foo.cc: In function 'int main()':
foo.cc:8:30: error: 'setprecision' was not declared in this scope
    8 |                 cout<<fixed<<setprecision(2)<<-n;
      |                              ^~~~~~~~~~~~
foo.cc:10:30: error: 'setprecision' was not declared in this scope
   10 |                 cout<<fixed<<setprecision(2)<<n;
      |                              ^~~~~~~~~~~~

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