foo.cc: In function 'int main()':
foo.cc:4:9: error: 'cin' was not declared in this scope
    4 |         cin>>a;
      |         ^~~
foo.cc:6:9: error: 'cout' was not declared in this scope
    6 |         cout<<fixed<<setprecision(1)<<g<<endl;
      |         ^~~~
foo.cc:6:15: error: 'fixed' was not declared in this scope
    6 |         cout<<fixed<<setprecision(1)<<g<<endl;
      |               ^~~~~
foo.cc:6:22: error: 'setprecision' was not declared in this scope
    6 |         cout<<fixed<<setprecision(1)<<g<<endl;
      |                      ^~~~~~~~~~~~
foo.cc:6:42: error: 'endl' was not declared in this scope
    6 |         cout<<fixed<<setprecision(1)<<g<<endl;
      |                                          ^~~~

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