foo.cc: In function 'int main()':
foo.cc:5:29: error: expression list treated as compound expression in initializer [-fpermissive]
  int a,b,max,min,res,lcm(a,b);
                             ^
foo.cc:5:29: warning: left operand of comma operator has no effect [-Wunused-value]
foo.cc:16:9: error: 'lcm' cannot be used as a function
  lcm(a,b)=a*b/min;
         ^
foo.cc:17:15: error: 'lcm' cannot be used as a function
  cout<<lcm(a,b);
               ^

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