普通的进制转换模板题

#include <iostream>
#include <algorithm>
using namespace std;
string d2r(int n, int r){
	string s = "";while (n > 0){
		int t = n % r;n /= r;
		if (t < 10)s = char(t + '0') + s;
		else s = char(t - 10 + 'A') + s;
	}return s;
}int main() {int n, m;
	while (cin >> n >> m){
		if (n == 0)cout << 0;
		else{if (n != abs(n)) {
				cout << "-";
				n = abs(n);
			}cout << d2r(n, m);
		}cout << endl;
	}
}