Daily Practice 12

504. 七进制数

简单的模拟

class Solution {
  public:
    string convertToBase7(int num) {
        if (num == 0)
            return "0";
        bool is_neg = false;
        if (num < 0) {
            num = -num;
            is_neg = true;
        }
        string res = "";
        char t;
        while (num) {
            t = num % 7 + '0';
            res = t + res;
            num /= 7;
        }
        if (is_neg)
            res = "-" + res;
        return res;
    }
};