Basic practice alphabet graphics

Problem Description

There are some beautiful shapes that can be formed using letters, an example is given below:

ABCDEFG

BABCDEF

CBABCDE

DCBABCD

EDCBABC

This is a graph with 5 rows and 7 columns. Please find out the pattern of this graph and output a graph with n rows and m columns.

input format

Input a line, containing two integers n and m, which respectively represent the number of rows and columns of the graph you want to output.

output format

Output n lines, m characters each, for your graph.

sample input

5 7

Sample output

ABCDEFG
BABCDEF
CBABCDE
DCBABCD
EDCBABC

Data size and convention

1 <= n, m <= 26。

#include <stdio.h>
#include<math.h>
#include<limits.h>

char a[26] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
intmain()
{
    int m, n, i, j;

    scanf("%d%d", &m, &n);

    for(i=0; i<m; i++){

        for(j=0; j<n-1; j++)
        {
                printf("%c", a[abs(i-j)]);

        }
        printf("%c\n", a[abs(j-i)]);

    }
    return 0;
}

Only 70 points were submitted at the beginning,,, I forgot to consider the case that i is larger than j,,, o(￣ヘ￣o#) I looked at the test data and tested it before I saw it, I used abs,, be careful, ,,