Sum of First n natural numbers using C

This program illustrates the more practical example of application of C-loops discussed in previous lession. This program calculates the sum of first n natural numbers. Complete source code and output of program is given here..
Source Code

1: // summation of first n natural numbers

2: #include<stdio.h>

3: 

4: int main(){

5:     int i, sum = 0; //for storing sum, initially must be zero

6:     int n;

7:     printf("Enter the number: ");

8:     scanf("%d",&n);

9: 

10:     for(i = 0; i <=n; i++){

11:         sum = sum + i;

12:     }

13: 

14:     printf("The sum of first %d natural number is %d\n\n", n,sum);

15:     return 0;

16: }

17: 

Output