YES
exiting with thread!
(VAR x )
(RULES 
        w(u(w(x))) -> u(w(u(u(x))))
        w(u(u(u(u(w(x)))))) -> u(u(w(u(u(u(u(x)))))))
        w(u(u(u(u(u(w(x))))))) -> u(u(x))
        w(u(u(u(w(x))))) -> u(u(u(u(w(u(x))))))
        a(x) -> u(u(u(u(u(u(x))))))
        w(u(u(u(u(u(u(w(x)))))))) -> u(u(u(w(u(u(u(u(u(x)))))))))
        u(u(u(u(u(u(u(x))))))) -> x
        w(w(x)) -> u(u(u(u(u(u(w(u(u(u(x))))))))))
        v(x) -> u(u(u(u(u(w(u(u(u(u(x))))))))))
        c(x) -> u(u(u(u(u(w(u(u(u(u(u(x)))))))))))
        w(u(u(w(x)))) -> u(u(u(u(u(w(u(u(u(u(u(u(x))))))))))))
        b(x) -> u(w(x))
        
)