foo.cc: In function 'int main()':
foo.cc:6:10: warning: right operand of comma operator has no effect [-Wunused-value]
  cin>>a,b;
          ^
foo.cc:7:10: error: expected ')' before ';' token
  cout(a+b;)<<endl; 
          ^
foo.cc:7:11: error: expected primary-expression before ')' token
  cout(a+b;)<<endl; 
           ^

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