View Compilation Error

0_0_39797494_30301.cpp: In function 'int main()':
0_0_39797494_30301.cpp:52:17: error: 'memset' was not declared in this scope
   52 |                 memset(head, -1, sizeof head);
      |                 ^~~~~~
0_0_39797494_30301.cpp:2:1: note: 'memset' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    1 | #include <iostream>
  +++ |+#include <cstring>
    2 | using namespace std;