foo.cc: In function 'int main()':
foo.cc:84:2: error: 'memset' was not declared in this scope
   84 |  memset(ltn, -1, sizeof(ltn));
      |  ^~~~~~
foo.cc:2:1: note: 'memset' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    1 | #include<iostream>
  +++ |+#include <cstring>
    2 | using namespace std;
foo.cc: In function 'bool bitcheck(int, int)':
foo.cc:33:1: warning: control reaches end of non-void function [-Wreturn-type]
   33 | }
      | ^
foo.cc: In function 'void search(int, int)':
foo.cc:74:9: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result]
   74 |   system("pause");
      |   ~~~~~~^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:101:8: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result]
  101 |  system("pause");
      |  ~~~~~~^~~~~~~~~

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