/in/foo.cc: In function 'int main()':
/in/foo.cc:31:7: warning: unused variable 'red' [-Wunused-variable]
   int red,yellow,blue,ry,rb,yb,ryb;
       ^~~
/in/foo.cc:31:11: warning: unused variable 'yellow' [-Wunused-variable]
   int red,yellow,blue,ry,rb,yb,ryb;
           ^~~~~~
/in/foo.cc:31:18: warning: unused variable 'blue' [-Wunused-variable]
   int red,yellow,blue,ry,rb,yb,ryb;
                  ^~~~