Question

Given

int B[4][4]={...};

Write a code segment that exchange the values about the main diagonal of the matrix.

Answer 1

//C program


#include <stdio.h>

int main()
{   
    //variable initialization
    int B[4][4],i,j,m,n;
    int row, col, temp;
    //enter user input values to matrix B
    printf("\nEnter values to the matrix :: \n");
       for (i = 0; i < 4; i++)
        {
            for (j = 0; j < 4; j++)
            {
                 printf("\nEnter a[%d][%d] value :: ",i,j);
                 scanf("%d", &B[i][j]);
        }
    }
    //for loop show original matrix
    printf("\nThe given matrix is :: \n\n");

        for (i = 0; i < 4; ++i)
        {
            for (j = 0; j < 4; ++j)
            {
                printf("\t%d", B[i][j]);
            }
            printf("\n\n");
        }
    //Interchanges diagonal of the matrix
     
    for(row=0; row < 4; row++)
    {
        col = row;

        temp = B[row][col];
        B[row][col] = B[row][(4 - col)-1];
        B[row][(4 - col)-1] = temp;
    }

    // Prints the interchanged diagonals matrix
    printf("\nMatrix after diagonals interchanged: \n");
    for (i = 0; i < 4; ++i)
        {
            for (j = 0; j < 4; ++j)
            {
                printf("\t%d", B[i][j]);
            }
            printf("\n\n");
        }

    return 0;
}

Output::

Note:: If you have any queries regarding this please comment.