View Compilation Error

0_0_39129531_27781.cpp: In function 'int Main()':
0_0_39129531_27781.cpp:39:17: error: 'memset' was not declared in this scope
   39 |                 memset(tree, 0, sizeof tree);
      |                 ^~~~~~
0_0_39129531_27781.cpp:6:1: note: 'memset' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    5 | #include <cstdio>
  +++ |+#include <cstring>
    6 | #define debug(a) cerr<<"Line: "<<__LINE__<<" "#a<<endl