian Valerie uses exactly one row of teeth and the viability of each tooth from this row decreases by one. | The first line contains three integers *n*, *m*, *k* (1<=≤<=*m*<=≤<=*n*<=≤<=1000,<=0<=≤<=*k*<=≤<=106) — total amount of Valerie's teeth, amount of tooth rows and amount of crucians in Valerie's portion for dinner. Then follow *n* lines, each containing two integers: *r* (1<=≤<=*r*<=≤<=*m*) — index of the row, where belongs the corresponding tooth, and *c* (0<=≤<=*c*<=≤<=106) — its residual viability.
It's guaranteed that each tooth row has positive amount of teeth. | In the first line output the maximum amount of crucians that Valerie can consume for dinner. | [
"4 3 18\n2 3\n1 2\n3 6\n2 3\n",
"2 2 13\n1 13\n2 12\n"
] | [
"11\n",
"13\n"
] | none | [
{
"input": "4 3 18\n2 3\n1 2\n3 6\n2 3",
"output": "11"
},
{
"input": "2 2 13\n1 13\n2 12",
"output": "13"
},
{
"input": "5 4 8\n4 6\n4 5\n1 3\n2 0\n3 3",
"output": "8"
},
{
"input": "1 1 0\n1 3",
"output": "0"
},
{
"input": "7 1 30\n1 8\n1 15\n1 5\n1 17\n1 9\n1 1... | 92 | 512,000 | -1 | 1,255 |
26 | Almost Prime | [
"number theory"
] | A. Almost Prime | 2 | 256 | A number is called almost prime if it has exactly two distinct prime divisors. For example, numbers 6, 18, 24 are almost prime, while 4, 8, 9, 42 are not. Find the amount of almost prime numbers which are between 1 and *n*, inclusive. | Input contains one integer number *n* (1<=≤<=*n*<=≤<=3000). | Output the amount of almost prime numbers between 1 and *n*, inclusive. | [
"10\n",
"21\n"
] | [
"2\n",
"8\n"
] | none | [
{
"input": "10",
"output": "2"
},
{
"input": "21",
"output": "8"
},
{
"input": "1",
"output": "0"
},
{
"input": "2",
"output": "0"
},
{
"input": "4",
"output": "0"
},
{
"input": "3",
"output": "0"
},
{
"input": "8",
"output": "1"
},
... | 186 | 3,174,400 | 3.947587 | 1,257 |
492 | Vanya and Exams | [
"greedy",
"sortings"
] | null | null | Vanya wants to pass *n* exams and get the academic scholarship. He will get the scholarship if the average grade mark for all the exams is at least *avg*. The exam grade cannot exceed *r*. Vanya has passed the exams and got grade *a**i* for the *i*-th exam. To increase the grade for the *i*-th exam by 1 point, Vanya must write *b**i* essays. He can raise the exam grade multiple times.
What is the minimum number of essays that Vanya needs to write to get scholarship? | The first line contains three integers *n*, *r*, *avg* (1<=≤<=*n*<=≤<=105, 1<=≤<=*r*<=≤<=109, 1<=≤<=*avg*<=≤<=*min*(*r*,<=106)) — the number of exams, the maximum grade and the required grade point average, respectively.
Each of the following *n* lines contains space-separated integers *a**i* and *b**i* (1<=≤<=*a**i*<=≤<=*r*, 1<=≤<=*b**i*<=≤<=106). | In the first line print the minimum number of essays. | [
"5 5 4\n5 2\n4 7\n3 1\n3 2\n2 5\n",
"2 5 4\n5 2\n5 2\n"
] | [
"4\n",
"0\n"
] | In the first sample Vanya can write 2 essays for the 3rd exam to raise his grade by 2 points and 2 essays for the 4th exam to raise his grade by 1 point.
In the second sample, Vanya doesn't need to write any essays as his general point average already is above average. | [
{
"input": "5 5 4\n5 2\n4 7\n3 1\n3 2\n2 5",
"output": "4"
},
{
"input": "2 5 4\n5 2\n5 2",
"output": "0"
},
{
"input": "6 5 5\n1 7\n2 4\n3 5\n4 6\n5 6\n4 7",
"output": "63"
},
{
"input": "1 1000000000 1000000\n1 1000000",
"output": "999999000000"
},
{
"input": "1... | 702 | 14,643,200 | 3 | 1,259 | |
770 | New Password | [
"*special",
"implementation"
] | null | null | Innokentiy decides to change the password in the social net "Contact!", but he is too lazy to invent a new password by himself. That is why he needs your help.
Innokentiy decides that new password should satisfy the following conditions:
- the length of the password must be equal to *n*, - the password should consist only of lowercase Latin letters, - the number of distinct symbols in the password must be equal to *k*, - any two consecutive symbols in the password must be distinct.
Your task is to help Innokentiy and to invent a new password which will satisfy all given conditions. | The first line contains two positive integers *n* and *k* (2<=≤<=*n*<=≤<=100, 2<=≤<=*k*<=≤<=*min*(*n*,<=26)) — the length of the password and the number of distinct symbols in it.
Pay attention that a desired new password always exists. | Print any password which satisfies all conditions given by Innokentiy. | [
"4 3\n",
"6 6\n",
"5 2\n"
] | [
"java\n",
"python\n",
"phphp\n"
] | In the first test there is one of the appropriate new passwords — java, because its length is equal to 4 and 3 distinct lowercase letters a, j and v are used in it.
In the second test there is one of the appropriate new passwords — python, because its length is equal to 6 and it consists of 6 distinct lowercase letters.
In the third test there is one of the appropriate new passwords — phphp, because its length is equal to 5 and 2 distinct lowercase letters p and h are used in it.
Pay attention the condition that no two identical symbols are consecutive is correct for all appropriate passwords in tests. | [
{
"input": "4 3",
"output": "abca"
},
{
"input": "6 6",
"output": "abcdef"
},
{
"input": "5 2",
"output": "ababa"
},
{
"input": "3 2",
"output": "aba"
},
{
"input": "10 2",
"output": "ababababab"
},
{
"input": "26 13",
"output": "abcdefghijklmabcde... | 77 | 6,656,000 | 0 | 1,261 | |
673 | Bear and Game | [
"implementation"
] | null | null | Bear Limak likes watching sports on TV. He is going to watch a game today. The game lasts 90 minutes and there are no breaks.
Each minute can be either interesting or boring. If 15 consecutive minutes are boring then Limak immediately turns TV off.
You know that there will be *n* interesting minutes *t*1,<=*t*2,<=...,<=*t**n*. Your task is to calculate for how many minutes Limak will watch the game. | The first line of the input contains one integer *n* (1<=≤<=*n*<=≤<=90) — the number of interesting minutes.
The second line contains *n* integers *t*1,<=*t*2,<=...,<=*t**n* (1<=≤<=*t*1<=<<=*t*2<=<<=... *t**n*<=≤<=90), given in the increasing order. | Print the number of minutes Limak will watch the game. | [
"3\n7 20 88\n",
"9\n16 20 30 40 50 60 70 80 90\n",
"9\n15 20 30 40 50 60 70 80 90\n"
] | [
"35\n",
"15\n",
"90\n"
] | In the first sample, minutes 21, 22, ..., 35 are all boring and thus Limak will turn TV off immediately after the 35-th minute. So, he would watch the game for 35 minutes.
In the second sample, the first 15 minutes are boring.
In the third sample, there are no consecutive 15 boring minutes. So, Limak will watch the whole game. | [
{
"input": "3\n7 20 88",
"output": "35"
},
{
"input": "9\n16 20 30 40 50 60 70 80 90",
"output": "15"
},
{
"input": "9\n15 20 30 40 50 60 70 80 90",
"output": "90"
},
{
"input": "30\n6 11 12 15 22 24 30 31 32 33 34 35 40 42 44 45 47 50 53 54 57 58 63 67 75 77 79 81 83 88",
... | 62 | 4,608,000 | 3 | 1,263 | |
0 | none | [
"none"
] | null | null | Santa Claus decided to disassemble his keyboard to clean it. After he returned all the keys back, he suddenly realized that some pairs of keys took each other's place! That is, Santa suspects that each key is either on its place, or on the place of another key, which is located exactly where the first key should be.
In order to make sure that he's right and restore the correct order of keys, Santa typed his favorite patter looking only to his keyboard.
You are given the Santa's favorite patter and the string he actually typed. Determine which pairs of keys could be mixed. Each key must occur in pairs at most once. | The input consists of only two strings *s* and *t* denoting the favorite Santa's patter and the resulting string. *s* and *t* are not empty and have the same length, which is at most 1000. Both strings consist only of lowercase English letters. | If Santa is wrong, and there is no way to divide some of keys into pairs and swap keys in each pair so that the keyboard will be fixed, print «-1» (without quotes).
Otherwise, the first line of output should contain the only integer *k* (*k*<=≥<=0) — the number of pairs of keys that should be swapped. The following *k* lines should contain two space-separated letters each, denoting the keys which should be swapped. All printed letters must be distinct.
If there are several possible answers, print any of them. You are free to choose the order of the pairs and the order of keys in a pair.
Each letter must occur at most once. Santa considers the keyboard to be fixed if he can print his favorite patter without mistakes. | [
"helloworld\nehoolwlroz\n",
"hastalavistababy\nhastalavistababy\n",
"merrychristmas\nchristmasmerry\n"
] | [
"3\nh e\nl o\nd z\n",
"0\n",
"-1\n"
] | none | [
{
"input": "helloworld\nehoolwlroz",
"output": "3\nh e\nl o\nd z"
},
{
"input": "hastalavistababy\nhastalavistababy",
"output": "0"
},
{
"input": "merrychristmas\nchristmasmerry",
"output": "-1"
},
{
"input": "kusyvdgccw\nkusyvdgccw",
"output": "0"
},
{
"input": "... | 124 | 0 | 3 | 1,265 | |
325 | Square and Rectangles | [
"implementation"
] | null | null | You are given *n* rectangles. The corners of rectangles have integer coordinates and their edges are parallel to the *Ox* and *Oy* axes. The rectangles may touch each other, but they do not overlap (that is, there are no points that belong to the interior of more than one rectangle).
Your task is to determine if the rectangles form a square. In other words, determine if the set of points inside or on the border of at least one rectangle is precisely equal to the set of points inside or on the border of some square. | The first line contains a single integer *n* (1<=≤<=*n*<=≤<=5). Next *n* lines contain four integers each, describing a single rectangle: *x*1, *y*1, *x*2, *y*2 (0<=≤<=*x*1<=<<=*x*2<=≤<=31400,<=0<=≤<=*y*1<=<<=*y*2<=≤<=31400) — *x*1 and *x*2 are *x*-coordinates of the left and right edges of the rectangle, and *y*1 and *y*2 are *y*-coordinates of the bottom and top edges of the rectangle.
No two rectangles overlap (that is, there are no points that belong to the interior of more than one rectangle). | In a single line print "YES", if the given rectangles form a square, or "NO" otherwise. | [
"5\n0 0 2 3\n0 3 3 5\n2 0 5 2\n3 2 5 5\n2 2 3 3\n",
"4\n0 0 2 3\n0 3 3 5\n2 0 5 2\n3 2 5 5\n"
] | [
"YES\n",
"NO\n"
] | none | [
{
"input": "5\n0 0 2 3\n0 3 3 5\n2 0 5 2\n3 2 5 5\n2 2 3 3",
"output": "YES"
},
{
"input": "4\n0 0 2 3\n0 3 3 5\n2 0 5 2\n3 2 5 5",
"output": "NO"
},
{
"input": "5\n0 0 10000 20000\n10000 0 15000 19999\n10000 19999 14999 20000\n0 20000 15000 31400\n15000 0 31400 31400",
"output": "NO... | 62 | 307,200 | -1 | 1,267 | |
0 | none | [
"none"
] | null | null | You are given two squares, one with sides parallel to the coordinate axes, and another one with sides at 45 degrees to the coordinate axes. Find whether the two squares intersect.
The interior of the square is considered to be part of the square, i.e. if one square is completely inside another, they intersect. If the two squares only share one common point, they are also considered to intersect. | The input data consists of two lines, one for each square, both containing 4 pairs of integers. Each pair represents coordinates of one vertex of the square. Coordinates within each line are either in clockwise or counterclockwise order.
The first line contains the coordinates of the square with sides parallel to the coordinate axes, the second line contains the coordinates of the square at 45 degrees.
All the values are integer and between $-100$ and $100$. | Print "Yes" if squares intersect, otherwise print "No".
You can print each letter in any case (upper or lower). | [
"0 0 6 0 6 6 0 6\n1 3 3 5 5 3 3 1\n",
"0 0 6 0 6 6 0 6\n7 3 9 5 11 3 9 1\n",
"6 0 6 6 0 6 0 0\n7 4 4 7 7 10 10 7\n"
] | [
"YES\n",
"NO\n",
"YES\n"
] | In the first example the second square lies entirely within the first square, so they do intersect.
In the second sample squares do not have any points in common.
Here are images corresponding to the samples: | [
{
"input": "0 0 6 0 6 6 0 6\n1 3 3 5 5 3 3 1",
"output": "YES"
},
{
"input": "0 0 6 0 6 6 0 6\n7 3 9 5 11 3 9 1",
"output": "NO"
},
{
"input": "6 0 6 6 0 6 0 0\n7 4 4 7 7 10 10 7",
"output": "YES"
},
{
"input": "0 0 6 0 6 6 0 6\n8 4 4 8 8 12 12 8",
"output": "YES"
},
... | 108 | 0 | 0 | 1,268 | |
116 | Tram | [
"implementation"
] | null | null | Linear Kingdom has exactly one tram line. It has *n* stops, numbered from 1 to *n* in the order of tram's movement. At the *i*-th stop *a**i* passengers exit the tram, while *b**i* passengers enter it. The tram is empty before it arrives at the first stop. Also, when the tram arrives at the last stop, all passengers exit so that it becomes empty.
Your task is to calculate the tram's minimum capacity such that the number of people inside the tram at any time never exceeds this capacity. Note that at each stop all exiting passengers exit before any entering passenger enters the tram. | The first line contains a single number *n* (2<=≤<=*n*<=≤<=1000) — the number of the tram's stops.
Then *n* lines follow, each contains two integers *a**i* and *b**i* (0<=≤<=*a**i*,<=*b**i*<=≤<=1000) — the number of passengers that exits the tram at the *i*-th stop, and the number of passengers that enter the tram at the *i*-th stop. The stops are given from the first to the last stop in the order of tram's movement.
- The number of people who exit at a given stop does not exceed the total number of people in the tram immediately before it arrives at the stop. More formally, . This particularly means that *a*1<==<=0. - At the last stop, all the passengers exit the tram and it becomes empty. More formally, . - No passenger will enter the train at the last stop. That is, *b**n*<==<=0. | Print a single integer denoting the minimum possible capacity of the tram (0 is allowed). | [
"4\n0 3\n2 5\n4 2\n4 0\n"
] | [
"6\n"
] | For the first example, a capacity of 6 is sufficient:
- At the first stop, the number of passengers inside the tram before arriving is 0. Then, 3 passengers enter the tram, and the number of passengers inside the tram becomes 3. - At the second stop, 2 passengers exit the tram (1 passenger remains inside). Then, 5 passengers enter the tram. There are 6 passengers inside the tram now. - At the third stop, 4 passengers exit the tram (2 passengers remain inside). Then, 2 passengers enter the tram. There are 4 passengers inside the tram now. - Finally, all the remaining passengers inside the tram exit the tram at the last stop. There are no passenger inside the tram now, which is in line with the constraints.
Since the number of passengers inside the tram never exceeds 6, a capacity of 6 is sufficient. Furthermore it is not possible for the tram to have a capacity less than 6. Hence, 6 is the correct answer. | [
{
"input": "4\n0 3\n2 5\n4 2\n4 0",
"output": "6"
},
{
"input": "5\n0 4\n4 6\n6 5\n5 4\n4 0",
"output": "6"
},
{
"input": "10\n0 5\n1 7\n10 8\n5 3\n0 5\n3 3\n8 8\n0 6\n10 1\n9 0",
"output": "18"
},
{
"input": "3\n0 1\n1 1\n1 0",
"output": "1"
},
{
"input": "4\n0 1... | 60 | 0 | -1 | 1,272 | |
0 | none | [
"none"
] | null | null | A bracket sequence is a string, containing only characters "(", ")", "[" and "]".
A correct 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 correct (the resulting expressions are: "(1)+[1]", "([1+1]+1)"), and "](" and "[" are not. The empty string is a correct bracket sequence by definition.
A substring *s*[*l*... *r*] (1<=≤<=*l*<=≤<=*r*<=≤<=|*s*|) of string *s*<==<=*s*1*s*2... *s*|*s*| (where |*s*| is the length of string *s*) is the string *s**l**s**l*<=+<=1... *s**r*. The empty string is a substring of any string by definition.
You are given a bracket sequence, not necessarily correct. Find its substring which is a correct bracket sequence and contains as many opening square brackets «[» as possible. | The first and the only line contains the bracket sequence as a string, consisting only of characters "(", ")", "[" and "]". It is guaranteed that the string is non-empty and its length doesn't exceed 105 characters. | In the first line print a single integer — the number of brackets «[» in the required bracket sequence. In the second line print the optimal sequence. If there are more than one optimal solutions print any of them. | [
"([])\n",
"(((\n"
] | [
"1\n([])\n",
"0\n\n"
] | none | [
{
"input": "([])",
"output": "1\n([])"
},
{
"input": "(((",
"output": "0"
},
{
"input": "(][)",
"output": "0"
},
{
"input": "(()[))()[]",
"output": "1\n()[]"
},
{
"input": "(][](](][[(][",
"output": "1\n[]"
},
{
"input": "((])(]]))(](((()[[()[[[)([]()]... | 218 | 0 | 0 | 1,275 | |
522 | Reposts | [
"*special",
"dfs and similar",
"dp",
"graphs",
"trees"
] | null | null | One day Polycarp published a funny picture in a social network making a poll about the color of his handle. Many of his friends started reposting Polycarp's joke to their news feed. Some of them reposted the reposts and so on.
These events are given as a sequence of strings "name1 reposted name2", where name1 is the name of the person who reposted the joke, and name2 is the name of the person from whose news feed the joke was reposted. It is guaranteed that for each string "name1 reposted name2" user "name1" didn't have the joke in his feed yet, and "name2" already had it in his feed by the moment of repost. Polycarp was registered as "Polycarp" and initially the joke was only in his feed.
Polycarp measures the popularity of the joke as the length of the largest repost chain. Print the popularity of Polycarp's joke. | The first line of the input contains integer *n* (1<=≤<=*n*<=≤<=200) — the number of reposts. Next follow the reposts in the order they were made. Each of them is written on a single line and looks as "name1 reposted name2". All the names in the input consist of lowercase or uppercase English letters and/or digits and have lengths from 2 to 24 characters, inclusive.
We know that the user names are case-insensitive, that is, two names that only differ in the letter case correspond to the same social network user. | Print a single integer — the maximum length of a repost chain. | [
"5\ntourist reposted Polycarp\nPetr reposted Tourist\nWJMZBMR reposted Petr\nsdya reposted wjmzbmr\nvepifanov reposted sdya\n",
"6\nMike reposted Polycarp\nMax reposted Polycarp\nEveryOne reposted Polycarp\n111 reposted Polycarp\nVkCup reposted Polycarp\nCodeforces reposted Polycarp\n",
"1\nSoMeStRaNgEgUe repos... | [
"6\n",
"2\n",
"2\n"
] | none | [
{
"input": "5\ntourist reposted Polycarp\nPetr reposted Tourist\nWJMZBMR reposted Petr\nsdya reposted wjmzbmr\nvepifanov reposted sdya",
"output": "6"
},
{
"input": "6\nMike reposted Polycarp\nMax reposted Polycarp\nEveryOne reposted Polycarp\n111 reposted Polycarp\nVkCup reposted Polycarp\nCodeforc... | 46 | 0 | 0 | 1,277 | |
305 | Continued Fractions | [
"brute force",
"implementation",
"math"
] | null | null | A continued fraction of height *n* is a fraction of form . You are given two rational numbers, one is represented as and the other one is represented as a finite fraction of height *n*. Check if they are equal. | The first line contains two space-separated integers *p*,<=*q* (1<=≤<=*q*<=≤<=*p*<=≤<=1018) — the numerator and the denominator of the first fraction.
The second line contains integer *n* (1<=≤<=*n*<=≤<=90) — the height of the second fraction. The third line contains *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=1018) — the continued fraction.
Please, do not use the %lld specifier to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specifier. | Print "YES" if these fractions are equal and "NO" otherwise. | [
"9 4\n2\n2 4\n",
"9 4\n3\n2 3 1\n",
"9 4\n3\n1 2 4\n"
] | [
"YES\n",
"YES\n",
"NO\n"
] | In the first sample <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/5ff92f27aebea2560d99ad61202d20bab5ee5390.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
In the second sample <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/221368c79c05fc0ecad4e5f7a64f30b832fd99f5.png" style="max-width: 100.0%;max-height: 100.0%;"/>.
In the third sample <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/4fb4b411afc0fbad27a1c8fdd08ba88ec3830ef5.png" style="max-width: 100.0%;max-height: 100.0%;"/>. | [
{
"input": "9 4\n2\n2 4",
"output": "YES"
},
{
"input": "9 4\n3\n2 3 1",
"output": "YES"
},
{
"input": "9 4\n3\n1 2 4",
"output": "NO"
},
{
"input": "39088169 24157817\n36\n1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2",
"output": "YES"
},
{
... | 216 | 6,860,800 | 3 | 1,279 | |
665 | Simple Strings | [
"dp",
"greedy",
"strings"
] | null | null | zscoder loves simple strings! A string *t* is called simple if every pair of adjacent characters are distinct. For example ab, aba, zscoder are simple whereas aa, add are not simple.
zscoder is given a string *s*. He wants to change a minimum number of characters so that the string *s* becomes simple. Help him with this task! | The only line contains the string *s* (1<=≤<=|*s*|<=≤<=2·105) — the string given to zscoder. The string *s* consists of only lowercase English letters. | Print the simple string *s*' — the string *s* after the minimal number of changes. If there are multiple solutions, you may output any of them.
Note that the string *s*' should also consist of only lowercase English letters. | [
"aab\n",
"caaab\n",
"zscoder\n"
] | [
"bab\n",
"cabab\n",
"zscoder\n"
] | none | [
{
"input": "aab",
"output": "bab"
},
{
"input": "caaab",
"output": "cabab"
},
{
"input": "zscoder",
"output": "zscoder"
},
{
"input": "u",
"output": "u"
},
{
"input": "h",
"output": "h"
},
{
"input": "dtottttotd",
"output": "dtotataotd"
},
{
... | 139 | 43,520,000 | 3 | 1,281 | |
765 | Table Tennis Game 2 | [
"math"
] | null | null | Misha and Vanya have played several table tennis sets. Each set consists of several serves, each serve is won by one of the players, he receives one point and the loser receives nothing. Once one of the players scores exactly *k* points, the score is reset and a new set begins.
Across all the sets Misha scored *a* points in total, and Vanya scored *b* points. Given this information, determine the maximum number of sets they could have played, or that the situation is impossible.
Note that the game consisted of several complete sets. | The first line contains three space-separated integers *k*, *a* and *b* (1<=≤<=*k*<=≤<=109, 0<=≤<=*a*,<=*b*<=≤<=109, *a*<=+<=*b*<=><=0). | If the situation is impossible, print a single number -1. Otherwise, print the maximum possible number of sets. | [
"11 11 5\n",
"11 2 3\n"
] | [
"1\n",
"-1\n"
] | Note that the rules of the game in this problem differ from the real table tennis game, for example, the rule of "balance" (the winning player has to be at least two points ahead to win a set) has no power within the present problem. | [
{
"input": "11 11 5",
"output": "1"
},
{
"input": "11 2 3",
"output": "-1"
},
{
"input": "1 5 9",
"output": "14"
},
{
"input": "2 3 3",
"output": "2"
},
{
"input": "1 1000000000 1000000000",
"output": "2000000000"
},
{
"input": "2 3 5",
"output": "... | 61 | 0 | 0 | 1,282 | |
93 | Lostborn | [
"dp",
"math",
"number theory"
] | E. Lostborn | 2 | 256 | Igor K. very much likes a multiplayer role playing game WineAge II. Who knows, perhaps, that might be the reason for his poor performance at the university. As any person who plays the game, he is interested in equipping his hero with as good weapon and outfit as possible.
One day, as he was reading the game's forum yet again, he discovered a very interesting fact. As it turns out, each weapon in the game is characterised with *k* different numbers: *a*1,<=...,<=*a**k*. They are called hit indicators and according to the game developers' plan they are pairwise coprime.
The damage that is inflicted during a hit depends not only on the weapon's characteristics, but also on the hero's strength parameter. Thus, if the hero's strength equals *n*, than the inflicted damage will be calculated as the number of numbers on the segment , that aren't divisible by any hit indicator *a**i*.
Recently, having fulfilled another quest, Igor K. found a new Lostborn sword. He wants to know how much damage he will inflict upon his enemies if he uses it. | The first line contains two integers: *n* and *k* (1<=≤<=*n*<=≤<=1013, 1<=≤<=*k*<=≤<=100). They are the indicator of Igor K's hero's strength and the number of hit indicators.
The next line contains space-separated *k* integers *a**i* (1<=≤<=*a**i*<=≤<=1000). They are Lostborn sword's hit indicators. The given *k* numbers are pairwise coprime. | Print the single number — the damage that will be inflicted by Igor K.'s hero when he uses his new weapon.
Please, do not use the %lld specificator to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams or the %I64d specificator. | [
"20 3\n2 3 5\n",
"50 2\n15 8\n"
] | [
"6\n",
"41\n"
] | none | [] | 2,000 | 10,240,000 | 0 | 1,283 |
845 | Two TVs | [
"data structures",
"greedy",
"sortings"
] | null | null | Polycarp is a great fan of television.
He wrote down all the TV programs he is interested in for today. His list contains *n* shows, *i*-th of them starts at moment *l**i* and ends at moment *r**i*.
Polycarp owns two TVs. He can watch two different shows simultaneously with two TVs but he can only watch one show at any given moment on a single TV. If one show ends at the same moment some other show starts then you can't watch them on a single TV.
Polycarp wants to check out all *n* shows. Are two TVs enough to do so? | The first line contains one integer *n* (1<=≤<=*n*<=≤<=2·105) — the number of shows.
Each of the next *n* lines contains two integers *l**i* and *r**i* (0<=≤<=*l**i*<=<<=*r**i*<=≤<=109) — starting and ending time of *i*-th show. | If Polycarp is able to check out all the shows using only two TVs then print "YES" (without quotes). Otherwise, print "NO" (without quotes). | [
"3\n1 2\n2 3\n4 5\n",
"4\n1 2\n2 3\n2 3\n1 2\n"
] | [
"YES\n",
"NO\n"
] | none | [
{
"input": "3\n1 2\n2 3\n4 5",
"output": "YES"
},
{
"input": "4\n1 2\n2 3\n2 3\n1 2",
"output": "NO"
},
{
"input": "4\n0 1\n1 2\n2 3\n3 4",
"output": "YES"
},
{
"input": "3\n1 2\n2 3\n2 4",
"output": "NO"
},
{
"input": "3\n0 100\n0 100\n0 100",
"output": "NO"
... | 1,107 | 22,835,200 | 0 | 1,284 | |
689 | Mike and Cellphone | [
"brute force",
"constructive algorithms",
"implementation"
] | null | null | While swimming at the beach, Mike has accidentally dropped his cellphone into the water. There was no worry as he bought a cheap replacement phone with an old-fashioned keyboard. The keyboard has only ten digital equal-sized keys, located in the following way:
Together with his old phone, he lost all his contacts and now he can only remember the way his fingers moved when he put some number in. One can formally consider finger movements as a sequence of vectors connecting centers of keys pressed consecutively to put in a number. For example, the finger movements for number "586" are the same as finger movements for number "253":
Mike has already put in a number by his "finger memory" and started calling it, so he is now worrying, can he be sure that he is calling the correct number? In other words, is there any other number, that has the same finger movements? | The first line of the input contains the only integer *n* (1<=≤<=*n*<=≤<=9) — the number of digits in the phone number that Mike put in.
The second line contains the string consisting of *n* digits (characters from '0' to '9') representing the number that Mike put in. | If there is no other phone number with the same finger movements and Mike can be sure he is calling the correct number, print "YES" (without quotes) in the only line.
Otherwise print "NO" (without quotes) in the first line. | [
"3\n586\n",
"2\n09\n",
"9\n123456789\n",
"3\n911\n"
] | [
"NO\n",
"NO\n",
"YES\n",
"YES\n"
] | You can find the picture clarifying the first sample case in the statement above. | [
{
"input": "3\n586",
"output": "NO"
},
{
"input": "2\n09",
"output": "NO"
},
{
"input": "9\n123456789",
"output": "YES"
},
{
"input": "3\n911",
"output": "YES"
},
{
"input": "3\n089",
"output": "NO"
},
{
"input": "3\n159",
"output": "YES"
},
{
... | 140 | 0 | 3 | 1,285 | |
39 | Pacifist frogs | [
"implementation"
] | F. Pacifist frogs | 2 | 64 | Thumbelina has had an accident. She has found herself on a little island in the middle of a swamp and wants to get to the shore very much.
One can get to the shore only by hills that are situated along a straight line that connects the little island with the shore. Let us assume that the hills are numbered from 1 to *n* and the number of a hill is equal to the distance in meters between it and the island. The distance between the *n*-th hill and the shore is also 1 meter.
Thumbelina is too small to make such jumps. Fortunately, a family of frogs living in the swamp suggests to help her. Each frog agrees to give Thumbelina a ride but Thumbelina should choose only one frog. Each frog has a certain jump length. If Thumbelina agrees to accept help from a frog whose jump length is *d*, the frog will jump from the island on the hill *d*, then — on the hill 2*d*, then 3*d* and so on until they get to the shore (i.e. find itself beyond the hill *n*).
However, there is one more problem: mosquitoes also live in the swamp. At the moment they have a siesta, and they are having a nap on some hills. If the frog jumps on a hill with a mosquito the frog will smash it. The frogs Thumbelina has met are pacifists, so they will find the death of each mosquito very much sad. Help Thumbelina choose a frog that will bring her to the shore and smash as small number of mosquitoes as possible. | The first line contains three integers *n*, *m* and *k* (1<=≤<=*n*<=≤<=109, 1<=≤<=*m*,<=*k*<=≤<=100) — the number of hills, frogs and mosquitoes respectively. The second line contains *m* integers *d**i* (1<=≤<=*d**i*<=≤<=109) — the lengths of the frogs’ jumps. The third line contains *k* integers — the numbers of the hills on which each mosquito is sleeping. No more than one mosquito can sleep on each hill. The numbers in the lines are separated by single spaces. | In the first line output the number of frogs that smash the minimal number of mosquitoes, in the second line — their numbers in increasing order separated by spaces. The frogs are numbered from 1 to *m* in the order of the jump length given in the input data. | [
"5 3 5\n2 3 4\n1 2 3 4 5\n",
"1000000000 2 3\n2 5\n999999995 999999998 999999996\n"
] | [
"2\n2 3\n",
"1\n2\n"
] | none | [
{
"input": "5 3 5\n2 3 4\n1 2 3 4 5",
"output": "2\n2 3"
},
{
"input": "1000000000 2 3\n2 5\n999999995 999999998 999999996",
"output": "1\n2"
},
{
"input": "1 1 1\n1\n1",
"output": "1\n1"
},
{
"input": "2 2 1\n2 1\n1",
"output": "1\n1"
},
{
"input": "3 2 2\n2 4\n3... | 218 | 307,200 | 3.943211 | 1,287 |
538 | Quasi Binary | [
"constructive algorithms",
"dp",
"greedy",
"implementation"
] | null | null | A number is called quasibinary if its decimal representation contains only digits 0 or 1. For example, numbers 0, 1, 101, 110011 — are quasibinary and numbers 2, 12, 900 are not.
You are given a positive integer *n*. Represent it as a sum of minimum number of quasibinary numbers. | The first line contains a single integer *n* (1<=≤<=*n*<=≤<=106). | In the first line print a single integer *k* — the minimum number of numbers in the representation of number *n* as a sum of quasibinary numbers.
In the second line print *k* numbers — the elements of the sum. All these numbers should be quasibinary according to the definition above, their sum should equal *n*. Do not have to print the leading zeroes in the numbers. The order of numbers doesn't matter. If there are multiple possible representations, you are allowed to print any of them. | [
"9\n",
"32\n"
] | [
"9\n1 1 1 1 1 1 1 1 1 \n",
"3\n10 11 11 \n"
] | none | [
{
"input": "9",
"output": "9\n1 1 1 1 1 1 1 1 1 "
},
{
"input": "32",
"output": "3\n10 11 11 "
},
{
"input": "1",
"output": "1\n1 "
},
{
"input": "415",
"output": "5\n1 101 101 101 111 "
},
{
"input": "10011",
"output": "1\n10011 "
},
{
"input": "10201... | 124 | 0 | 0 | 1,290 | |
435 | Pasha Maximizes | [
"greedy"
] | null | null | Pasha has a positive integer *a* without leading zeroes. Today he decided that the number is too small and he should make it larger. Unfortunately, the only operation Pasha can do is to swap two adjacent decimal digits of the integer.
Help Pasha count the maximum number he can get if he has the time to make at most *k* swaps. | The single line contains two integers *a* and *k* (1<=≤<=*a*<=≤<=1018; 0<=≤<=*k*<=≤<=100). | Print the maximum number that Pasha can get if he makes at most *k* swaps. | [
"1990 1\n",
"300 0\n",
"1034 2\n",
"9090000078001234 6\n"
] | [
"9190\n",
"300\n",
"3104\n",
"9907000008001234\n"
] | none | [
{
"input": "1990 1",
"output": "9190"
},
{
"input": "300 0",
"output": "300"
},
{
"input": "1034 2",
"output": "3104"
},
{
"input": "9090000078001234 6",
"output": "9907000008001234"
},
{
"input": "1234 3",
"output": "4123"
},
{
"input": "5 100",
"... | 46 | 0 | 0 | 1,292 | |
109 | Lucky Sum of Digits | [
"brute force",
"implementation"
] | A. Lucky Sum of Digits | 2 | 256 | Petya loves lucky numbers. We all know that lucky numbers are the positive integers whose decimal representations contain only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.
Petya wonders eagerly what minimum lucky number has the sum of digits equal to *n*. Help him cope with the task. | The single line contains an integer *n* (1<=≤<=*n*<=≤<=106) — the sum of digits of the required lucky number. | Print on the single line the result — the minimum lucky number, whose sum of digits equals *n*. If such number does not exist, print -1. | [
"11\n",
"10\n"
] | [
"47\n",
"-1\n"
] | none | [
{
"input": "11",
"output": "47"
},
{
"input": "10",
"output": "-1"
},
{
"input": "64",
"output": "4477777777"
},
{
"input": "1",
"output": "-1"
},
{
"input": "4",
"output": "4"
},
{
"input": "7",
"output": "7"
},
{
"input": "12",
"outpu... | 92 | 6,656,000 | 0 | 1,294 |
295 | Greg and Graph | [
"dp",
"graphs",
"shortest paths"
] | null | null | Greg has a weighed directed graph, consisting of *n* vertices. In this graph any pair of distinct vertices has an edge between them in both directions. Greg loves playing with the graph and now he has invented a new game:
- The game consists of *n* steps. - On the *i*-th step Greg removes vertex number *x**i* from the graph. As Greg removes a vertex, he also removes all the edges that go in and out of this vertex. - Before executing each step, Greg wants to know the sum of lengths of the shortest paths between all pairs of the remaining vertices. The shortest path can go through any remaining vertex. In other words, if we assume that *d*(*i*,<=*v*,<=*u*) is the shortest path between vertices *v* and *u* in the graph that formed before deleting vertex *x**i*, then Greg wants to know the value of the following sum: .
Help Greg, print the value of the required sum before each step. | The first line contains integer *n* (1<=≤<=*n*<=≤<=500) — the number of vertices in the graph.
Next *n* lines contain *n* integers each — the graph adjacency matrix: the *j*-th number in the *i*-th line *a**ij* (1<=≤<=*a**ij*<=≤<=105,<=*a**ii*<==<=0) represents the weight of the edge that goes from vertex *i* to vertex *j*.
The next line contains *n* distinct integers: *x*1,<=*x*2,<=...,<=*x**n* (1<=≤<=*x**i*<=≤<=*n*) — the vertices that Greg deletes. | Print *n* integers — the *i*-th number equals the required sum before the *i*-th step.
Please, do not use the %lld specifier to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams of the %I64d specifier. | [
"1\n0\n1\n",
"2\n0 5\n4 0\n1 2\n",
"4\n0 3 1 1\n6 0 400 1\n2 4 0 1\n1 1 1 0\n4 1 2 3\n"
] | [
"0 ",
"9 0 ",
"17 23 404 0 "
] | none | [
{
"input": "1\n0\n1",
"output": "0 "
},
{
"input": "2\n0 5\n4 0\n1 2",
"output": "9 0 "
},
{
"input": "4\n0 3 1 1\n6 0 400 1\n2 4 0 1\n1 1 1 0\n4 1 2 3",
"output": "17 23 404 0 "
},
{
"input": "4\n0 57148 51001 13357\n71125 0 98369 67226\n49388 90852 0 66291\n39573 38165 9700... | 3,000 | 8,499,200 | 0 | 1,296 | |
542 | Idempotent functions | [
"constructive algorithms",
"graphs",
"math"
] | null | null | Some time ago Leonid have known about idempotent functions. Idempotent function defined on a set {1,<=2,<=...,<=*n*} is such function , that for any the formula *g*(*g*(*x*))<==<=*g*(*x*) holds.
Let's denote as *f*(*k*)(*x*) the function *f* applied *k* times to the value *x*. More formally, *f*(1)(*x*)<==<=*f*(*x*), *f*(*k*)(*x*)<==<=*f*(*f*(*k*<=-<=1)(*x*)) for each *k*<=><=1.
You are given some function . Your task is to find minimum positive integer *k* such that function *f*(*k*)(*x*) is idempotent. | In the first line of the input there is a single integer *n* (1<=≤<=*n*<=≤<=200) — the size of function *f* domain.
In the second line follow *f*(1),<=*f*(2),<=...,<=*f*(*n*) (1<=≤<=*f*(*i*)<=≤<=*n* for each 1<=≤<=*i*<=≤<=*n*), the values of a function. | Output minimum *k* such that function *f*(*k*)(*x*) is idempotent. | [
"4\n1 2 2 4\n",
"3\n2 3 3\n",
"3\n2 3 1\n"
] | [
"1\n",
"2\n",
"3\n"
] | In the first sample test function *f*(*x*) = *f*<sup class="upper-index">(1)</sup>(*x*) is already idempotent since *f*(*f*(1)) = *f*(1) = 1, *f*(*f*(2)) = *f*(2) = 2, *f*(*f*(3)) = *f*(3) = 2, *f*(*f*(4)) = *f*(4) = 4.
In the second sample test:
- function *f*(*x*) = *f*<sup class="upper-index">(1)</sup>(*x*) isn't idempotent because *f*(*f*(1)) = 3 but *f*(1) = 2; - function *f*(*x*) = *f*<sup class="upper-index">(2)</sup>(*x*) is idempotent since for any *x* it is true that *f*<sup class="upper-index">(2)</sup>(*x*) = 3, so it is also true that *f*<sup class="upper-index">(2)</sup>(*f*<sup class="upper-index">(2)</sup>(*x*)) = 3.
In the third sample test:
- function *f*(*x*) = *f*<sup class="upper-index">(1)</sup>(*x*) isn't idempotent because *f*(*f*(1)) = 3 but *f*(1) = 2; - function *f*(*f*(*x*)) = *f*<sup class="upper-index">(2)</sup>(*x*) isn't idempotent because *f*<sup class="upper-index">(2)</sup>(*f*<sup class="upper-index">(2)</sup>(1)) = 2 but *f*<sup class="upper-index">(2)</sup>(1) = 3; - function *f*(*f*(*f*(*x*))) = *f*<sup class="upper-index">(3)</sup>(*x*) is idempotent since it is identity function: *f*<sup class="upper-index">(3)</sup>(*x*) = *x* for any <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/46a8c73444c646004dfde04451775e7af924d108.png" style="max-width: 100.0%;max-height: 100.0%;"/> meaning that the formula *f*<sup class="upper-index">(3)</sup>(*f*<sup class="upper-index">(3)</sup>(*x*)) = *f*<sup class="upper-index">(3)</sup>(*x*) also holds. | [
{
"input": "4\n1 2 2 4",
"output": "1"
},
{
"input": "3\n2 3 3",
"output": "2"
},
{
"input": "3\n2 3 1",
"output": "3"
},
{
"input": "1\n1",
"output": "1"
},
{
"input": "16\n1 4 13 9 11 16 14 6 5 12 7 8 15 2 3 10",
"output": "105"
},
{
"input": "20\n1 ... | 93 | 0 | 3 | 1,297 | |
89 | Fire and Ice | [
"greedy"
] | E. Fire and Ice | 0 | 256 | The Fire Lord attacked the Frost Kingdom. He has already got to the Ice Fortress, where the Snow Queen dwells. He arranged his army on a segment *n* in length not far from the city walls. And only the frost magician Solomon can save the Frost Kingdom.
The *n*-long segment is located at a distance equal exactly to 1 from the castle walls. It can be imaginarily divided into unit segments. On some of the unit segments fire demons are located — no more than one demon per position. Each demon is characterised by his strength - by some positive integer. We can regard the fire demons being idle.
Initially Solomon is positioned on the fortress wall. He can perform the following actions several times in a row:
- "L" — Solomon shifts one unit to the left. This movement cannot be performed on the castle wall.- "R" — Solomon shifts one unit to the left. This movement cannot be performed if there's no ice block to the right.- "A" — If there's nothing to the right of Solomon, then Solomon creates an ice block that immediately freezes to the block that Solomon is currently standing on. If there already is an ice block, then Solomon destroys it. At that the ice blocks to the right of the destroyed one can remain but they are left unsupported. Those ice blocks fall down.
Solomon spends exactly a second on each of these actions.
As the result of Solomon's actions, ice blocks' segments fall down. When an ice block falls on a fire demon, the block evaporates and the demon's strength is reduced by 1. When the demons' strength is equal to 0, the fire demon vanishes. The picture below shows how it happens. The ice block that falls on the position with no demon, breaks into lots of tiny pieces and vanishes without hurting anybody.
Help Solomon destroy all the Fire Lord's army in minimum time. | The first line contains an integer *n* (1<=≤<=*n*<=≤<=1000). The next line contains *n* numbers, the *i*-th of them represents the strength of the fire demon standing of the *i*-th position, an integer from 1 to 100. If there's no demon on the *i*-th position, then the *i*-th number equals to 0. It is guaranteed that the input data have at least one fire demon. | Print a string of minimum length, containing characters "L", "R" and "A" — the succession of actions leading to the required result.
If there are several possible answers, print any of them. | [
"3\n1 0 1\n",
"3\n0 2 0\n"
] | [
"ARARARALLLA",
"ARARALAARALA"
] | none | [
{
"input": "3\n1 0 1",
"output": "ARARARALLLA"
},
{
"input": "3\n0 2 0",
"output": "ARARALAARALA"
},
{
"input": "5\n3 1 2 2 4",
"output": "ARALAARALAARARARARARALLLAARARARALAARALAARALLLLLA"
},
{
"input": "4\n2 2 2 2",
"output": "ARARARARALLLLAARARARARALLLLA"
},
{
"... | 46 | 0 | 0 | 1,299 |
245 | Game with Coins | [
"greedy"
] | null | null | Two pirates Polycarpus and Vasily play a very interesting game. They have *n* chests with coins, the chests are numbered with integers from 1 to *n*. Chest number *i* has *a**i* coins.
Polycarpus and Vasily move in turns. Polycarpus moves first. During a move a player is allowed to choose a positive integer *x* (2·*x*<=+<=1<=≤<=*n*) and take a coin from each chest with numbers *x*, 2·*x*, 2·*x*<=+<=1. It may turn out that some chest has no coins, in this case the player doesn't take a coin from this chest. The game finishes when all chests get emptied.
Polycarpus isn't a greedy scrooge. Polycarpys is a lazy slob. So he wonders in what minimum number of moves the game can finish. Help Polycarpus, determine the minimum number of moves in which the game can finish. Note that Polycarpus counts not only his moves, he also counts Vasily's moves. | The first line contains a single integer *n* (1<=≤<=*n*<=≤<=100) — the number of chests with coins. The second line contains a sequence of space-separated integers: *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=1000), where *a**i* is the number of coins in the chest number *i* at the beginning of the game. | Print a single integer — the minimum number of moves needed to finish the game. If no sequence of turns leads to finishing the game, print -1. | [
"1\n1\n",
"3\n1 2 3\n"
] | [
"-1\n",
"3\n"
] | In the first test case there isn't a single move that can be made. That's why the players won't be able to empty the chests.
In the second sample there is only one possible move *x* = 1. This move should be repeated at least 3 times to empty the third chest. | [
{
"input": "1\n1",
"output": "-1"
},
{
"input": "3\n1 2 3",
"output": "3"
},
{
"input": "100\n269 608 534 956 993 409 297 735 258 451 468 422 125 407 580 769 857 383 419 67 377 230 842 113 169 427 287 75 372 133 456 450 644 303 638 40 217 445 427 730 168 341 371 633 237 951 142 596 528 5... | 278 | 20,172,800 | 0 | 1,302 | |
137 | Postcards and photos | [
"implementation"
] | null | null | Polycarpus has postcards and photos hung in a row on the wall. He decided to put them away to the closet and hang on the wall a famous painter's picture. Polycarpus does it like that: he goes from the left to the right and removes the objects consecutively. As Polycarpus doesn't want any mix-ups to happen, he will not carry in his hands objects of two different types. In other words, Polycarpus can't carry both postcards and photos simultaneously. Sometimes he goes to the closet and puts the objects there, thus leaving his hands free. Polycarpus must put all the postcards and photos to the closet. He cannot skip objects. What minimum number of times he should visit the closet if he cannot carry more than 5 items? | The only line of the input data contains a non-empty string consisting of letters "С" and "P" whose length does not exceed 100 characters. If the *i*-th character in the string is the letter "С", that means that the *i*-th object (the numbering goes from the left to the right) on Polycarpus' wall is a postcard. And if the *i*-th character is the letter "P", than the *i*-th object on the wall is a photo. | Print the only number — the minimum number of times Polycarpus has to visit the closet. | [
"CPCPCPC\n",
"CCCCCCPPPPPP\n",
"CCCCCCPPCPPPPPPPPPP\n",
"CCCCCCCCCC\n"
] | [
"7\n",
"4\n",
"6\n",
"2\n"
] | In the first sample Polycarpus needs to take one item to the closet 7 times.
In the second sample Polycarpus can first take 3 postcards to the closet; then 3 more. He can take the 6 photos that are left in the similar way, going to the closet twice.
In the third sample Polycarpus can visit the closet twice, both times carrying 3 postcards. Then he can take there 2 photos at once, then one postcard and finally, he can carry the last 10 photos if he visits the closet twice.
In the fourth sample Polycarpus can visit the closet twice and take there all 10 postcards (5 items during each go). | [
{
"input": "CPCPCPC",
"output": "7"
},
{
"input": "CCCCCCPPPPPP",
"output": "4"
},
{
"input": "CCCCCCPPCPPPPPPPPPP",
"output": "6"
},
{
"input": "CCCCCCCCCC",
"output": "2"
},
{
"input": "CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC... | 218 | 307,200 | 0 | 1,304 | |
637 | Voting for Photos | [
"*special",
"constructive algorithms",
"implementation"
] | null | null | After celebrating the midcourse the students of one of the faculties of the Berland State University decided to conduct a vote for the best photo. They published the photos in the social network and agreed on the rules to choose a winner: the photo which gets most likes wins. If multiple photoes get most likes, the winner is the photo that gets this number first.
Help guys determine the winner photo by the records of likes. | The first line of the input contains a single integer *n* (1<=≤<=*n*<=≤<=1000) — the total likes to the published photoes.
The second line contains *n* positive integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=1<=000<=000), where *a**i* is the identifier of the photo which got the *i*-th like. | Print the identifier of the photo which won the elections. | [
"5\n1 3 2 2 1\n",
"9\n100 200 300 200 100 300 300 100 200\n"
] | [
"2\n",
"300\n"
] | In the first test sample the photo with id 1 got two likes (first and fifth), photo with id 2 got two likes (third and fourth), and photo with id 3 got one like (second).
Thus, the winner is the photo with identifier 2, as it got:
- more likes than the photo with id 3; - as many likes as the photo with id 1, but the photo with the identifier 2 got its second like earlier. | [
{
"input": "5\n1 3 2 2 1",
"output": "2"
},
{
"input": "9\n100 200 300 200 100 300 300 100 200",
"output": "300"
},
{
"input": "1\n5",
"output": "5"
},
{
"input": "1\n1000000",
"output": "1000000"
},
{
"input": "5\n1 3 4 2 2",
"output": "2"
},
{
"input... | 77 | 819,200 | 3 | 1,308 | |
371 | Hamburgers | [
"binary search",
"brute force"
] | null | null | Polycarpus loves hamburgers very much. He especially adores the hamburgers he makes with his own hands. Polycarpus thinks that there are only three decent ingredients to make hamburgers from: a bread, sausage and cheese. He writes down the recipe of his favorite "Le Hamburger de Polycarpus" as a string of letters 'B' (bread), 'S' (sausage) и 'C' (cheese). The ingredients in the recipe go from bottom to top, for example, recipe "ВSCBS" represents the hamburger where the ingredients go from bottom to top as bread, sausage, cheese, bread and sausage again.
Polycarpus has *n**b* pieces of bread, *n**s* pieces of sausage and *n**c* pieces of cheese in the kitchen. Besides, the shop nearby has all three ingredients, the prices are *p**b* rubles for a piece of bread, *p**s* for a piece of sausage and *p**c* for a piece of cheese.
Polycarpus has *r* rubles and he is ready to shop on them. What maximum number of hamburgers can he cook? You can assume that Polycarpus cannot break or slice any of the pieces of bread, sausage or cheese. Besides, the shop has an unlimited number of pieces of each ingredient. | The first line of the input contains a non-empty string that describes the recipe of "Le Hamburger de Polycarpus". The length of the string doesn't exceed 100, the string contains only letters 'B' (uppercase English B), 'S' (uppercase English S) and 'C' (uppercase English C).
The second line contains three integers *n**b*, *n**s*, *n**c* (1<=≤<=*n**b*,<=*n**s*,<=*n**c*<=≤<=100) — the number of the pieces of bread, sausage and cheese on Polycarpus' kitchen. The third line contains three integers *p**b*, *p**s*, *p**c* (1<=≤<=*p**b*,<=*p**s*,<=*p**c*<=≤<=100) — the price of one piece of bread, sausage and cheese in the shop. Finally, the fourth line contains integer *r* (1<=≤<=*r*<=≤<=1012) — the number of rubles Polycarpus has.
Please, do not write the %lld specifier to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specifier. | Print the maximum number of hamburgers Polycarpus can make. If he can't make any hamburger, print 0. | [
"BBBSSC\n6 4 1\n1 2 3\n4\n",
"BBC\n1 10 1\n1 10 1\n21\n",
"BSC\n1 1 1\n1 1 3\n1000000000000\n"
] | [
"2\n",
"7\n",
"200000000001\n"
] | none | [
{
"input": "BBBSSC\n6 4 1\n1 2 3\n4",
"output": "2"
},
{
"input": "BBC\n1 10 1\n1 10 1\n21",
"output": "7"
},
{
"input": "BSC\n1 1 1\n1 1 3\n1000000000000",
"output": "200000000001"
},
{
"input": "B\n1 1 1\n1 1 1\n381",
"output": "382"
},
{
"input": "BSC\n3 5 6\n7... | 15 | 0 | -1 | 1,309 | |
437 | The Child and Toy | [
"graphs",
"greedy",
"sortings"
] | null | null | On Children's Day, the child got a toy from Delayyy as a present. However, the child is so naughty that he can't wait to destroy the toy.
The toy consists of *n* parts and *m* ropes. Each rope links two parts, but every pair of parts is linked by at most one rope. To split the toy, the child must remove all its parts. The child can remove a single part at a time, and each remove consume an energy. Let's define an energy value of part *i* as *v**i*. The child spend *v**f*1<=+<=*v**f*2<=+<=...<=+<=*v**f**k* energy for removing part *i* where *f*1,<=*f*2,<=...,<=*f**k* are the parts that are directly connected to the *i*-th and haven't been removed.
Help the child to find out, what is the minimum total energy he should spend to remove all *n* parts. | The first line contains two integers *n* and *m* (1<=≤<=*n*<=≤<=1000; 0<=≤<=*m*<=≤<=2000). The second line contains *n* integers: *v*1,<=*v*2,<=...,<=*v**n* (0<=≤<=*v**i*<=≤<=105). Then followed *m* lines, each line contains two integers *x**i* and *y**i*, representing a rope from part *x**i* to part *y**i* (1<=≤<=*x**i*,<=*y**i*<=≤<=*n*; *x**i*<=≠<=*y**i*).
Consider all the parts are numbered from 1 to *n*. | Output the minimum total energy the child should spend to remove all *n* parts of the toy. | [
"4 3\n10 20 30 40\n1 4\n1 2\n2 3\n",
"4 4\n100 100 100 100\n1 2\n2 3\n2 4\n3 4\n",
"7 10\n40 10 20 10 20 80 40\n1 5\n4 7\n4 5\n5 2\n5 7\n6 4\n1 6\n1 3\n4 3\n1 4\n"
] | [
"40\n",
"400\n",
"160\n"
] | One of the optimal sequence of actions in the first sample is:
- First, remove part 3, cost of the action is 20. - Then, remove part 2, cost of the action is 10. - Next, remove part 4, cost of the action is 10. - At last, remove part 1, cost of the action is 0.
So the total energy the child paid is 20 + 10 + 10 + 0 = 40, which is the minimum.
In the second sample, the child will spend 400 no matter in what order he will remove the parts. | [
{
"input": "4 3\n10 20 30 40\n1 4\n1 2\n2 3",
"output": "40"
},
{
"input": "4 4\n100 100 100 100\n1 2\n2 3\n2 4\n3 4",
"output": "400"
},
{
"input": "7 10\n40 10 20 10 20 80 40\n1 5\n4 7\n4 5\n5 2\n5 7\n6 4\n1 6\n1 3\n4 3\n1 4",
"output": "160"
},
{
"input": "1 0\n23333",
... | 62 | 0 | -1 | 1,310 | |
908 | New Year and Counting Cards | [
"brute force",
"implementation"
] | null | null | Your friend has *n* cards.
You know that each card has a lowercase English letter on one side and a digit on the other.
Currently, your friend has laid out the cards on a table so only one side of each card is visible.
You would like to know if the following statement is true for cards that your friend owns: "If a card has a vowel on one side, then it has an even digit on the other side." More specifically, a vowel is one of 'a', 'e', 'i', 'o' or 'u', and even digit is one of '0', '2', '4', '6' or '8'.
For example, if a card has 'a' on one side, and '6' on the other side, then this statement is true for it. Also, the statement is true, for example, for a card with 'b' and '4', and for a card with 'b' and '3' (since the letter is not a vowel). The statement is false, for example, for card with 'e' and '5'. You are interested if the statement is true for all cards. In particular, if no card has a vowel, the statement is true.
To determine this, you can flip over some cards to reveal the other side. You would like to know what is the minimum number of cards you need to flip in the worst case in order to verify that the statement is true. | The first and only line of input will contain a string *s* (1<=≤<=|*s*|<=≤<=50), denoting the sides of the cards that you can see on the table currently. Each character of *s* is either a lowercase English letter or a digit. | Print a single integer, the minimum number of cards you must turn over to verify your claim. | [
"ee\n",
"z\n",
"0ay1\n"
] | [
"2\n",
"0\n",
"2\n"
] | In the first sample, we must turn over both cards. Note that even though both cards have the same letter, they could possibly have different numbers on the other side.
In the second sample, we don't need to turn over any cards. The statement is vacuously true, since you know your friend has no cards with a vowel on them.
In the third sample, we need to flip the second and fourth cards. | [
{
"input": "ee",
"output": "2"
},
{
"input": "z",
"output": "0"
},
{
"input": "0ay1",
"output": "2"
},
{
"input": "0abcdefghijklmnopqrstuvwxyz1234567896",
"output": "10"
},
{
"input": "0a0a9e9e2i2i9o9o6u6u9z9z4x4x9b9b",
"output": "18"
},
{
"input": "01... | 109 | 0 | 3 | 1,312 | |
574 | Bear and Three Musketeers | [
"brute force",
"dfs and similar",
"graphs",
"hashing"
] | null | null | Do you know a story about the three musketeers? Anyway, you will learn about its origins now.
Richelimakieu is a cardinal in the city of Bearis. He is tired of dealing with crime by himself. He needs three brave warriors to help him to fight against bad guys.
There are *n* warriors. Richelimakieu wants to choose three of them to become musketeers but it's not that easy. The most important condition is that musketeers must know each other to cooperate efficiently. And they shouldn't be too well known because they could be betrayed by old friends. For each musketeer his recognition is the number of warriors he knows, excluding other two musketeers.
Help Richelimakieu! Find if it is possible to choose three musketeers knowing each other, and what is minimum possible sum of their recognitions. | The first line contains two space-separated integers, *n* and *m* (3<=≤<=*n*<=≤<=4000, 0<=≤<=*m*<=≤<=4000) — respectively number of warriors and number of pairs of warriors knowing each other.
*i*-th of the following *m* lines contains two space-separated integers *a**i* and *b**i* (1<=≤<=*a**i*,<=*b**i*<=≤<=*n*, *a**i*<=≠<=*b**i*). Warriors *a**i* and *b**i* know each other. Each pair of warriors will be listed at most once. | If Richelimakieu can choose three musketeers, print the minimum possible sum of their recognitions. Otherwise, print "-1" (without the quotes). | [
"5 6\n1 2\n1 3\n2 3\n2 4\n3 4\n4 5\n",
"7 4\n2 1\n3 6\n5 1\n1 7\n"
] | [
"2\n",
"-1\n"
] | In the first sample Richelimakieu should choose a triple 1, 2, 3. The first musketeer doesn't know anyone except other two musketeers so his recognition is 0. The second musketeer has recognition 1 because he knows warrior number 4. The third musketeer also has recognition 1 because he knows warrior 4. Sum of recognitions is 0 + 1 + 1 = 2.
The other possible triple is 2, 3, 4 but it has greater sum of recognitions, equal to 1 + 1 + 1 = 3.
In the second sample there is no triple of warriors knowing each other. | [
{
"input": "5 6\n1 2\n1 3\n2 3\n2 4\n3 4\n4 5",
"output": "2"
},
{
"input": "7 4\n2 1\n3 6\n5 1\n1 7",
"output": "-1"
},
{
"input": "5 0",
"output": "-1"
},
{
"input": "7 14\n3 6\n2 3\n5 2\n5 6\n7 5\n7 4\n6 2\n3 5\n7 1\n4 1\n6 1\n7 6\n6 4\n5 4",
"output": "5"
},
{
... | 904 | 3,584,000 | 0 | 1,322 | |
227 | Where do I Turn? | [
"geometry"
] | null | null | Trouble came from the overseas lands: a three-headed dragon Gorynych arrived. The dragon settled at point *C* and began to terrorize the residents of the surrounding villages.
A brave hero decided to put an end to the dragon. He moved from point *A* to fight with Gorynych. The hero rode from point *A* along a straight road and met point *B* on his way. The hero knows that in this land for every pair of roads it is true that they are either parallel to each other, or lie on a straight line, or are perpendicular to each other. He also knows well that points *B* and *C* are connected by a road. So the hero must either turn 90 degrees to the left or continue riding straight ahead or turn 90 degrees to the right. But he forgot where the point *C* is located.
Fortunately, a Brave Falcon flew right by. It can see all three points from the sky. The hero asked him what way to go to get to the dragon's lair.
If you have not got it, you are the falcon. Help the hero and tell him how to get him to point *C*: turn left, go straight or turn right.
At this moment the hero is believed to stand at point *B*, turning his back to point *A*. | The first input line contains two space-separated integers *x**a*,<=*y**a* (|*x**a*|,<=|*y**a*|<=≤<=109) — the coordinates of point *A*. The second line contains the coordinates of point *B* in the same form, the third line contains the coordinates of point *C*.
It is guaranteed that all points are pairwise different. It is also guaranteed that either point *B* lies on segment *AC*, or angle *ABC* is right. | Print a single line. If a hero must turn left, print "LEFT" (without the quotes); If he must go straight ahead, print "TOWARDS" (without the quotes); if he should turn right, print "RIGHT" (without the quotes). | [
"0 0\n0 1\n1 1\n",
"-1 -1\n-3 -3\n-4 -4\n",
"-4 -6\n-3 -7\n-2 -6\n"
] | [
"RIGHT\n",
"TOWARDS\n",
"LEFT\n"
] | The picture to the first sample:
The red color shows points A, B and C. The blue arrow shows the hero's direction. The green color shows the hero's trajectory.
The picture to the second sample: | [
{
"input": "0 0\n0 1\n1 1",
"output": "RIGHT"
},
{
"input": "-1 -1\n-3 -3\n-4 -4",
"output": "TOWARDS"
},
{
"input": "-4 -6\n-3 -7\n-2 -6",
"output": "LEFT"
},
{
"input": "-44 57\n-118 -41\n-216 33",
"output": "RIGHT"
},
{
"input": "39 100\n90 85\n105 136",
"o... | 124 | 6,963,200 | 3 | 1,323 | |
0 | none | [
"none"
] | null | null | On the way to school, Karen became fixated on the puzzle game on her phone!
The game is played as follows. In each level, you have a grid with *n* rows and *m* columns. Each cell originally contains the number 0.
One move consists of choosing one row or column, and adding 1 to all of the cells in that row or column.
To win the level, after all the moves, the number in the cell at the *i*-th row and *j*-th column should be equal to *g**i*,<=*j*.
Karen is stuck on one level, and wants to know a way to beat this level using the minimum number of moves. Please, help her with this task! | The first line of input contains two integers, *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=100), the number of rows and the number of columns in the grid, respectively.
The next *n* lines each contain *m* integers. In particular, the *j*-th integer in the *i*-th of these rows contains *g**i*,<=*j* (0<=≤<=*g**i*,<=*j*<=≤<=500). | If there is an error and it is actually not possible to beat the level, output a single integer -1.
Otherwise, on the first line, output a single integer *k*, the minimum number of moves necessary to beat the level.
The next *k* lines should each contain one of the following, describing the moves in the order they must be done:
- row *x*, (1<=≤<=*x*<=≤<=*n*) describing a move of the form "choose the *x*-th row". - col *x*, (1<=≤<=*x*<=≤<=*m*) describing a move of the form "choose the *x*-th column".
If there are multiple optimal solutions, output any one of them. | [
"3 5\n2 2 2 3 2\n0 0 0 1 0\n1 1 1 2 1\n",
"3 3\n0 0 0\n0 1 0\n0 0 0\n",
"3 3\n1 1 1\n1 1 1\n1 1 1\n"
] | [
"4\nrow 1\nrow 1\ncol 4\nrow 3\n",
"-1\n",
"3\nrow 1\nrow 2\nrow 3\n"
] | In the first test case, Karen has a grid with 3 rows and 5 columns. She can perform the following 4 moves to beat the level:
In the second test case, Karen has a grid with 3 rows and 3 columns. It is clear that it is impossible to beat the level; performing any move will create three 1s on the grid, but it is required to only have one 1 in the center.
In the third test case, Karen has a grid with 3 rows and 3 columns. She can perform the following 3 moves to beat the level:
Note that this is not the only solution; another solution, among others, is col 1, col 2, col 3. | [
{
"input": "3 5\n2 2 2 3 2\n0 0 0 1 0\n1 1 1 2 1",
"output": "4\nrow 1\nrow 1\ncol 4\nrow 3"
},
{
"input": "3 3\n0 0 0\n0 1 0\n0 0 0",
"output": "-1"
},
{
"input": "3 3\n1 1 1\n1 1 1\n1 1 1",
"output": "3\nrow 1\nrow 2\nrow 3"
},
{
"input": "3 5\n2 4 2 2 3\n0 2 0 0 1\n1 3 1 1... | 374 | 819,200 | 3 | 1,329 | |
340 | Tourist Problem | [
"combinatorics",
"implementation",
"math"
] | null | null | Iahub is a big fan of tourists. He wants to become a tourist himself, so he planned a trip. There are *n* destinations on a straight road that Iahub wants to visit. Iahub starts the excursion from kilometer 0. The *n* destinations are described by a non-negative integers sequence *a*1, *a*2, ..., *a**n*. The number *a**k* represents that the *k*th destination is at distance *a**k* kilometers from the starting point. No two destinations are located in the same place.
Iahub wants to visit each destination only once. Note that, crossing through a destination is not considered visiting, unless Iahub explicitly wants to visit it at that point. Also, after Iahub visits his last destination, he doesn't come back to kilometer 0, as he stops his trip at the last destination.
The distance between destination located at kilometer *x* and next destination, located at kilometer *y*, is |*x*<=-<=*y*| kilometers. We call a "route" an order of visiting the destinations. Iahub can visit destinations in any order he wants, as long as he visits all *n* destinations and he doesn't visit a destination more than once.
Iahub starts writing out on a paper all possible routes and for each of them, he notes the total distance he would walk. He's interested in the average number of kilometers he would walk by choosing a route. As he got bored of writing out all the routes, he asks you to help him. | The first line contains integer *n* (2<=≤<=*n*<=≤<=105). Next line contains *n* distinct integers *a*1, *a*2, ..., *a**n* (1<=≤<=*a**i*<=≤<=107). | Output two integers — the numerator and denominator of a fraction which is equal to the wanted average number. The fraction must be irreducible. | [
"3\n2 3 5\n"
] | [
"22 3"
] | Consider 6 possible routes:
- [2, 3, 5]: total distance traveled: |2 – 0| + |3 – 2| + |5 – 3| = 5; - [2, 5, 3]: |2 – 0| + |5 – 2| + |3 – 5| = 7; - [3, 2, 5]: |3 – 0| + |2 – 3| + |5 – 2| = 7; - [3, 5, 2]: |3 – 0| + |5 – 3| + |2 – 5| = 8; - [5, 2, 3]: |5 – 0| + |2 – 5| + |3 – 2| = 9; - [5, 3, 2]: |5 – 0| + |3 – 5| + |2 – 3| = 8.
The average travel distance is <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/29119d3733c79f70eb2d77186ac1606bf938508a.png" style="max-width: 100.0%;max-height: 100.0%;"/> = <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/ee9d5516ed2ca1d2b65ed21f8a64f58f94954c30.png" style="max-width: 100.0%;max-height: 100.0%;"/> = <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/ed5cc8cb7dd43cfb27f2459586062538e44de7bd.png" style="max-width: 100.0%;max-height: 100.0%;"/>. | [
{
"input": "3\n2 3 5",
"output": "22 3"
},
{
"input": "4\n1 5 77 2",
"output": "547 4"
},
{
"input": "5\n3 3842 288 199 334",
"output": "35918 5"
},
{
"input": "7\n1 2 3 40 52 33 86",
"output": "255 1"
},
{
"input": "7\n1 10 100 1000 10000 1000000 10000000",
"... | 528 | 7,577,600 | 3 | 1,337 | |
190 | Vasya and the Bus | [
"greedy",
"math"
] | null | null | One day Vasya heard a story: "In the city of High Bertown a bus number 62 left from the bus station. It had *n* grown-ups and *m* kids..."
The latter events happen to be of no importance to us. Vasya is an accountant and he loves counting money. So he wondered what maximum and minimum sum of money these passengers could have paid for the ride.
The bus fare equals one berland ruble in High Bertown. However, not everything is that easy — no more than one child can ride for free with each grown-up passenger. That means that a grown-up passenger who rides with his *k* (*k*<=><=0) children, pays overall *k* rubles: a ticket for himself and (*k*<=-<=1) tickets for his children. Also, a grown-up can ride without children, in this case he only pays one ruble.
We know that in High Bertown children can't ride in a bus unaccompanied by grown-ups.
Help Vasya count the minimum and the maximum sum in Berland rubles, that all passengers of this bus could have paid in total. | The input file consists of a single line containing two space-separated numbers *n* and *m* (0<=≤<=*n*,<=*m*<=≤<=105) — the number of the grown-ups and the number of the children in the bus, correspondingly. | If *n* grown-ups and *m* children could have ridden in the bus, then print on a single line two space-separated integers — the minimum and the maximum possible total bus fare, correspondingly.
Otherwise, print "Impossible" (without the quotes). | [
"1 2\n",
"0 5\n",
"2 2\n"
] | [
"2 2",
"Impossible",
"2 3"
] | In the first sample a grown-up rides with two children and pays two rubles.
In the second sample there are only children in the bus, so the situation is impossible.
In the third sample there are two cases: - Each of the two grown-ups rides with one children and pays one ruble for the tickets. In this case the passengers pay two rubles in total. - One of the grown-ups ride with two children's and pays two rubles, the another one rides alone and pays one ruble for himself. So, they pay three rubles in total. | [
{
"input": "1 2",
"output": "2 2"
},
{
"input": "0 5",
"output": "Impossible"
},
{
"input": "2 2",
"output": "2 3"
},
{
"input": "2 7",
"output": "7 8"
},
{
"input": "4 10",
"output": "10 13"
},
{
"input": "6 0",
"output": "6 6"
},
{
"input... | 92 | 0 | 0 | 1,338 | |
650 | Watchmen | [
"data structures",
"geometry",
"math"
] | null | null | Watchmen are in a danger and Doctor Manhattan together with his friend Daniel Dreiberg should warn them as soon as possible. There are *n* watchmen on a plane, the *i*-th watchman is located at point (*x**i*,<=*y**i*).
They need to arrange a plan, but there are some difficulties on their way. As you know, Doctor Manhattan considers the distance between watchmen *i* and *j* to be |*x**i*<=-<=*x**j*|<=+<=|*y**i*<=-<=*y**j*|. Daniel, as an ordinary person, calculates the distance using the formula .
The success of the operation relies on the number of pairs (*i*,<=*j*) (1<=≤<=*i*<=<<=*j*<=≤<=*n*), such that the distance between watchman *i* and watchmen *j* calculated by Doctor Manhattan is equal to the distance between them calculated by Daniel. You were asked to compute the number of such pairs. | The first line of the input contains the single integer *n* (1<=≤<=*n*<=≤<=200<=000) — the number of watchmen.
Each of the following *n* lines contains two integers *x**i* and *y**i* (|*x**i*|,<=|*y**i*|<=≤<=109).
Some positions may coincide. | Print the number of pairs of watchmen such that the distance between them calculated by Doctor Manhattan is equal to the distance calculated by Daniel. | [
"3\n1 1\n7 5\n1 5\n",
"6\n0 0\n0 1\n0 2\n-1 1\n0 1\n1 1\n"
] | [
"2\n",
"11\n"
] | In the first sample, the distance between watchman 1 and watchman 2 is equal to |1 - 7| + |1 - 5| = 10 for Doctor Manhattan and <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/bcb5b7064b5f02088da0fdcf677e6fda495dd0df.png" style="max-width: 100.0%;max-height: 100.0%;"/> for Daniel. For pairs (1, 1), (1, 5) and (7, 5), (1, 5) Doctor Manhattan and Daniel will calculate the same distances. | [
{
"input": "3\n1 1\n7 5\n1 5",
"output": "2"
},
{
"input": "6\n0 0\n0 1\n0 2\n-1 1\n0 1\n1 1",
"output": "11"
},
{
"input": "10\n46 -55\n46 45\n46 45\n83 -55\n46 45\n83 -55\n46 45\n83 45\n83 45\n46 -55",
"output": "33"
},
{
"input": "1\n-5 -90",
"output": "0"
},
{
... | 0 | 0 | -1 | 1,341 | |
625 | K-special Tables | [
"constructive algorithms",
"implementation"
] | null | null | People do many crazy things to stand out in a crowd. Some of them dance, some learn by heart rules of Russian language, some try to become an outstanding competitive programmers, while others collect funny math objects.
Alis is among these collectors. Right now she wants to get one of *k*-special tables. In case you forget, the table *n*<=×<=*n* is called *k*-special if the following three conditions are satisfied:
- every integer from 1 to *n*2 appears in the table exactly once; - in each row numbers are situated in increasing order; - the sum of numbers in the *k*-th column is maximum possible.
Your goal is to help Alice and find at least one *k*-special table of size *n*<=×<=*n*. Both rows and columns are numbered from 1 to *n*, with rows numbered from top to bottom and columns numbered from left to right. | The first line of the input contains two integers *n* and *k* (1<=≤<=*n*<=≤<=500,<=1<=≤<=*k*<=≤<=*n*) — the size of the table Alice is looking for and the column that should have maximum possible sum. | First print the sum of the integers in the *k*-th column of the required table.
Next *n* lines should contain the description of the table itself: first line should contains *n* elements of the first row, second line should contain *n* elements of the second row and so on.
If there are multiple suitable table, you are allowed to print any. | [
"4 1\n",
"5 3\n"
] | [
"28\n1 2 3 4\n5 6 7 8\n9 10 11 12\n13 14 15 16\n",
"85\n5 6 17 18 19\n9 10 23 24 25\n7 8 20 21 22\n3 4 14 15 16\n1 2 11 12 13\n\n"
] | none | [
{
"input": "4 1",
"output": "28\n1 2 3 4\n5 6 7 8\n9 10 11 12\n13 14 15 16"
},
{
"input": "5 3",
"output": "85\n1 2 11 12 13\n3 4 14 15 16\n5 6 17 18 19\n7 8 20 21 22\n9 10 23 24 25"
},
{
"input": "1 1",
"output": "1\n1"
},
{
"input": "2 1",
"output": "4\n1 2\n3 4"
},
... | 93 | 4,608,000 | 3 | 1,342 | |
1,006 | Adjacent Replacements | [
"implementation"
] | null | null | Mishka got an integer array $a$ of length $n$ as a birthday present (what a surprise!).
Mishka doesn't like this present and wants to change it somehow. He has invented an algorithm and called it "Mishka's Adjacent Replacements Algorithm". This algorithm can be represented as a sequence of steps:
- Replace each occurrence of $1$ in the array $a$ with $2$; - Replace each occurrence of $2$ in the array $a$ with $1$; - Replace each occurrence of $3$ in the array $a$ with $4$; - Replace each occurrence of $4$ in the array $a$ with $3$; - Replace each occurrence of $5$ in the array $a$ with $6$; - Replace each occurrence of $6$ in the array $a$ with $5$; - $\dots$ - Replace each occurrence of $10^9 - 1$ in the array $a$ with $10^9$; - Replace each occurrence of $10^9$ in the array $a$ with $10^9 - 1$.
Note that the dots in the middle of this algorithm mean that Mishka applies these replacements for each pair of adjacent integers ($2i - 1, 2i$) for each $i \in\{1, 2, \ldots, 5 \cdot 10^8\}$ as described above.
For example, for the array $a = [1, 2, 4, 5, 10]$, the following sequence of arrays represents the algorithm:
$[1, 2, 4, 5, 10]$ $\rightarrow$ (replace all occurrences of $1$ with $2$) $\rightarrow$ $[2, 2, 4, 5, 10]$ $\rightarrow$ (replace all occurrences of $2$ with $1$) $\rightarrow$ $[1, 1, 4, 5, 10]$ $\rightarrow$ (replace all occurrences of $3$ with $4$) $\rightarrow$ $[1, 1, 4, 5, 10]$ $\rightarrow$ (replace all occurrences of $4$ with $3$) $\rightarrow$ $[1, 1, 3, 5, 10]$ $\rightarrow$ (replace all occurrences of $5$ with $6$) $\rightarrow$ $[1, 1, 3, 6, 10]$ $\rightarrow$ (replace all occurrences of $6$ with $5$) $\rightarrow$ $[1, 1, 3, 5, 10]$ $\rightarrow$ $\dots$ $\rightarrow$ $[1, 1, 3, 5, 10]$ $\rightarrow$ (replace all occurrences of $10$ with $9$) $\rightarrow$ $[1, 1, 3, 5, 9]$. The later steps of the algorithm do not change the array.
Mishka is very lazy and he doesn't want to apply these changes by himself. But he is very interested in their result. Help him find it. | The first line of the input contains one integer number $n$ ($1 \le n \le 1000$) — the number of elements in Mishka's birthday present (surprisingly, an array).
The second line of the input contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^9$) — the elements of the array. | Print $n$ integers — $b_1, b_2, \dots, b_n$, where $b_i$ is the final value of the $i$-th element of the array after applying "Mishka's Adjacent Replacements Algorithm" to the array $a$. Note that you cannot change the order of elements in the array. | [
"5\n1 2 4 5 10\n",
"10\n10000 10 50605065 1 5 89 5 999999999 60506056 1000000000\n"
] | [
"1 1 3 5 9\n",
"9999 9 50605065 1 5 89 5 999999999 60506055 999999999\n"
] | The first example is described in the problem statement. | [
{
"input": "5\n1 2 4 5 10",
"output": "1 1 3 5 9"
},
{
"input": "10\n10000 10 50605065 1 5 89 5 999999999 60506056 1000000000",
"output": "9999 9 50605065 1 5 89 5 999999999 60506055 999999999"
},
{
"input": "1\n999999999",
"output": "999999999"
},
{
"input": "1\n1000000000",... | 93 | 6,963,200 | 3 | 1,343 | |
21 | Jabber ID | [
"implementation",
"strings"
] | A. Jabber ID | 0 | 256 | Jabber ID on the national Berland service «Babber» has a form <username>@<hostname>[/resource], where
- <username> — is a sequence of Latin letters (lowercase or uppercase), digits or underscores characters «_», the length of <username> is between 1 and 16, inclusive. - <hostname> — is a sequence of word separated by periods (characters «.»), where each word should contain only characters allowed for <username>, the length of each word is between 1 and 16, inclusive. The length of <hostname> is between 1 and 32, inclusive. - <resource> — is a sequence of Latin letters (lowercase or uppercase), digits or underscores characters «_», the length of <resource> is between 1 and 16, inclusive.
The content of square brackets is optional — it can be present or can be absent.
There are the samples of correct Jabber IDs: [[email protected]](/cdn-cgi/l/email-protection), [[email protected]](/cdn-cgi/l/email-protection)/contest.
Your task is to write program which checks if given string is a correct Jabber ID. | The input contains of a single line. The line has the length between 1 and 100 characters, inclusive. Each characters has ASCII-code between 33 and 127, inclusive. | Print YES or NO. | [
"[email protected]\n",
"[email protected]/contest.icpc/12\n"
] | [
"YES\n",
"NO\n"
] | none | [
{
"input": "mike@codeforces.com",
"output": "YES"
},
{
"input": "john.smith@codeforces.ru/contest.icpc/12",
"output": "NO"
},
{
"input": "test@test.ri/abacaba",
"output": "YES"
},
{
"input": "@ops",
"output": "NO"
},
{
"input": "this-is-the-test",
"output": "N... | 62 | 0 | 0 | 1,344 |
443 | Anton and Letters | [
"constructive algorithms",
"implementation"
] | null | null | Recently, Anton has found a set. The set consists of small English letters. Anton carefully wrote out all the letters from the set in one line, separated by a comma. He also added an opening curved bracket at the beginning of the line and a closing curved bracket at the end of the line.
Unfortunately, from time to time Anton would forget writing some letter and write it again. He asks you to count the total number of distinct letters in his set. | The first and the single line contains the set of letters. The length of the line doesn't exceed 1000. It is guaranteed that the line starts from an opening curved bracket and ends with a closing curved bracket. Between them, small English letters are listed, separated by a comma. Each comma is followed by a space. | Print a single number — the number of distinct letters in Anton's set. | [
"{a, b, c}\n",
"{b, a, b, a}\n",
"{}\n"
] | [
"3\n",
"2\n",
"0\n"
] | none | [
{
"input": "{a, b, c}",
"output": "3"
},
{
"input": "{b, a, b, a}",
"output": "2"
},
{
"input": "{}",
"output": "0"
},
{
"input": "{a, a, c, b, b, b, c, c, c, c}",
"output": "3"
},
{
"input": "{a, c, b, b}",
"output": "3"
},
{
"input": "{a, b}",
"o... | 93 | 0 | 3 | 1,346 | |
985 | Switches and Lamps | [
"implementation"
] | null | null | You are given *n* switches and *m* lamps. The *i*-th switch turns on some subset of the lamps. This information is given as the matrix *a* consisting of *n* rows and *m* columns where *a**i*,<=*j*<==<=1 if the *i*-th switch turns on the *j*-th lamp and *a**i*,<=*j*<==<=0 if the *i*-th switch is not connected to the *j*-th lamp.
Initially all *m* lamps are turned off.
Switches change state only from "off" to "on". It means that if you press two or more switches connected to the same lamp then the lamp will be turned on after any of this switches is pressed and will remain its state even if any switch connected to this lamp is pressed afterwards.
It is guaranteed that if you push all *n* switches then all *m* lamps will be turned on.
Your think that you have too many switches and you would like to ignore one of them.
Your task is to say if there exists such a switch that if you will ignore (not use) it but press all the other *n*<=-<=1 switches then all the *m* lamps will be turned on. | The first line of the input contains two integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=2000) — the number of the switches and the number of the lamps.
The following *n* lines contain *m* characters each. The character *a**i*,<=*j* is equal to '1' if the *i*-th switch turns on the *j*-th lamp and '0' otherwise.
It is guaranteed that if you press all *n* switches all *m* lamps will be turned on. | Print "YES" if there is a switch that if you will ignore it and press all the other *n*<=-<=1 switches then all *m* lamps will be turned on. Print "NO" if there is no such switch. | [
"4 5\n10101\n01000\n00111\n10000\n",
"4 5\n10100\n01000\n00110\n00101\n"
] | [
"YES\n",
"NO\n"
] | none | [
{
"input": "4 5\n10101\n01000\n00111\n10000",
"output": "YES"
},
{
"input": "4 5\n10100\n01000\n00110\n00101",
"output": "NO"
},
{
"input": "1 5\n11111",
"output": "NO"
},
{
"input": "10 1\n1\n0\n0\n0\n0\n0\n0\n0\n0\n1",
"output": "YES"
},
{
"input": "1 1\n1",
... | 2,355 | 4,710,400 | 0 | 1,347 | |
220 | Little Elephant and Array | [
"constructive algorithms",
"data structures"
] | null | null | The Little Elephant loves playing with arrays. He has array *a*, consisting of *n* positive integers, indexed from 1 to *n*. Let's denote the number with index *i* as *a**i*.
Additionally the Little Elephant has *m* queries to the array, each query is characterised by a pair of integers *l**j* and *r**j* (1<=≤<=*l**j*<=≤<=*r**j*<=≤<=*n*). For each query *l**j*,<=*r**j* the Little Elephant has to count, how many numbers *x* exist, such that number *x* occurs exactly *x* times among numbers *a**l**j*,<=*a**l**j*<=+<=1,<=...,<=*a**r**j*.
Help the Little Elephant to count the answers to all queries. | The first line contains two space-separated integers *n* and *m* (1<=≤<=*n*,<=*m*<=≤<=105) — the size of array *a* and the number of queries to it. The next line contains *n* space-separated positive integers *a*1, *a*2, ..., *a**n* (1<=≤<=*a**i*<=≤<=109). Next *m* lines contain descriptions of queries, one per line. The *j*-th of these lines contains the description of the *j*-th query as two space-separated integers *l**j* and *r**j* (1<=≤<=*l**j*<=≤<=*r**j*<=≤<=*n*). | In *m* lines print *m* integers — the answers to the queries. The *j*-th line should contain the answer to the *j*-th query. | [
"7 2\n3 1 2 2 3 3 7\n1 7\n3 4\n"
] | [
"3\n1\n"
] | none | [
{
"input": "7 2\n3 1 2 2 3 3 7\n1 7\n3 4",
"output": "3\n1"
},
{
"input": "6 6\n1 2 2 3 3 3\n1 2\n2 2\n1 3\n2 4\n4 6\n1 6",
"output": "1\n0\n2\n1\n1\n3"
},
{
"input": "1 2\n1\n1 1\n1 1",
"output": "1\n1"
},
{
"input": "1 1\n1000000000\n1 1",
"output": "0"
}
] | 46 | 204,800 | -1 | 1,348 | |
946 | Partition | [
"greedy"
] | null | null | You are given a sequence *a* consisting of *n* integers. You may partition this sequence into two sequences *b* and *c* in such a way that every element belongs exactly to one of these sequences.
Let *B* be the sum of elements belonging to *b*, and *C* be the sum of elements belonging to *c* (if some of these sequences is empty, then its sum is 0). What is the maximum possible value of *B*<=-<=*C*? | The first line contains one integer *n* (1<=≤<=*n*<=≤<=100) — the number of elements in *a*.
The second line contains *n* integers *a*1, *a*2, ..., *a**n* (<=-<=100<=≤<=*a**i*<=≤<=100) — the elements of sequence *a*. | Print the maximum possible value of *B*<=-<=*C*, where *B* is the sum of elements of sequence *b*, and *C* is the sum of elements of sequence *c*. | [
"3\n1 -2 0\n",
"6\n16 23 16 15 42 8\n"
] | [
"3\n",
"120\n"
] | In the first example we may choose *b* = {1, 0}, *c* = { - 2}. Then *B* = 1, *C* = - 2, *B* - *C* = 3.
In the second example we choose *b* = {16, 23, 16, 15, 42, 8}, *c* = {} (an empty sequence). Then *B* = 120, *C* = 0, *B* - *C* = 120. | [
{
"input": "3\n1 -2 0",
"output": "3"
},
{
"input": "6\n16 23 16 15 42 8",
"output": "120"
},
{
"input": "1\n-1",
"output": "1"
},
{
"input": "100\n-100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 -10... | 109 | 0 | 3 | 1,354 | |
975 | Valhalla Siege | [
"binary search"
] | null | null | Ivar the Boneless is a great leader. He is trying to capture Kattegat from Lagertha. The war has begun and wave after wave Ivar's warriors are falling in battle.
Ivar has $n$ warriors, he places them on a straight line in front of the main gate, in a way that the $i$-th warrior stands right after $(i-1)$-th warrior. The first warrior leads the attack.
Each attacker can take up to $a_i$ arrows before he falls to the ground, where $a_i$ is the $i$-th warrior's strength.
Lagertha orders her warriors to shoot $k_i$ arrows during the $i$-th minute, the arrows one by one hit the first still standing warrior. After all Ivar's warriors fall and all the currently flying arrows fly by, Thor smashes his hammer and all Ivar's warriors get their previous strengths back and stand up to fight again. In other words, if all warriors die in minute $t$, they will all be standing to fight at the end of minute $t$.
The battle will last for $q$ minutes, after each minute you should tell Ivar what is the number of his standing warriors. | The first line contains two integers $n$ and $q$ ($1 \le n, q \leq 200\,000$) — the number of warriors and the number of minutes in the battle.
The second line contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq 10^9$) that represent the warriors' strengths.
The third line contains $q$ integers $k_1, k_2, \ldots, k_q$ ($1 \leq k_i \leq 10^{14}$), the $i$-th of them represents Lagertha's order at the $i$-th minute: $k_i$ arrows will attack the warriors. | Output $q$ lines, the $i$-th of them is the number of standing warriors after the $i$-th minute. | [
"5 5\n1 2 1 2 1\n3 10 1 1 1\n",
"4 4\n1 2 3 4\n9 1 10 6\n"
] | [
"3\n5\n4\n4\n3\n",
"1\n4\n4\n1\n"
] | In the first example:
- after the 1-st minute, the 1-st and 2-nd warriors die. - after the 2-nd minute all warriors die (and all arrows left over are wasted), then they will be revived thus answer is 5 — all warriors are alive. - after the 3-rd minute, the 1-st warrior dies. - after the 4-th minute, the 2-nd warrior takes a hit and his strength decreases by 1. - after the 5-th minute, the 2-nd warrior dies. | [
{
"input": "5 5\n1 2 1 2 1\n3 10 1 1 1",
"output": "3\n5\n4\n4\n3"
},
{
"input": "4 4\n1 2 3 4\n9 1 10 6",
"output": "1\n4\n4\n1"
},
{
"input": "10 3\n1 1 1 1 1 1 1 1 1 1\n10 10 5",
"output": "10\n10\n5"
},
{
"input": "1 1\n56563128\n897699770",
"output": "1"
},
{
... | 2,000 | 17,203,200 | 0 | 1,355 | |
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 bringing them closer left or right alternatively (you should start with bringing left). Study the sample tests carefully to understand the output format better. | [
"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... | 60 | 0 | 0 | 1,356 |
842 | Ilya And The Tree | [
"dfs and similar",
"graphs",
"math",
"number theory",
"trees"
] | null | null | Ilya is very fond of graphs, especially trees. During his last trip to the forest Ilya found a very interesting tree rooted at vertex 1. There is an integer number written on each vertex of the tree; the number written on vertex *i* is equal to *a**i*.
Ilya believes that the beauty of the vertex *x* is the greatest common divisor of all numbers written on the vertices on the path from the root to *x*, including this vertex itself. In addition, Ilya can change the number in one arbitrary vertex to 0 or leave all vertices unchanged. Now for each vertex Ilya wants to know the maximum possible beauty it can have.
For each vertex the answer must be considered independently.
The beauty of the root equals to number written on it. | First line contains one integer number *n* — the number of vertices in tree (1<=≤<=*n*<=≤<=2·105).
Next line contains *n* integer numbers *a**i* (1<=≤<=*i*<=≤<=*n*, 1<=≤<=*a**i*<=≤<=2·105).
Each of next *n*<=-<=1 lines contains two integer numbers *x* and *y* (1<=≤<=*x*,<=*y*<=≤<=*n*, *x*<=≠<=*y*), which means that there is an edge (*x*,<=*y*) in the tree. | Output *n* numbers separated by spaces, where *i*-th number equals to maximum possible beauty of vertex *i*. | [
"2\n6 2\n1 2\n",
"3\n6 2 3\n1 2\n1 3\n",
"1\n10\n"
] | [
"6 6 \n",
"6 6 6 \n",
"10 \n"
] | none | [
{
"input": "2\n6 2\n1 2",
"output": "6 6 "
},
{
"input": "3\n6 2 3\n1 2\n1 3",
"output": "6 6 6 "
},
{
"input": "1\n10",
"output": "10 "
},
{
"input": "10\n2 3 4 5 6 7 8 9 10 11\n1 2\n2 3\n3 4\n4 5\n5 6\n6 7\n4 8\n8 9\n9 10",
"output": "2 3 2 1 1 1 1 1 1 1 "
},
{
... | 233 | 149,401,600 | 0 | 1,358 | |
278 | New Problem | [
"brute force",
"strings"
] | null | null | Coming up with a new problem isn't as easy as many people think. Sometimes it is hard enough to name it. We'll consider a title original if it doesn't occur as a substring in any titles of recent Codeforces problems.
You've got the titles of *n* last problems — the strings, consisting of lowercase English letters. Your task is to find the shortest original title for the new problem. If there are multiple such titles, choose the lexicographically minimum one. Note, that title of the problem can't be an empty string.
A substring *s*[*l*... *r*] (1<=≤<=*l*<=≤<=*r*<=≤<=|*s*|) of string *s*<==<=*s*1*s*2... *s*|*s*| (where |*s*| is the length of string *s*) is string *s**l**s**l*<=+<=1... *s**r*.
String *x*<==<=*x*1*x*2... *x**p* is lexicographically smaller than string *y*<==<=*y*1*y*2... *y**q*, if either *p*<=<<=*q* and *x*1<==<=*y*1,<=*x*2<==<=*y*2,<=... ,<=*x**p*<==<=*y**p*, or there exists such number *r* (*r*<=<<=*p*,<=*r*<=<<=*q*), that *x*1<==<=*y*1,<=*x*2<==<=*y*2,<=... ,<=*x**r*<==<=*y**r* and *x**r*<=+<=1<=<<=*y**r*<=+<=1. The string characters are compared by their ASCII codes. | The first line contains integer *n* (1<=≤<=*n*<=≤<=30) — the number of titles you've got to consider. Then follow *n* problem titles, one per line. Each title only consists of lowercase English letters (specifically, it doesn't contain any spaces) and has the length from 1 to 20, inclusive. | Print a string, consisting of lowercase English letters — the lexicographically minimum shortest original title. | [
"5\nthreehorses\ngoodsubstrings\nsecret\nprimematrix\nbeautifulyear\n",
"4\naa\nbdefghijklmn\nopqrstuvwxyz\nc\n"
] | [
"j\n",
"ab\n"
] | In the first sample the first 9 letters of the English alphabet (a, b, c, d, e, f, g, h, i) occur in the problem titles, so the answer is letter j.
In the second sample the titles contain 26 English letters, so the shortest original title cannot have length 1. Title aa occurs as a substring in the first title. | [
{
"input": "5\nthreehorses\ngoodsubstrings\nsecret\nprimematrix\nbeautifulyear",
"output": "j"
},
{
"input": "4\naa\nbdefghijklmn\nopqrstuvwxyz\nc",
"output": "ab"
},
{
"input": "1\na",
"output": "b"
},
{
"input": "1\nb",
"output": "a"
},
{
"input": "1\nz",
"o... | 248 | 0 | 3 | 1,361 | |
129 | Cookies | [
"implementation"
] | null | null | Olga came to visit the twins Anna and Maria and saw that they have many cookies. The cookies are distributed into bags. As there are many cookies, Olga decided that it's no big deal if she steals a bag. However, she doesn't want the sisters to quarrel because of nothing when they divide the cookies. That's why Olga wants to steal a bag with cookies so that the number of cookies in the remaining bags was even, that is, so that Anna and Maria could evenly divide it into two (even 0 remaining cookies will do, just as any other even number). How many ways there are to steal exactly one cookie bag so that the total number of cookies in the remaining bags was even? | The first line contains the only integer *n* (1<=≤<=*n*<=≤<=100) — the number of cookie bags Anna and Maria have. The second line contains *n* integers *a**i* (1<=≤<=*a**i*<=≤<=100) — the number of cookies in the *i*-th bag. | Print in the only line the only number — the sought number of ways. If there are no such ways print 0. | [
"1\n1\n",
"10\n1 2 2 3 4 4 4 2 2 2\n",
"11\n2 2 2 2 2 2 2 2 2 2 99\n"
] | [
"1\n",
"8\n",
"1\n"
] | In the first sample Olga should take the only bag so that the twins ended up with the even number of cookies.
In the second sample Olga can take any of five bags with two cookies or any of three bags with four cookies — 5 + 3 = 8 ways in total.
In the third sample, no matter which bag with two cookies Olga chooses, the twins are left with 2 * 9 + 99 = 117 cookies. Thus, Olga has only one option: to take the bag with 99 cookies. | [
{
"input": "1\n1",
"output": "1"
},
{
"input": "10\n1 2 2 3 4 4 4 2 2 2",
"output": "8"
},
{
"input": "11\n2 2 2 2 2 2 2 2 2 2 99",
"output": "1"
},
{
"input": "2\n1 1",
"output": "0"
},
{
"input": "2\n2 2",
"output": "2"
},
{
"input": "2\n1 2",
"o... | 92 | 4,505,600 | 3 | 1,364 | |
988 | Diverse Team | [
"brute force",
"implementation"
] | null | null | There are $n$ students in a school class, the rating of the $i$-th student on Codehorses is $a_i$. You have to form a team consisting of $k$ students ($1 \le k \le n$) such that the ratings of all team members are distinct.
If it is impossible to form a suitable team, print "NO" (without quotes). Otherwise print "YES", and then print $k$ distinct numbers which should be the indices of students in the team you form. If there are multiple answers, print any of them. | The first line contains two integers $n$ and $k$ ($1 \le k \le n \le 100$) — the number of students and the size of the team you have to form.
The second line contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 100$), where $a_i$ is the rating of $i$-th student. | If it is impossible to form a suitable team, print "NO" (without quotes). Otherwise print "YES", and then print $k$ distinct integers from $1$ to $n$ which should be the indices of students in the team you form. All the ratings of the students in the team should be distinct. You may print the indices in any order. If there are multiple answers, print any of them.
Assume that the students are numbered from $1$ to $n$. | [
"5 3\n15 13 15 15 12\n",
"5 4\n15 13 15 15 12\n",
"4 4\n20 10 40 30\n"
] | [
"YES\n1 2 5 \n",
"NO\n",
"YES\n1 2 3 4 \n"
] | All possible answers for the first example:
- {1 2 5} - {2 3 5} - {2 4 5}
Note that the order does not matter. | [
{
"input": "5 3\n15 13 15 15 12",
"output": "YES\n1 2 5 "
},
{
"input": "5 4\n15 13 15 15 12",
"output": "NO"
},
{
"input": "4 4\n20 10 40 30",
"output": "YES\n1 2 3 4 "
},
{
"input": "1 1\n1",
"output": "YES\n1 "
},
{
"input": "100 53\n16 17 1 2 27 5 9 9 53 24 17... | 62 | 0 | 3 | 1,366 | |
246 | Buggy Sorting | [
"constructive algorithms",
"greedy",
"sortings"
] | null | null | Little boy Valera studies an algorithm of sorting an integer array. After studying the theory, he went on to the practical tasks. As a result, he wrote a program that sorts an array of *n* integers *a*1,<=*a*2,<=...,<=*a**n* in the non-decreasing order. The pseudocode of the program, written by Valera, is given below. The input of the program gets number *n* and array *a*.
But Valera could have made a mistake, because he hasn't yet fully learned the sorting algorithm. If Valera made a mistake in his program, you need to give a counter-example that makes his program work improperly (that is, the example that makes the program sort the array not in the non-decreasing order). If such example for the given value of *n* doesn't exist, print -1. | You've got a single integer *n* (1<=≤<=*n*<=≤<=50) — the size of the sorted array. | Print *n* space-separated integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=100) — the counter-example, for which Valera's algorithm won't work correctly. If the counter-example that meets the described conditions is impossible to give, print -1.
If there are several counter-examples, consisting of *n* numbers, you are allowed to print any of them. | [
"1\n"
] | [
"-1\n"
] | none | [
{
"input": "1",
"output": "-1"
},
{
"input": "2",
"output": "-1"
},
{
"input": "3",
"output": "3 2 1 "
},
{
"input": "4",
"output": "4 3 2 1 "
},
{
"input": "5",
"output": "5 4 3 2 1 "
},
{
"input": "6",
"output": "6 5 4 3 2 1 "
},
{
"input... | 46 | 0 | 3 | 1,367 | |
544 | Sea and Islands | [
"constructive algorithms",
"implementation"
] | null | null | A map of some object is a rectangular field consisting of *n* rows and *n* columns. Each cell is initially occupied by the sea but you can cover some some cells of the map with sand so that exactly *k* islands appear on the map. We will call a set of sand cells to be island if it is possible to get from each of them to each of them by moving only through sand cells and by moving from a cell only to a side-adjacent cell. The cells are called to be side-adjacent if they share a vertical or horizontal side. It is easy to see that islands do not share cells (otherwise they together form a bigger island).
Find a way to cover some cells with sand so that exactly *k* islands appear on the *n*<=×<=*n* map, or determine that no such way exists. | The single line contains two positive integers *n*, *k* (1<=≤<=*n*<=≤<=100, 0<=≤<=*k*<=≤<=*n*2) — the size of the map and the number of islands you should form. | If the answer doesn't exist, print "NO" (without the quotes) in a single line.
Otherwise, print "YES" in the first line. In the next *n* lines print the description of the map. Each of the lines of the description must consist only of characters 'S' and 'L', where 'S' is a cell that is occupied by the sea and 'L' is the cell covered with sand. The length of each line of the description must equal *n*.
If there are multiple answers, you may print any of them.
You should not maximize the sizes of islands. | [
"5 2\n",
"5 25\n"
] | [
"YES\nSSSSS\nLLLLL\nSSSSS\nLLLLL\nSSSSS\n",
"NO\n"
] | none | [
{
"input": "5 2",
"output": "YES\nSSSSS\nLLLLL\nSSSSS\nLLLLL\nSSSSS"
},
{
"input": "5 25",
"output": "NO"
},
{
"input": "82 6047",
"output": "NO"
},
{
"input": "6 5",
"output": "YES\nLSLSLS\nSLSLSS\nSSSSSS\nSSSSSS\nSSSSSS\nSSSSSS"
},
{
"input": "10 80",
"outpu... | 124 | 307,200 | 3 | 1,368 | |
690 | Tree of Life (easy) | [] | null | null | Heidi has finally found the mythical Tree of Life – a legendary combinatorial structure which is said to contain a prophecy crucially needed to defeat the undead armies.
On the surface, the Tree of Life is just a regular undirected tree well-known from computer science. This means that it is a collection of *n* points (called vertices), some of which are connected using *n*<=-<=1 line segments (edges) so that each pair of vertices is connected by a path (a sequence of one or more edges).
To decipher the prophecy, Heidi needs to perform a number of steps. The first is counting the number of lifelines in the tree – these are paths of length 2, i.e., consisting of two edges. Help her! | The first line of the input contains a single integer *n* – the number of vertices in the tree (1<=≤<=*n*<=≤<=10000). The vertices are labeled with the numbers from 1 to *n*. Then *n*<=-<=1 lines follow, each describing one edge using two space-separated numbers *a* *b* – the labels of the vertices connected by the edge (1<=≤<=*a*<=<<=*b*<=≤<=*n*). It is guaranteed that the input represents a tree. | Print one integer – the number of lifelines in the tree. | [
"4\n1 2\n1 3\n1 4\n",
"5\n1 2\n2 3\n3 4\n3 5\n"
] | [
"3",
"4"
] | In the second sample, there are four lifelines: paths between vertices 1 and 3, 2 and 4, 2 and 5, and 4 and 5. | [
{
"input": "4\n1 2\n1 3\n1 4",
"output": "3"
},
{
"input": "5\n1 2\n2 3\n3 4\n3 5",
"output": "4"
},
{
"input": "2\n1 2",
"output": "0"
},
{
"input": "3\n2 1\n3 2",
"output": "1"
},
{
"input": "10\n5 1\n1 2\n9 3\n10 5\n6 3\n8 5\n2 7\n2 3\n9 4",
"output": "11"
... | 93 | 4,812,800 | 3 | 1,369 | |
793 | Oleg and shares | [
"implementation",
"math"
] | null | null | Oleg the bank client checks share prices every day. There are *n* share prices he is interested in. Today he observed that each second exactly one of these prices decreases by *k* rubles (note that each second exactly one price changes, but at different seconds different prices can change). Prices can become negative. Oleg found this process interesting, and he asked Igor the financial analyst, what is the minimum time needed for all *n* prices to become equal, or it is impossible at all? Igor is busy right now, so he asked you to help Oleg. Can you answer this question? | The first line contains two integers *n* and *k* (1<=≤<=*n*<=≤<=105,<=1<=≤<=*k*<=≤<=109) — the number of share prices, and the amount of rubles some price decreases each second.
The second line contains *n* integers *a*1,<=*a*2,<=...,<=*a**n* (1<=≤<=*a**i*<=≤<=109) — the initial prices. | Print the only line containing the minimum number of seconds needed for prices to become equal, of «-1» if it is impossible. | [
"3 3\n12 9 15\n",
"2 2\n10 9\n",
"4 1\n1 1000000000 1000000000 1000000000\n"
] | [
"3",
"-1",
"2999999997"
] | Consider the first example.
Suppose the third price decreases in the first second and become equal 12 rubles, then the first price decreases and becomes equal 9 rubles, and in the third second the third price decreases again and becomes equal 9 rubles. In this case all prices become equal 9 rubles in 3 seconds.
There could be other possibilities, but this minimizes the time needed for all prices to become equal. Thus the answer is 3.
In the second example we can notice that parity of first and second price is different and never changes within described process. Thus prices never can become equal.
In the third example following scenario can take place: firstly, the second price drops, then the third price, and then fourth price. It happens 999999999 times, and, since in one second only one price can drop, the whole process takes 999999999 * 3 = 2999999997 seconds. We can note that this is the minimum possible time. | [
{
"input": "3 3\n12 9 15",
"output": "3"
},
{
"input": "2 2\n10 9",
"output": "-1"
},
{
"input": "4 1\n1 1000000000 1000000000 1000000000",
"output": "2999999997"
},
{
"input": "1 11\n123",
"output": "0"
},
{
"input": "20 6\n38 86 86 50 98 62 32 2 14 62 98 50 2 50... | 202 | 10,956,800 | 3 | 1,372 | |
218 | Mountain Scenery | [
"brute force",
"constructive algorithms",
"implementation"
] | null | null | Little Bolek has found a picture with *n* mountain peaks painted on it. The *n* painted peaks are represented by a non-closed polyline, consisting of 2*n* segments. The segments go through 2*n*<=+<=1 points with coordinates (1,<=*y*1), (2,<=*y*2), ..., (2*n*<=+<=1,<=*y*2*n*<=+<=1), with the *i*-th segment connecting the point (*i*,<=*y**i*) and the point (*i*<=+<=1,<=*y**i*<=+<=1). For any even *i* (2<=≤<=*i*<=≤<=2*n*) the following condition holds: *y**i*<=-<=1<=<<=*y**i* and *y**i*<=><=*y**i*<=+<=1.
We shall call a vertex of a polyline with an even *x* coordinate a mountain peak.
Bolek fancied a little mischief. He chose exactly *k* mountain peaks, rubbed out the segments that went through those peaks and increased each peak's height by one (that is, he increased the *y* coordinate of the corresponding points). Then he painted the missing segments to get a new picture of mountain peaks. Let us denote the points through which the new polyline passes on Bolek's new picture as (1,<=*r*1), (2,<=*r*2), ..., (2*n*<=+<=1,<=*r*2*n*<=+<=1).
Given Bolek's final picture, restore the initial one. | The first line contains two space-separated integers *n* and *k* (1<=≤<=*k*<=≤<=*n*<=≤<=100). The next line contains 2*n*<=+<=1 space-separated integers *r*1,<=*r*2,<=...,<=*r*2*n*<=+<=1 (0<=≤<=*r**i*<=≤<=100) — the *y* coordinates of the polyline vertices on Bolek's picture.
It is guaranteed that we can obtain the given picture after performing the described actions on some picture of mountain peaks. | Print 2*n*<=+<=1 integers *y*1,<=*y*2,<=...,<=*y*2*n*<=+<=1 — the *y* coordinates of the vertices of the polyline on the initial picture. If there are multiple answers, output any one of them. | [
"3 2\n0 5 3 5 1 5 2\n",
"1 1\n0 2 0\n"
] | [
"0 5 3 4 1 4 2 \n",
"0 1 0 \n"
] | none | [
{
"input": "3 2\n0 5 3 5 1 5 2",
"output": "0 5 3 4 1 4 2 "
},
{
"input": "1 1\n0 2 0",
"output": "0 1 0 "
},
{
"input": "1 1\n1 100 0",
"output": "1 99 0 "
},
{
"input": "3 1\n0 1 0 1 0 2 0",
"output": "0 1 0 1 0 1 0 "
},
{
"input": "3 1\n0 1 0 2 0 1 0",
"out... | 216 | 0 | 0 | 1,374 | |
552 | Vanya and Table | [
"implementation",
"math"
] | null | null | Vanya has a table consisting of 100 rows, each row contains 100 cells. The rows are numbered by integers from 1 to 100 from bottom to top, the columns are numbered from 1 to 100 from left to right.
In this table, Vanya chose *n* rectangles with sides that go along borders of squares (some rectangles probably occur multiple times). After that for each cell of the table he counted the number of rectangles it belongs to and wrote this number into it. Now he wants to find the sum of values in all cells of the table and as the table is too large, he asks you to help him find the result. | The first line contains integer *n* (1<=≤<=*n*<=≤<=100) — the number of rectangles.
Each of the following *n* lines contains four integers *x*1,<=*y*1,<=*x*2,<=*y*2 (1<=≤<=*x*1<=≤<=*x*2<=≤<=100, 1<=≤<=*y*1<=≤<=*y*2<=≤<=100), where *x*1 and *y*1 are the number of the column and row of the lower left cell and *x*2 and *y*2 are the number of the column and row of the upper right cell of a rectangle. | In a single line print the sum of all values in the cells of the table. | [
"2\n1 1 2 3\n2 2 3 3\n",
"2\n1 1 3 3\n1 1 3 3\n"
] | [
"10\n",
"18\n"
] | Note to the first sample test:
Values of the table in the first three rows and columns will be as follows:
121
121
110
So, the sum of values will be equal to 10.
Note to the second sample test:
Values of the table in the first three rows and columns will be as follows:
222
222
222
So, the sum of values will be equal to 18. | [
{
"input": "2\n1 1 2 3\n2 2 3 3",
"output": "10"
},
{
"input": "2\n1 1 3 3\n1 1 3 3",
"output": "18"
},
{
"input": "5\n4 11 20 15\n7 5 12 20\n10 8 16 12\n7 5 12 15\n2 2 20 13",
"output": "510"
},
{
"input": "5\n4 11 20 20\n6 11 20 16\n5 2 19 15\n11 3 18 15\n3 2 14 11",
"o... | 77 | 0 | 3 | 1,376 | |
332 | Down the Hatch! | [
"implementation"
] | null | null | Everybody knows that the Berland citizens are keen on health, especially students. Berland students are so tough that all they drink is orange juice!
Yesterday one student, Vasya and his mates made some barbecue and they drank this healthy drink only. After they ran out of the first barrel of juice, they decided to play a simple game. All *n* people who came to the barbecue sat in a circle (thus each person received a unique index *b**i* from 0 to *n*<=-<=1). The person number 0 started the game (this time it was Vasya). All turns in the game were numbered by integers starting from 1. If the *j*-th turn was made by the person with index *b**i*, then this person acted like that:
1. he pointed at the person with index (*b**i*<=+<=1) *mod* *n* either with an elbow or with a nod (*x* *mod* *y* is the remainder after dividing *x* by *y*); 1. if *j*<=≥<=4 and the players who had turns number *j*<=-<=1, *j*<=-<=2, *j*<=-<=3, made during their turns the same moves as player *b**i* on the current turn, then he had drunk a glass of juice; 1. the turn went to person number (*b**i*<=+<=1) *mod* *n*.
The person who was pointed on the last turn did not make any actions.
The problem was, Vasya's drunk too much juice and can't remember the goal of the game. However, Vasya's got the recorded sequence of all the participants' actions (including himself). Now Vasya wants to find out the maximum amount of juice he could drink if he played optimally well (the other players' actions do not change). Help him.
You can assume that in any scenario, there is enough juice for everybody. | The first line contains a single integer *n* (4<=≤<=*n*<=≤<=2000) — the number of participants in the game. The second line describes the actual game: the *i*-th character of this line equals 'a', if the participant who moved *i*-th pointed at the next person with his elbow, and 'b', if the participant pointed with a nod. The game continued for at least 1 and at most 2000 turns. | Print a single integer — the number of glasses of juice Vasya could have drunk if he had played optimally well. | [
"4\nabbba\n",
"4\nabbab\n"
] | [
"1\n",
"0\n"
] | In both samples Vasya has got two turns — 1 and 5. In the first sample, Vasya could have drunk a glass of juice during the fifth turn if he had pointed at the next person with a nod. In this case, the sequence of moves would look like "abbbb". In the second sample Vasya wouldn't drink a single glass of juice as the moves performed during turns 3 and 4 are different. | [
{
"input": "4\nabbba",
"output": "1"
},
{
"input": "4\nabbab",
"output": "0"
},
{
"input": "4\naaa",
"output": "0"
},
{
"input": "4\naab",
"output": "0"
},
{
"input": "4\naabaabbba",
"output": "1"
},
{
"input": "6\naaaaaaaaaaaaaaaa",
"output": "2"
... | 60 | 0 | 0 | 1,386 |
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