View Compilation Error

0_0_21354533_18206.cpp: In function 'int main()':
0_0_21354533_18206.cpp:13:15: error: 'class std::priority_queue<std::pair<int, int>, std::vector<std::pair<int, int> >, std::less<std::pair<int, int> > >' has no member named 'clear'
             Q.clear();
               ^