(VAR u v x y )
(STRATEGY INNERMOST)
(RULES 
        f(true,x,y) -> f(gt(x,y),trunc(x),s(y))
        trunc(0) -> 0
        trunc(s(0)) -> 0
        trunc(s(s(x))) -> s(s(trunc(x)))
        gt(0,v) -> false
        gt(s(u),0) -> true
        gt(s(u),s(v)) -> gt(u,v)
        
)