View Compilation Error

0_0_21279307_4599.cpp: In member function 'void Tree::find(int, int)':
0_0_21279307_4599.cpp:41:23: error: 'u' was not declared in this scope
             find(node[u].child[0],y);
                       ^
0_0_21279307_4599.cpp:43:24: error: 'u' was not declared in this scope
         else if ( node[u].value<y)
                        ^