Solved by jdh960401

#	Title	# Solved	Avg. Tries
15650	N과 M (2) STANDARD	48,120	1.35
15651	N과 M (3) STANDARD	39,391	1.49
15652	N과 M (4) STANDARD	40,536	1.27
18870	좌표 압축	35,893	2.51

123