View Compilation Error

0_0_25858209_32692.cpp: In function 'int main()':
0_0_25858209_32692.cpp:49:21: error: 'class std::priority_queue<std::pair<int, int>, std::vector<std::pair<int, int> >, std::greater<std::pair<int, int> > >' has no member named 'clear'
             pq[i-1].clear();
                     ^