/in/foo.cc: In function 'int main()':
/in/foo.cc:5:12: warning: unused variable 'max' [-Wunused-variable]
  int a,b,t,max,min,r;
            ^~~
/in/foo.cc:5:16: warning: unused variable 'min' [-Wunused-variable]
  int a,b,t,max,min,r;
                ^~~
/in/foo.cc:7:3: warning: 'b' is used uninitialized in this function [-Wuninitialized]
  t=a*b;
  ~^~~~