class Solution {
public:
/**
* 进制转换
* @param M int整型 给定整数
* @param N int整型 转换到的进制
* @return string字符串
*/
string solve(int M, int N) {
// write code here
string res = "";
vector<char> rec = {'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
int index = 0, flag=0;
if(M < 0){
M = -M;
flag = 1;
}
while(M > 0){
index = M % N;
M = M / N;
res.push_back(rec[index]);
}
if(flag){
res.push_back('-');
}
reverse(res.begin(), res.end());
return res;
}
};