Solved by rubytest

#	Title	# Solved	Avg. Tries
1000	A+B STANDARD	326,539	2.59
1001	A-B STANDARD	280,682	1.45
1008	A/B STANDARD	232,061	2.90
2557	Hello World STANDARD	360,666	2.54
10998	A×B STANDARD	234,302	1.30
16904	집합과 쿼리	41	1.98

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