1
class Solution {
2
 public:
3
  int countGoodSubstrings(string s) {
4
    int cnt = 0, n = s.size();
5
    unordered_map<char, int> map;
6
    for (int i = 0; i < n; i++) {
7
      if (i > 2 and --map[s[i - 3]] == 0) map.erase(s[i - 3]);
8
      map[s[i]]++;
9
      if (map.size() == 3) cnt++;
10
    }
11
    return cnt;
12
  }
13
};