C Program to Find Sum of Natural Number

In this program, you'll learn how to find sum of natural numbers. User have to enter the positive integer.

Source Code

#include <stdio.h>
#include<conio.h>
void main( )
{
    int n, i, sum = 0;
    printf("Enter a positive integer: ");
    scanf("%d",&n);
    for(i=1; i <= n; ++i)
    {
        sum = sum + i;
    }
    printf("Sum = %d",sum);
    getch( );
}

Output

Enter a positive integer: 100
Sum = 5050