/in/foo.cc: In function 'long long int gcd(long long int, long long int)':
/in/foo.cc:8:21: warning: left operand of comma operator has no effect [-Wunused-value]
         return (b,a%b);
                     ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:14:13: warning: unused variable 'd' [-Wunused-variable]
     int t,s,d,i;
             ^
/in/foo.cc:14:15: warning: unused variable 'i' [-Wunused-variable]
     int t,s,d,i;
               ^