Largest 3-Same-Digit Number in String LeetCode solution in C++

1
class Solution {
2
 public:
3
  string largestGoodInteger(string num) {
4
    for (int i = '9'; i >= '0'; i--) {
5
      string s;
6
      s += i;
7
      s += i;
8
      s += i;
9
      // S will be 999 or 888 or 777 or 666 or 555 or 444 or 333 or 222 or 111
10
      // or 000
11
      if (num.find(s) != string::npos) return s;
12
    }
13
    return "";
14
  }
15
};