# include <stdio.h>
# define ROWS 5 
# define COLS 5

/** athroisma kyrias diagoniou **/
int main()
{
	double lesson[ROWS][COLS]={{4,1,2,3,10},
							   {2,4,9,8,7},
		                       {10,7,10,4,1},
		                       {0,0,0,0,0},
		                       {10,2,4,1,6}};
	int i;                      
	double sum=0.0;
	for(i=0;i<ROWS;i++) sum=sum+lesson[i][i];
	printf("Athroisma kyrias diagoniou %lf \n",sum);
 return 0;
}