C Compiler
// Sum of Natural Numbers Using Recursion
#include <stdio.h>
int sum(int n);
int main()
{
int number, result;
printf(“Enter a positive integer: “);
scanf(“%d”, &number);
result = sum(number);
printf(“sum = %d“, result);
return 0;
}
int sum(int n)
{
if (n != 0)
// sum() function calls itself
return n + sum(n-1);
else
return n;
}