953.cpp

class Solution {
public:
  bool isAlienSorted(vector<string> &words, string order) {
    size_t indices[26]{};
    for (size_t i = 0; i < order.size(); ++i)
      indices[order[i] - 'a'] = i;
    return is_sorted(words.begin(), words.end(),
                     [&indices](const string &w1, const string &w2) {
                       auto l1 = w1.size(), l2 = w2.size();
                       for (auto i = 0; i < min(l1, l2); ++i) {
                         auto c1 = w1[i], c2 = w2[i];
                         if (c1 != c2)
                           return indices[c1 - 'a'] < indices[c2 - 'a'];
                       }
                       return l1 < l2;
                     });
  }
};