c program to print 1 in diagonal positions of a matrix

Explanation of the program

This program reads a matrix and replaces the value stored in the diagonal positions with 1. The program uses two for loops, with loop variables i and j. The diagonal positions has the same value for i and j. If i and j equals, a 1 is stored at the position a[i][j].

Program

#include<stdio.h>

#include<conio.h>

void main()

{

clrscr();

int a[50][50]={0},i,j,r,c;

printf("Enter the row and column value:\n\n");

scanf("%d%d",&r,&c);

printf("\nEnter the elements:\n\n");

for(i=0;i<r;i++)

{

for(j=0;j<c;j++)

{

scanf("%d",&a[i][j]);

}}

for(i=0;i<r;i++)

{

for(j=0;j<c;j++)

{

if(i==j)

{

a[i][j]=1;

}}}

printf("\nNew matrix:\n");

for(i=0;i<r;i++)

{

printf("\n");

for(j=0;j<c;j++)

{

printf("%d\t",a[i][j]);

}}

getch();

}

Output

C program to change diagonal elements of a matrix to 1