1
class Solution {
2
  int uf[26];
3
  int find(int x) {
4
    return uf[x] == x ? x : (uf[x] = find(uf[x]));
5
  }
6

7
 public:
8
  bool equationsPossible(vector<string> &equations) {
9
    for (int i = 0; i < 26; ++i) uf[i] = i;
10
    for (auto e : equations) {
11
      if (e[1] == '=') uf[find(e[0] - 'a')] = find(e[3] - 'a');
12
    }
13
    for (auto e : equations) {
14
      if (e[1] == '!' && find(e[0] - 'a') == find(e[3] - 'a')) return false;
15
    }
16
    return true;
17
  }
18
};