View Compilation Error

0_0_33297790_11892.cpp: In function 'int main()':
0_0_33297790_11892.cpp:42:19: error: 'class std::unordered_set<int>' has no member named 'contains'
             if (p.contains(i) && p.contains(i + 2)) {
                   ^
0_0_33297790_11892.cpp:42:36: error: 'class std::unordered_set<int>' has no member named 'contains'
             if (p.contains(i) && p.contains(i + 2)) {
                                    ^