View Compilation Error

0_0_18845854_22576.cpp:18:14: error: unable to find numeric literal operator 'operator""maxm'
 }*null, pool[2maxm];
              ^
0_0_18845854_22576.cpp:18:14: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes
0_0_18845854_22576.cpp: In member function 'void LCT::clear()':
0_0_18845854_22576.cpp:27:11: error: 'pool' was not declared in this scope
   null = &pool[0]; psz = 1; null->ancestor = 0;
           ^
0_0_18845854_22576.cpp: In member function 'Node* LCT::NewNode(int)':
0_0_18845854_22576.cpp:32:14: error: 'pool' was not declared in this scope
   Node *p = &pool[psz++]; 
              ^