Diagonales

#include <stdio.h>
#define N 4

void Diagonales (char A[N][N]);

 int main(void)
 {
    char matrix[N][N]=
    {
    {'a','b','c','d'},
    {'e','f','g','h'},
    {'i','j','k','l'},
    {'m','n','o','p'}};
    Diagonales(matrix);
    return 0;
 }

 void Diagonales (char A[N][N]){
    int count = N - 1;
    int i = 0, j = count;
    while (count >= 0){              //Triángulo superior de la matriz y diagonal principal
        while ((j < N) && (i < N)){
            printf("%c", A[i][j]);
            ++j;
            ++i;
        }
        printf("\n");
        --count;
        j = count;
        i = 0;
    }
    j = 0;
    i = count = 1;

    while (count < N){               //Triángulo inferior de la matriz
        while ((j < N) && (i < N)){
            printf("%c", A[i][j]);
            ++i;
            ++j;
        }
        printf("\n");
        ++count;
        i = count;
        j = 0;
    }
 }