View Compilation Error

0_0_37450222_29891.cpp:37:11: error: variable or field 'Free' declared void
 void Free(tr* p)
           ^
0_0_37450222_29891.cpp:37:11: error: 'tr' was not declared in this scope
0_0_37450222_29891.cpp:37:15: error: 'p' was not declared in this scope
 void Free(tr* p)
               ^
0_0_37450222_29891.cpp: In function 'int main()':
0_0_37450222_29891.cpp:61:15: error: 'Free' was not declared in this scope
     Free(&root);
               ^