foo.cc: In function 'int main()':
foo.cc:8:9: warning: left operand of comma operator has no effect [-Wunused-value]
     if(a==234,b==123,n==3)
        ~^~~~~
foo.cc:8:16: warning: right operand of comma operator has no effect [-Wunused-value]
     if(a==234,b==123,n==3)
               ~^~~~~
foo.cc:11:7: warning: left operand of comma operator has no effect [-Wunused-value]
   if(a==234,b==123,n==0)
      ~^~~~~
foo.cc:11:14: warning: right operand of comma operator has no effect [-Wunused-value]
   if(a==234,b==123,n==0)
             ~^~~~~

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