NIELIT M3-R4: Q.No. 7(a) July 2013

M3-R4: July 2013 (O-Level)

Q. 7(a):
Define recursion. Write a complete program to evaluate the given series using recursive function sum( ). Here n is user dependent.
1 + 2 + 3 +…+ n

Ans:

Recursion: A recursive function is a function that calls itself repeatedly.

Program to evaluate sum of the given series using recursive function:

#include <stdio.h>
#include <conio.h>

int sum(int);
 
void main(){
    int n, s;
    printf("\nEnter n: ");
    scanf("%d", &n);
    s = sum(n);
    printf("\nSum = %d", s);
    getch();
}

int sum(int n){
    if(n == 1)
        return 1;
    
    return (n + sum(n-1));
}