Solved by swstar

#	Title	# Solved	Avg. Tries
27323	직사각형	25,232	1.14
27433	팩토리얼 2	17,856	2.09
27866	문자와 문자열 STANDARD	63,667	1.49
28278	스택 2	15,135	2.69
31403	$A + B - C$	13,580	1.60

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