/in/foo.cc: In function 'int main()':
/in/foo.cc:5:10: warning: unused variable 'max' [-Wunused-variable]
  int a,b,max,min,t,r;
          ^~~
/in/foo.cc:5:14: warning: unused variable 'min' [-Wunused-variable]
  int a,b,max,min,t,r;
              ^~~