foo.cc: In function 'int main()':
foo.cc:10:5: error: 'string' was not declared in this scope
   10 |     string s;
      |     ^~~~~~
foo.cc:1:1: note: 'std::string' is defined in header '<string>'; did you forget to '#include <string>'?
  +++ |+#include <string>
    1 | using namespace std;
foo.cc:12:5: error: 'cin' was not declared in this scope
   12 |     cin>>s;
      |     ^~~
foo.cc:1:1: note: 'std::cin' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
  +++ |+#include <iostream>
    1 | using namespace std;
foo.cc:12:10: error: 's' was not declared in this scope
   12 |     cin>>s;
      |          ^
foo.cc:24:5: error: 'cout' was not declared in this scope
   24 |     cout<<f[n][0]<<endl;
      |     ^~~~
foo.cc:24:5: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
foo.cc:24:20: error: 'endl' was not declared in this scope
   24 |     cout<<f[n][0]<<endl;
      |                    ^~~~
foo.cc:1:1: note: 'std::endl' is defined in header '<ostream>'; did you forget to '#include <ostream>'?
  +++ |+#include <ostream>
    1 | using namespace std;

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