[LeetCode]405. Convert a Number to Hexadecimal

[LeetCode]405. Convert a Number to Hexadecimal

题目描述

思路

位运算，每次获取4位，转化为对应的16进制数
因为题目说不会超过32位int并且负数用补码，那可以加入位置计数器，32位二进制表示成十六进制是8位

代码

#include <iostream>
#include <string>

using namespace std;

class Solution {
public:
    string toHex(int num) {
        if (num == 0)
            return "0";
        string hex = "0123456789abcdef", res = "";
        int count = 0;
        while (num && count < 8) {
            res = hex[num & 0xf] + res;
            num >>= 4;
            ++count;
        }
        return res;
    }
};

int main() {
    Solution s;
    cout << s.toHex(-1) << endl;

    system("pause");
    return 0;
}