How to pass a 2D array as a parameter in C?

A 2-D array can be easily passed as a parameter to a function in C. A program that demonstrates this when both the array dimensions are specified globally is given as follows.

Example

 Live Demo

#include <stdio.h> const int R = 4; const int C = 3; void func(int a[R][C]) {    int i, j;    for (i = 0; i < R; i++)    for (j = 0; j < C; j++)    a[i][j] += 5; ; } int main() {    int a[R][C];    int i, j;    for (i = 0; i < R; i++)    for (j = 0; j < C; j++)    a[i][j] = i+j;    printf("Initial 2-D array is:
");    for (i = 0; i < R; i++) {       for (j = 0; j < C; j++) {          printf("%d ", a[i][j]);       }       printf("
");    }    func(a);    printf("Modified 2-D array is:
");    for (i = 0; i < R; i++) {       for (j = 0; j < C; j++) {          printf("%d ", a[i][j]);       }       printf("
");    }    return 0; }

Output

The output of the above program is as follows.

Initial 2-D array is: 0 1 2 1 2 3 2 3 4 3 4 5 Modified 2-D array is: 5 6 7 6 7 8 7 8 9 8 9 10