(VAR x1 x2 x3 x4 x5 )
(STRATEGY INNERMOST)
(RULES 
        f(s(x1),x2,x3,x4,x5) -> f(x1,x2,x3,x4,x5)
        f(0,s(x2),x3,x4,x5) -> f(x2,x2,x3,x4,x5)
        f(0,0,s(x3),x4,x5) -> f(x3,x3,x3,x4,x5)
        f(0,0,0,s(x4),x5) -> f(x4,x4,x4,x4,x5)
        f(0,0,0,0,s(x5)) -> f(x5,x5,x5,x5,x5)
        f(0,0,0,0,0) -> 0
        
)