foo.cc: In function 'int main()':
foo.cc:6:3: error: 'cin' was not declared in this scope
   cin>>a>>b>>c;
   ^~~
foo.cc:6:3: note: suggested alternative: 'main'
   cin>>a>>b>>c;
   ^~~
   main
foo.cc:8:2: error: 'cout' was not declared in this scope
  cout<<x;
  ^~~~

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