프로그래머스 124 나라의 숫자

https://programmers.co.kr/learn/courses/30/lessons/12899

#include <iostream>
#include <string>
#include <vector>
using namespace std;
string solution(int n) {
    string answer = "";
    int q = 0, r = 0;
    char ch;
    
    do {
        q = n / 3;
        r = n % 3;
        
        n = (r == 0) ? q - 1 : q;
        ch = (r == 0) ? '4' : r + '0';
        answer += ch;
    } while (q > 0);
    
    return answer;
}
int main() {
    cout << solution(20) << endl;
    return 0;
}