Puzzle 8990: obvious but tricky

i think i've seen this before!

Author:	csgroup11
Date posted:	11/22/2016 2:05:20 AM
Difficulty (1..5):	1.24 (25 votes)
Popularity:	12 (19 liked, 7 disliked)
Correct solution submitted:	242

Solved by 165 players

_nick (4)	360506 (4)	362171 (4)	404225 (4)	408890 (4)
411209 (4)	413064 (4)	419513 (4)	420792 (4)	422435 (4)
423278 (4)	423398 (4)	428262 (4)	428409 (4)	428994 (4)
429102 (4)	430196 (4)	430479 (4)	442495 (4)	452900 (4)
46324100 (4)	463318 (4)	472225 (4)	475043 (4)	475153 (4)
476445 (4)	483273 (4)	483945 (4)	484573 (4)	484936 (4)
485807 (4)	501021 (4)	antonbootsma (4)	arkangelsk1 (4)	axorion (4)
barajasba1342 (4)	brubru (4)	cowans (4)	dannythorne (4)	edsaw (4)
hero (4)	Inconight (4)	jnpollack (4)	kowka_z (4)	lalala (4)
onqt (4)	padre (4)	pento (4)	ppetrov (4)	scifista42 (4)
scorpio (4)	smylic (4)	sungyeonpark (4)	tadano (4)	TimThree (4)
tiyo (4)	xbox_rob (4)	420227 (5)	496472 (5)	1234alberto (6)
1234angela (6)	365642 (6)	408771 (6)	413937 (6)	485536 (6)
9651410232 (6)	aja2718 (6)	ajayjha25 (6)	alatristecap (6)	amazed (6)
Anabirelle (6)	Angrevol (6)	atzame (6)	benjaminRR (6)	beseech (6)
ceecee (6)	davenger (6)	Davoust (6)	Denyvoda (6)	DonDiego2000 (6)
drwatson (6)	EchelonBCN (6)	Egorovsasa (6)	eversyt (6)	eyTns (6)
fatkiev (6)	Fifiasokon (6)	filiep (6)	fperdu (6)	goetz (6)
goulagman (6)	hilbert (6)	incal1 (6)	jhnesk (6)	KeyoN (6)
kraker (6)	kserikba (6)	leesangwook (6)	libbyhyry (6)	lka_76 (6)
maruska (6)	mathmasterzach (6)	Meddaif99 (6)	milusheva (6)	moul (6)
namayake (6)	Nanaki404 (6)	napo1769 (6)	neenthewiser (6)	p1xm0x (6)
Player (6)	PLeil (6)	prick477 (6)	racello (6)	rahul9493 (6)
razimantv (6)	RCStef (6)	Rezak (6)	rilke (6)	romashka (6)
Sirusc (6)	softa (6)	stijn (6)	talestales (6)	Tharro (6)
tijl (6)	woodsdd1029 (6)	xavierdarmon7 (6)	yannickruault (6)	YoSo (6)
zlejrob (6)	363699 (7)	420829 (7)	421850 (7)	AZAMI (7)
carrben12 (7)	Chirector (7)	dmmn (7)	dougheim (7)	emmagineif (7)
JackHarkness23 (7)	NoThlnG (7)	Ptolo (7)	Rondholz (7)	ssancho (7)
432796 (8)	435027 (8)	451139 (8)	483119 (8)	500974 (8)
502706 (8)	arubaro (8)	belenus (8)	csgroup11 (8)	Dharavi (8)
drmazhar (8)	elicule (8)	giridhar1202 (8)	Jumao (8)	leokaiser (8)
lordofdead38 (8)	qwertymol (8)	silver (8)	twoflower (8)	ym1029sun (8)

Number of commands in the solution is shown in brackets. Shown as ? when not available.