C Program to find sum of lower triangle matrix

Program

#include<stdio.h>
void main()
{
	int i, j, a[10][10], sum, rows, columns;
	printf("Enter the number of Rows :\t");
	scanf("%d", &rows);
	printf("Enter the number of Columns :\t");
	scanf("%d", &columns);
	for (i = 0; i < rows; i++)
	{
		for (j = 0; j < columns; j++)
		{
			printf("Enter the Element a[%d][%d] :\t", i, j);
			scanf("%d", &a[i][j]);
		}
	}
	for (i = 0; i < rows; i++)
	{
		for (j = 0; j < columns; j++)
		{
			printf("%d\t", a[i][j]);
		}
		printf("\n");
	}
	sum = 0;
	for (i = 0; i < rows; i++)
	{
		for (j = 0; j < columns; j++)
		{
			if (i > j)
			{
				sum = sum + a[i][j];
			}
		}
	}
	printf("\nSum of Lower Triangle Elements : %d\n", sum);
}

Output

Enter the number of Rows :	3
Enter the number of Columns :	3
Enter the Element a[0][0] :	65
Enter the Element a[0][1] :	12
Enter the Element a[0][2] :	6 
Enter the Element a[1][0] :	32
Enter the Element a[1][1] :	90
Enter the Element a[1][2] :	76
Enter the Element a[2][0] :	45
Enter the Element a[2][1] :	76
Enter the Element a[2][2] :	1
65	12	6	
32	90	76	
45	76	1	
Sum of Lower Triangle Elements : 153