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diff --git a/assignment3.mdwn b/assignment3.mdwn
index f84d07f9..289f818a 100644
--- a/assignment3.mdwn
+++ b/assignment3.mdwn
@@ -30,7 +30,7 @@ Recall that version 1 style lists are constructed like this (see
 	let iszero = \n. n (\x. false) true in
 	let succ = \n s z. s (n s z) in
 	let mul = \m n s. m (n s) in
-	let pred = \n. iszero n 0 (length (tail (n (\p. make_list junk p) empty))) in
+	let pred = (\shift n. n shift (make\_pair 0 0) get\_snd) (\p. p (\x y. make\_pair (succ x) x)) in
 	let leq = \m n. iszero(n pred m) in
 	let eq = \m n. and (leq m n)(leq n m) in