View Compilation Error

0_0_23043361_7449.cpp: In function 'int main()':
0_0_23043361_7449.cpp:34:19: error: 'class std::priority_queue<P>' has no member named 'front'
             P p=q.front();
                   ^
0_0_23043361_7449.cpp:43:34: error: 'class std::priority_queue<P>' has no member named 'front'
             while(!q.empty()&&(q.front().c==c)){
                                  ^
0_0_23043361_7449.cpp:44:23: error: 'class std::priority_queue<P>' has no member named 'front'
                 P p=q.front();
                       ^