View Compilation Error

0_0_28813253_2607.cpp: In function 'void bfs()':
0_0_28813253_2607.cpp:22:2: error: 'queue' was not declared in this scope
  queue<int> q;
  ^
0_0_28813253_2607.cpp:22:8: error: expected primary-expression before 'int'
  queue<int> q;
        ^
0_0_28813253_2607.cpp:23:2: error: 'q' was not declared in this scope
  q.push(1);
  ^
0_0_28813253_2607.cpp: In function 'int lca(int, int)':
0_0_28813253_2607.cpp:48:11: error: 'swap' was not declared in this scope
   swap(x,y);
           ^