Solved by shepherd_nullptr

#	Title	# Solved	Avg. Tries
1657	두부장수 장홍준	668	2.02
2150	Strongly Connected Component	4,417	2.20
3491	Skyscraper Floors	10	10.80
3653	Movie collection	2,705	2.20
3679	Simple Polygon	909	3.89
5012	Mega Inversions	418	2.14
5820	경주	547	4.82
5822	악어의 지하 도시	112	2.44
6549	Largest Rectangle in a Histogram	10,110	3.69
9126	Cycling	13	5.38
9537	Magical GCD	147	3.23
11280	2-SAT - 3	1,799	1.94
11438	LCA 2	6,698	3.05
11689	GCD(n, k) = 1	3,943	2.50
13007	ntopia	49	1.33
13426	단순 경로의 수열의 도치	8	1.63
14258	XOR 그룹	68	2.51
14749	Grasshopper Route	75	2.56
16044	Prefix Free Code	16	1.75
16229	반복 패턴	186	4.29
17004	Subsequences in Substrings	30	1.17
17157	Hobson’s Trains	22	2.09
18118	7-세그먼트 디스플레이	105	4.31
21148	TripTik	9	3.00
21586	Another Substring Query Problem	32	4.34
21592	Longest Common Substring	66	1.97
21882	Coins on a tree	40	3.85
22911	Hidden Pancakes	44	1.77
23078	Star Trappers	12	3.92
23195	Gene Folding	25	1.80
23196	Landscape Generator	42	1.40
24023	아기 홍윤	323	2.27
24452	交易計画 (Trade Plan)	29	1.93
24602	Tree Hopping	39	2.67
25913	전투 시뮬레이션	37	3.49
26130	Crystal Crosswind	21	1.24
26140	Take On Meme	14	1.14
26141	Where Am I?	23	1.43
27576	Eroding Pillars	5	1.80
27592	Triangle Containment	9	1.11
27889	Exceptional School Name	3,322	1.41
28088	응애(EASY)	147	1.88
28145	A Tree and Two Edges	17	2.35
29772	병사 분배	14	2.43
30947	Cakes	12	1.58
31311	Very Important Edge	10	1.90
31512	Matrix Fraud	12	2.33
31527	Tournament Matchmaking	8	1.63

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