C Program to calculate Sum of Natural Numbers

#include <stdio.h>

#include<conio.h>

void main() 

{

    int n, i, sum = 0;

    clrscr();

    printf("Enter an integer\n ");

    scanf("%d", &n);

    for (i = 1; i <= n; ++i) 

  {

        sum = sum+i;

    }

    printf("Sum of %d Natural Numbers = %d", n, sum);

    getch();

}

Output

Enter an integer

5

Sum of 5 Natural Numbers = 15