#include <stdio.h>
#define LEN 3
int main()
{
    int matrix[][LEN] = { { 1, 2, 3 }, 
	                      { 5, 6, 7 }, 
						  { 8, 7, 9 } };
	
	int rows = sizeof(matrix) / sizeof(matrix[0]);
    int cols = sizeof(matrix[0]) / sizeof(matrix[0][0]);
	// left
    for (int i = 0; i < rows; i++) {
		printf("%3d", matrix[i][i]); 
    }
	printf("\n");
	
	// right
    for (int i = 0, j  = cols - 1; i < rows; i++, j--) {
		printf("%3d", matrix[i][j]); 
    }
	printf("\n");
	        
    return 0;
}
   
   
   
   
/*
run:
   
  1  6  9
  3  6  8
  
*/