C Exercises: Multiplication of two Matrices

C Array: Exercise-21 with Solution

Write a program in C for the multiplication of two square matrices.

The task is to write a C program that performs multiplication of two square matrices. The program prompts the user to input the dimensions and elements for two matrices of the same size, computes their product, and displays the original matrices along with their multiplication result.

Visual Presentation:

Sample Solution:

C Code:

#include <stdio.h>

int main() {
    // Declare matrices and variables
    int arr1[50][50], brr1[50][50], crr1[50][50], i, j, k, r1, c1, r2, c2, sum = 0;

    // Display multiplication of two matrices
    printf("\n\nMultiplication of two Matrices :\n");
    printf("----------------------------------\n");

    // Input rows and columns of the first matrix
    printf("\nInput the rows and columns of the first matrix: ");
    scanf("%d %d", &r1, &c1);

    // Input rows and columns of the second matrix
    printf("\nInput the rows and columns of the second matrix: ");
    scanf("%d %d", &r2, &c2);

    // Check if multiplication is possible
    if (c1 != r2) {
        printf("Multiplication of matrices is not possible.\n");
        printf("Column of the first matrix and row of the second matrix must be the same.\n");
    } else {
        // Input elements in the first matrix
        printf("Input elements in the first matrix:\n");
        for (i = 0; i < r1; i++) {
            for (j = 0; j < c1; j++) {
                printf("element - [%d],[%d] : ", i, j);
                scanf("%d", &arr1[i][j]);
            }
        }

        // Input elements in the second matrix
        printf("Input elements in the second matrix:\n");
        for (i = 0; i < r2; i++) {
            for (j = 0; j < c2; j++) {
                printf("element - [%d],[%d] : ", i, j);
                scanf("%d", &brr1[i][j]);
            }
        }

        // Display the first matrix
        printf("\nThe First matrix is:\n");
        for (i = 0; i < r1; i++) {
            printf("\n");
            for (j = 0; j < c1; j++)
                printf("%d\t", arr1[i][j]);
        }

        // Display the second matrix
        printf("\nThe Second matrix is:\n");
        for (i = 0; i < r2; i++) {
            printf("\n");
            for (j = 0; j < c2; j++)
                printf("%d\t", brr1[i][j]);
        }

        // Matrix multiplication
        for (i = 0; i < r1; i++) { // Row of first matrix
            for (j = 0; j < c2; j++) { // Column of second matrix
                sum = 0;
                for (k = 0; k < c1; k++)
                    sum = sum + arr1[i][k] * brr1[k][j];
                crr1[i][j] = sum;
            }
        }

        // Display the result of matrix multiplication
        printf("\nThe multiplication of two matrices is:\n");
        for (i = 0; i < r1; i++) {
            printf("\n");
            for (j = 0; j < c2; j++)
                printf("%d\t", crr1[i][j]);
        }
    }
    printf("\n\n");
    return 0;
}

Sample Output:

Multiplication of two Matrices :                                                                              
----------------------------------                                                                            
                                                                                                              
Input the rows and columns of first matrix : 2                                                                
2                                                                                                             
                                                                                                              
Input the rows and columns of second matrix : 2                                                               
2                                                                                                             
Input elements in the first matrix :                                                                          
element - [0],[0] : 1                                                                                         
element - [0],[1] : 2                                                                                         
element - [1],[0] : 3                                                                                         
element - [1],[1] : 4                                                                                         
Input elements in the second matrix :                                                                         
element - [0],[0] : 5                                                                                         
element - [0],[1] : 6                                                                                         
element - [1],[0] : 7                                                                                         
element - [1],[1] : 8 

The First matrix is :                                                                                         
                                                                                                              
1       2                                                                                                     
3       4                                                                                                     
The Second matrix is :                                                                                        
                                                                                                              
5       6                                                                                                     
7       8                                                                                                     
The multiplication of two matrices is :                                                                       
                                                                                                              
19      22                                                                                                    
43      50                                          

Flowchart:

C Programming Code Editor:

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