2D array usage example in C.

gistfile1.c

#define N 500
#define M N/2

#include <stdio.h>

int main(int argc, char **argv) {
  int C[N][N];

  if((&C[M][N+100] == &C[M+1][100]) && (&C[M][N+100] == &(*C)[M*N+N+100])) {
    printf("&C[M][N+100] == &C[M+1][100] == &(*C)[M*N+N+100]\n");
    printf("%p == %p == %p\n", &C[M][N+100], &C[M+1][100], &(*C)[M*N+N+100]);
  }

  return 0;
}