Answer to Question #312252 in C++ for ABdul

Question

Write a program that will ask user to enter a digit character (i.e. ‘0’ or ‘1’ .... or ‘9’). If user

enters a non-digit character then the program should display message to re-enter correct input. If user

enters a correct character (i.e. a digit character) then your program should convert that character to

a same digit but in integer type. Do this for five inputs. Finally, add all digits and display their sum. Do

not use any library function or loops.

Answer 1

#include <iostream>
using namespace std;


int sum(int n) {
    char ch;
    int d;


    if (n == 0) {
        return 0;
    }


    cin >> ch;
    if (ch >= '0' && ch <= '9') {
        d = ch - '0';
        n--;
        return d + sum(n);
    }
    return sum(n);
}


int main() {
    int res = sum(5);


    cout << res;


    return 0;
}