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Program to find Sum of First N Numbers

Below is a program to find sum of the first n numbers using recursion, where the value of n is provided by the user.

#include<stdio.h>
// declaring the recursive function
int getSum(int);

int main()
{
    printf("\n\n\t\tStudytonight - Best place to learn\n\n\n");
    int n, sum;
    printf("\n\nEnter the range of n: ");
    scanf("%d", &n);
    sum = getSum(n);
    printf("\n\nThe sum of first %d numbers is %d\n", n, sum);
    printf("\n\n\t\t\tCoding is Fun !\n\n\n");
    return 0;
}

// function definition
int getSum(int aj)
{
    /*
        static variables hold their values
        till the end of the program
    */
    static int sum = 0;
    if(aj > 0)
    {
        sum = sum + aj;
        getSum(aj-1);
    }
    return sum ;
}

Output:

C program for Sum of first n numbers