C Program to calculate the sum of Natural Numbers


Write a program in C to take the input (n) from the user and calculate the sum of all the natural numbers from 1 to n.

How to calculate the sum of natural numbers in C language ?

#include <stdio.h>
int main()
    printf("Abundantcode.com coding sample\n");
    int n, index, result = 0;
    printf("Enter a positive number : ");

    for(index=1; index <= n; ++index)
        result += index; 

    printf("Result = %%d",result);

    return 0;


Abundantcode.com coding sample                                               
Enter a positive number : 4                                                
Result = 10