From UCPOP [which they got from Prodify]
Note: this one is unsolvable because once you get up onto a box, which
is needed for either getting water or getting bananas, there is no
operator for getting back down off the box which you need to do to get
the other one.

(p1)
(p2)
(p3)
(p4)
(p5)
(p6)

(preconds (at monkey p1)(on-floor)(at box p2)(at bananas p3)
	    (at knife p4)(at waterfountain p5)(at glass p6))

(effects (hasbananas) (haswater))