View Compilation Error

0_0_17880052_2464.cpp: In function 'int main()':
0_0_17880052_2464.cpp:13:30: error: 'memset' was not declared in this scope
         memset(in,0,sizeof in);
                              ^
0_0_17880052_2464.cpp:25:9: error: 'priority_queue' was not declared in this scope
         priority_queue<int ,vector<int> ,greater<int> > q;
         ^
0_0_17880052_2464.cpp:25:24: error: expected primary-expression before 'int'
         priority_queue<int ,vector<int> ,greater<int> > q;
                        ^
0_0_17880052_2464.cpp:30:17: error: 'q' was not declared in this scope
                 q.push(i);
                 ^
0_0_17880052_2464.cpp:33:16: error: 'q' was not declared in this scope
         while(!q.empty())
                ^