Description

printf() and  scanf() format

printf("%d", n);
 

FORMAT  ARGUMENT TYPE

%d, %i  int           decimal

%u      unsigned int

%x      unsigned int  hexadecimal

%#x     unsigned int  hexadecimal with prefix 0x

%f      double  

%Lf     long double

%c      char         to print a character

%s      char *      string (character array ended with '\0')

scanf("%d", &n);
 

FORMAT  ARGUMENT TYPE

%d      int *       &n, store the input integer in n

%ld     long *

%lld    long long *

%u      unsigned int *

%f      float *     read float

%lf     double *    read double

%Lf     long double *   read long double

%c      char *      read 3 characters %3c

%s      char *      read a string until whitespace

%n      int *       with %s, to get string length

                   char a[100]; int len; 
                 scanf("%s%n", a, &len);
                 len will have the string length

Frequently used functions

To create a 5-by-5 two-dimensional array, we need to write

int a[5][5];

 

It will be indexed as follows:

 

a[0][0]	a[0][1]	a[0][2]	a[0][3]	a[0][4]
a[1][0]	a[1][1]	a[1][2]	a[1][3]	a[1][4]
a[2][0]	a[2][1]	a[2][2]	a[2][3]	a[2][4]
a[3][0]	a[3][1]	a[3][2]	a[3][3]	a[3][4]
a[4][0]	a[4][1]	a[4][2]	a[4][3]	a[4][4]

 

 

How to read the following data?
1 2 3 4 5 e
#include <stdio.h>
int main(void)
{
    int x;
    while (scanf("%d", &x) == 1) {  
     printf("x=%d\n", x);
    }
    return 0;
}

How to read the following data?

2

L 5 2
D 5 3

#include <stdio.h>

int main(void)

{

   char ch;
   int i, n, row, col;

   scanf("%d", &n);

   for (i=0; i<n; i++) {

      while(getchar()!='\n');

      scanf("%c%d%d", &ch, &row, &col);

   }

   return 0;

}

Using for loops to print a two-dimensional array

   for(i = 0; i < row; i++) {
      for (j = 0; j < col; j++) {
         printf("%5d", A[i][j]);
      }
      printf("\n");
   } 

How to avoid common errors and how to debug for OJ

1. Put the arrays in the 'global' area. Set their size bigger than required. Avoid using variable-length arrays (e.g. int arr[n];). Keep the array size fix (e.g., int arr[1000];).

2. After writing the code for reading input data, you may print out the data to check if your code reads them correctly. Do not proceed to write subsequent code before you confirm that.

3. If your program crashes, usually it is caused by memory related errors. Check the ranges of for-loops to see if your code attempts to read or write the elements out of the arrays' boundary.

 

Input

Output

Sample Input  Download

Sample Output  Download

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Description

In this problem, you are asked to implement a program which can find the maximum element M and minimum element m of a two-dimensional array. You need to print the location difference and value difference of M and m. For example, if M is at iM-th row and jM-th column and of value rM, and m is at im-th row and jm-th column and of value rm, then the location difference and value difference of the two elements are (|iM - im| + |jM - jm|) and (|rM - rm|), respectively.

Note that in a given array, no two elements will have the same value.

 

HINT: You can use C library function:  int abs(int x) ,which returns the absolute value of int x.

Before using abs(), you may need to add the following code at first : #include <stdlib.h>

Input

The first line of the input contains two integer numbers R (2<=R<=10) and C (2<=C<=10).

Each of the next R lines contains C integers, specifying the elements of the two-dimensional array. All of the integers in the same line are separated by a space.

Output

The output contains two integers:  the location difference and the value difference of the maximum and minimum elements, separated by a space.

Note that you do not need to print ‘\n’ at the end of line.

Sample Input  Download

Sample Output  Download

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Description

The Game of Life is devised by the British mathematician John Horton Conway.
This Game consists of a grid of cells, each of which is in one of possible state, live or dead.
For each generation, every cell interacts with its eight neighbors in the following rules:

1. Any live cell with two or three live neighbours survives.
2. Any dead cell with exactly three live neighbours becomes a live cell.
3. All other live cells die in the next generation. Similarly, all other dead cells stay dead.

 

The following 2 gifs are the examples of the Game of Life: ( Black = live, White = dead )

         
Given the initial state of n×m grid of cells.
Your task is to find the state of grid of cells after T generations.

Hint:
It's possible to access the invalid index ( arr[-1][0] ) of array when counting the neighbors.
In C, this behavior may not cause any error message.
Notice the boundary cases, and you will get AC in this problem. :)

Input

Three integers n, m, T on the first line.
The following n lines consist m numbers for each lines.
There’re si1, si2, ..., sim on the i^th line, representing the initial state of grid of cells.
sij denotes the state of cell at position (i,j), 0,1 mean dead and live respectively.

It’s guaranteed that:

• 1 ≤ n, m, T ≤ 500
• sij ∈ { 0, 1 }

Output

Print the grid of cells after T generations.
Remember ‘\n’ after the end of each line.

Sample Input  Download

Sample Output  Download

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Description

Megumin, a talent explosion magic archwizard, spends a lot of time studying explosion magic spells. For two magic spells A and B, she found that she can combine them together to create a powerful magic spell. Moreover, if the last k characters of A matches the first k characters of B, they can be merged to obtain a more powerful spell. Refer to homework for more examples.

Soon Megumin finds magic spell A too long and wants to shorten it to some substring A'. A substring is a contiguous sequence of characters within a string, specified with two indexes. For example, let A="yyyabcabdab", some substrings of A may be:

• A[3...10]="abcabdab" (start from index 3 , end with index 10)

• A[0...2]="yyy" (start from index 0 , end with index 2)

Given substring A' please tell her how many ways there are to merge A' with B.

Implementation Hints

1. Use strlen() to retrieve length of a string with caution. Remember to #include <string.h>

2. Estimating running time: recall that:

   How to estimate the running time of your code?

   A usual computer can run 10⁹ basic operations (such as +, -, &, |) in 1 second. Although this depends on the judging server, this number serves as a good estimation for the running time of your code. Try to figure out how much operations your code needs to execute to finish all the computations (since not all operations in your code are basic operations, another estimate criterion is 10⁸ operations (+, -, *, /, =, ...) in 1 second)!

3. (Maybe useless hint) Draw some examples on paper; observe them; think carefully what you can store to speed up your program.

Notes on Sample IO

Given A="yyyabcabdab", B="abcabd"

For the first substring A'=A[3…10]="abcabdab", possible ways of merging:

A' = abcabdab, B = abcabd
1)   ........abcabd
2)   ......abcabd

Therefore output 2

For the second substring A'=A[2…8]="yabcabd", possible ways of merging:

A' = yabcabd, B = abcabd
1)   .......abcabd
2)   .abcabd

Therefore output 2

For the third substring A'= A[2…7]="yabcab", possible ways of merging:

A' = yabcab, B = abcabd
1)   .......abcabd
2)   ....abcabd
3)   .abcabd

Therefore output 3

Input

The first line is an integer T, meaning that the input has T test data. Each test data contains multiple lines.

The first line of each data are two magic spells A and B, where they only contain lower case alphabets (a-z). The second line is an integer Q. In the following Q lines, each contains a substring A' specified with two integers L and R -- the start index and end index of substring of A.

For all test cases:

• 1 <= T <= 10

• 0 <= L <= R < |A|

For test case 1-3:

• 1 <= Q, |A|, |B| <= 100

For test case 4-5:

• 1 <= Q, |A|, |B| <= 2000

For test case 6:

• 1 <= Q <= 10⁶

• 1 <= |A|, |B| <= 2000

Output

For each substring A', output number of ways to merge A' with B in a single line. Remember to add '\n' in the end.

Sample Input  Download

Sample Output  Download

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