View Compilation Error

0_0_25830930_13242.cpp:17:1: error: 'priority_queue' does not name a type
 priority_queue<node>q;
 ^
0_0_25830930_13242.cpp: In function 'int main()':
0_0_25830930_13242.cpp:30:23: error: 'memset' was not declared in this scope
   memset(b,0,sizeof(b));
                       ^
0_0_25830930_13242.cpp:37:4: error: 'q' was not declared in this scope
    q.push(p);
    ^
0_0_25830930_13242.cpp:47:11: error: 'q' was not declared in this scope
    node u=q.top();
           ^
0_0_25830930_13242.cpp:62:10: error: 'q' was not declared in this scope
   while(!q.empty())
          ^