Find the sum of upper & lower traiangular elements Using C

# include <stdio.h>
# include <conio.h>

void main()
{
int mat[10][10] ;
int i, j, size, upper = 0, lower = 0 ;
clrscr() ;
printf("Enter size of the square matrix : ") ;
scanf("%d", &size) ;
printf("\nEnter the elements of the matrix : \n\n") ;
for(i = 0 ; i < size ; i++)
for(j = 0 ; j < size ; j++)
scanf("%d", &mat[i][j]) ;
printf("\nThe upper triangular matrix is : \n\n") ;
for(i = 0 ; i < size ; i++)
{
for(j = 0 ; j < size ; j++)
{
if(i <= j)
{
printf("%d\t", mat[i][j]) ;
upper = upper + mat[i][j] ;
}
else
printf("\t") ;
}
printf("\n") ;
}
printf("\nThe lower triangular matrix is : \n\n") ;
for(i = 0 ; i < size ; i++)
{
for(j = 0 ; j < size ; j++)
{
if(j <= i)
{
printf("%d\t", mat[i][j]) ;
lower = lower + mat[i][j] ;
}
else
printf("\t") ;
}
printf("\n") ;
}
printf("\nThe sum of upper triangular elements is : %d\n",upper);
printf("\nThe sum of lower triangular elements is : %d", lower) ;
getch() ;
}

RUN 1 :
~~~~~~~
Enter size of the square matrix : 3
Enter the elements of the matrix :
1 2 3
4 5 6
7 8 9
The upper triangular matrix is :
1 2 3
5 6
9
The lower triangular matrix is :
1
4 5
7 8 9
The sum of upper triangular elements is : 26
The sum of lower triangular elements is : 34