View Compilation Error

0_0_34339338_14283.cpp: In function 'int main()':
0_0_34339338_14283.cpp:38:6: error: 'A' was not declared in this scope
      A.push(HP);
      ^
0_0_34339338_14283.cpp:40:6: error: 'B' was not declared in this scope
      B.push(HP);
      ^
0_0_34339338_14283.cpp:42:6: error: 'C' was not declared in this scope
      C.push(HP);
      ^
0_0_34339338_14283.cpp:48:11: error: 'A' was not declared in this scope
      if (!A.empty())
           ^
0_0_34339338_14283.cpp:58:11: error: 'B' was not declared in this scope
      if (!B.empty())
           ^
0_0_34339338_14283.cpp:68:11: error: 'C' was not declared in this scope
      if (!C.empty())
           ^