matrix multiplication in c

#include <stdio.h>

void multiplyMatrix(int mat1[][3], int mat2[][3], int res[][3]) {
    int i, j, k;
    for (i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            res[i][j] = 0;
            for (k = 0; k < 3; k++) {
                res[i][j] += mat1[i][k] * mat2[k][j];
            }
        }
    }
}

void displayMatrix(int mat[][3]) {
    int i, j;
    for (i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            printf("%d ", mat[i][j]);
        }
        printf("\n");
    }
}

int main() {
    int mat1[3][3] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
    int mat2[3][3] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
    int res[3][3];

    multiplyMatrix(mat1, mat2, res);

    printf("Resultant matrix:\n");
    displayMatrix(res);

    return 0;
}

Note: This code multiplies two 3x3 matrices and displays the resultant matrix. You can modify the mat1 and mat2 arrays to multiply different matrices.