Answer:
// here is code in C++.
#include <bits/stdc++.h>
using namespace std;
// recursive function to find sum from 1 to n
int recur_Sum(int n)
{ // base condition
if (n <= 1)
return n;
// recursive call
return n + recur_Sum(n - 1);
}
// main function
int main()
{
// variables
int n;
cout<<"Enter a number:";
// read the number
cin>>n;
// print the sum
cout<<"Sum of first "<<n<<" integer from 1 to "<<n<<" is:"<<recur_Sum(n);
return 0;
}
Explanation:
Read a number from user and assign it to variable "n".Call function recur_Sum() with parameter "n".This function will recursively call itself and find the Sum of first n numbers from 1 to n.Then function will return the sum.
Output:
Enter a number:10
Sum of first 10 integer from 1 to 10 is:55
