C++ Recursion Code

This is the question:
Your program should:
1. Ask the user for an integer greater than zero.
2. Call a recursive function that calculates the sum of pairs* of digits.
3. Output what those pairs* are and the sum.
*Break up the pairs as follows in these examples: 123 -> 1+23=24, 1234->12+34=46,
12345->1+23+45=69

CAN SOMEONE PLEASE HELP ME?
I have never done programming before

#include <iostream>
using namespace std;

int sum(int x) {
   if (x < 10) return x;
   return x % 10 + sum(x / 10);
}

int main() {
   int n;
   cout << "Enter a number greater than 0: ";
   cin >> n;
   cout << "The digit sum is " << sum(n) << endl;
   return 0;
}

LB (13399)

You are summing individual digits instead of pairs of digits. Your code is close, you just need to change a single number in three places. Focus on lines 5 and 6.

slp99 (13)

Ok so I got that part. I just forgot to change it but I saw that.
I am not sure how to approach the print part

#include <iostream>
using namespace std;

int sum(int x) {
        if (x < 100) return x;
        return x%100 + sum(x/100);
}

int main() {
        int n;
        cout << "Please enter a number greater than 0: ";
        cin >> n;
        cout << "The digit sum is " << sum(n) << endl;



return 0;
}

slp99 (13)

Would I write another function code similar to "sum" but instead it prints or is there an easier way?

slp99 (13)

I think I got it but I am still missing something

int main() {
        int n;
        cout << "Please enter a number greater than 0: ";
        cin >> n;
        int num=n;
        int s=sum(n);
        int r1=0, r2=0, r3=0;
        
                r1=n/100;
                r2=n%100;
        
        cout << "The sum of the pairs of digits is " << endl;
        cout << num << " -> " << r1 << "+" << r2 << "+" << r3 << "=" << sum(n);
        cout << endl;
return 0;
}

This is the output I am getting


Please enter a number greater than 0: 12345
The sum of the pairs of digits is 
12345 -> 123+45+0=69

But I need this
12345->1+23+45=69

Last edited on

LB (13399)

You may find it easier to do the printing from inside your sum function.

slp99 (13)

I am not sure how to do that, can you direct me a bit

LB (13399)

Keep your main function mostly the same - you will only need to print out the = from in main.

In your sum function, print the value that you are summing, and if you are going to recurse, print the plus sign too.

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