/in/foo.cc: In function 'void rotate(int, int&)':
/in/foo.cc:35:30: warning: unused variable 'l' [-Wunused-variable]
     int y=fa[x],z=fa[y],kind,l,r;
                              ^
/in/foo.cc:35:32: warning: unused variable 'r' [-Wunused-variable]
     int y=fa[x],z=fa[y],kind,l,r;
                                ^