foo.cc:1:1: error: 'include' does not name a type; did you mean '__has_include'?
 include<bits/stdc++.h>
 ^~~~~~~
 __has_include
foo.cc: In function 'int main()':
foo.cc:5:2: error: 'cin' was not declared in this scope
  cin>>n;
  ^~~
foo.cc:5:2: note: suggested alternative: 'main'
  cin>>n;
  ^~~
  main
foo.cc:15:3: error: 'cout' was not declared in this scope
   cout<<ans<<endl;
   ^~~~
foo.cc:15:14: error: 'endl' was not declared in this scope
   cout<<ans<<endl;
              ^~~~
foo.cc:15:14: note: suggested alternative: 'enum'
   cout<<ans<<endl;
              ^~~~
              enum
foo.cc:8:10: warning: unused variable 'ibuy' [-Wunused-variable]
  int i=1,ibuy;
          ^~~~

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