Recursive digit addition

[ehsan96696]

Write a recursive function that does the following:

Given a number, add all the digits and display the sum.
Example:
The sum of the number 5432 would be 14.

#include<iostream>

using namespace std;


int add (int input, int sum, int temp, int temp2)
{

 if (input > 1000 )
    {
        temp = 1000;
    }
    else if (input > 100)
    {
        temp = 100;
    }
    else if (input > 10)
    {
        temp = 10;
    }
    else if (input > 0)
    {
        temp = 1;
    }

    sum = input/temp;

    temp2 += sum;

    input = input - (sum * temp);

    add(input, sum, temp, temp2);

    cout << temp2;

}




int main()
{
    int input = 0;
    int sum = 0;
    int temp = 0;
    int temp2 = 0;
    int counter = 4;

    cout << "Please input number." << endl;
    cin >> input;


    add(input, sum, temp, temp2);


}

Every time I run this program recursively it crashes. But if I use a while loop, it works fine. Any help?

[ehsan96696]

Never mind. I got it.

#include<iostream>

using namespace std;


int add (int input, int sum, int temp, int temp2)
{

 if (input > 1000 )
    {
        temp = 1000;
    }
    else if (input > 100)
    {
        temp = 100;
    }
    else if (input > 10)
    {
        temp = 10;
    }
    else if (input > 0)
    {
        temp = 1;
    }
    else
    {
        cout << temp2;
        return 0;
    }

    sum = input/temp;

    temp2 += sum;

    input = input - (sum * temp);

    add(input, sum, temp, temp2);



}




int main()
{
    int input = 0;
    int sum = 0;
    int temp = 0;
    int temp2 = 0;
    int counter = 4;

    cout << "Please input number." << endl;
    cin >> input;


    add(input, sum, temp, temp2);


}

[lastchance]

#include <iostream>
using namespace std;

int sumDigits( int n )
{
   if ( n < 10 ) return n;
   else          return sumDigits( n / 10 ) + n % 10;
}

int main()
{
   int n;
   cout << "Input a positive number: ";   cin >> n;
   cout << "Sum of digits is " << sumDigits( n );
}

Input a positive number: 1234567
Sum of digits is 28