OMH 2021 CTF - GRUB solution

solve.py

from constraint import *

if __name__ == '__main__':

	all_chars = tuple(list("RSTUVWXYZ"))
	inp_len = 81
	
	p = Problem()
	p.addVariables(range(0, inp_len), all_chars)

	# t "27,18,9,0,1,2,11,10,""
	p.addConstraint(lambda e: ord("R") <= ord(e), [27])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [27, 18])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [18, 9])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [9, 0])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [0, 1])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [1, 2])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [2, 11])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [11, 10])

	# t "59,50,41,32,40,48,"
	p.addConstraint(lambda e: ord("R") <= ord(e), [59])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [59, 50])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [50, 41])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [41, 32])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [32, 40])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [40, 48])

	# t "51,50,49,48,"
	p.addConstraint(lambda e: ord("R") <= ord(e), [51])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [51, 50])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [50, 49])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [49, 48])

	# t "6,7,8,17,26,"
	p.addConstraint(lambda e: ord("R") <= ord(e), [6])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [6, 7])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [7, 8])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [8, 17])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [17, 26])

	# t "54,64,74,66,76,"
	p.addConstraint(lambda e: ord("R") <= ord(e), [54])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [54, 64])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [64, 74])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [74, 66])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [66, 76])

	# t "79,80,70,"
	p.addConstraint(lambda e: ord("R") <= ord(e), [79])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [79, 80])
	p.addConstraint(lambda *e: ord(e[0]) < ord(e[1]), [80, 70])

	p.addConstraint(AllDifferentConstraint(), range(0, 9))
	p.addConstraint(AllDifferentConstraint(), range(9, 18))
	p.addConstraint(AllDifferentConstraint(), range(18, 27))
	p.addConstraint(AllDifferentConstraint(), range(27, 36))
	p.addConstraint(AllDifferentConstraint(), range(36, 45))
	p.addConstraint(AllDifferentConstraint(), range(45, 54))
	p.addConstraint(AllDifferentConstraint(), range(54, 63))
	p.addConstraint(AllDifferentConstraint(), range(63, 72))
	p.addConstraint(AllDifferentConstraint(), range(72, 81))

	p.addConstraint(AllDifferentConstraint(), [0,  9, 18, 27, 36, 45, 54, 63, 72])
	p.addConstraint(AllDifferentConstraint(), [1, 10, 19, 28, 37, 46, 55, 64, 73])
	p.addConstraint(AllDifferentConstraint(), [2, 11, 20, 29, 38, 47, 56, 65, 74])
	p.addConstraint(AllDifferentConstraint(), [3, 12, 21, 30, 39, 48, 57, 66, 75])
	p.addConstraint(AllDifferentConstraint(), [4, 13, 22, 31, 40, 49, 58, 67, 76])
	p.addConstraint(AllDifferentConstraint(), [5, 14, 23, 32, 41, 50, 59, 68, 77])
	p.addConstraint(AllDifferentConstraint(), [6, 15, 24, 33, 42, 51, 60, 69, 78])
	p.addConstraint(AllDifferentConstraint(), [7, 16, 25, 34, 43, 52, 61, 70, 79])
	p.addConstraint(AllDifferentConstraint(), [8, 17, 26, 35, 44, 53, 62, 71, 80])

	p.addConstraint(AllDifferentConstraint(), [ 0,  1,  2,  9, 10, 11, 18, 19, 20])
	p.addConstraint(AllDifferentConstraint(), [ 3,  4,  5, 12, 13, 14, 21, 22, 23])
	p.addConstraint(AllDifferentConstraint(), [ 6,  7,  8, 15, 16, 17, 24, 25, 26])
	p.addConstraint(AllDifferentConstraint(), [27, 28, 29, 36, 37, 38, 45, 46, 47])
	p.addConstraint(AllDifferentConstraint(), [30, 31, 32, 39, 40, 41, 48, 49, 50])
	p.addConstraint(AllDifferentConstraint(), [33, 34, 35, 42, 43, 44, 51, 52, 53])
	p.addConstraint(AllDifferentConstraint(), [54, 55, 56, 63, 64, 65, 72, 73, 74])
	p.addConstraint(AllDifferentConstraint(), [57, 58, 59, 66, 67, 68, 75, 76, 77])
	p.addConstraint(AllDifferentConstraint(), [60, 61, 62, 69, 70, 71, 78, 79, 80])

	p.addConstraint(AllDifferentConstraint(), [0, 10, 20, 30, 40, 50, 60, 70, 80])
	p.addConstraint(AllDifferentConstraint(), [8, 16, 24, 32, 40, 48, 56, 64, 72])

	solution = p.getSolution()
	
	s = "".join(v for k, v in sorted(solution.items(), key=lambda e: e[0]))
	print(s)

	# Result: VWXZRYSTUUZYTSWXRVTRSVUXWZYSTWRZVYUXYVRSXUZWTXUZYWTRVSRYTWVSUXZWSUXTZVYRZXVUYRTSW
	# Translates to: DOO73LBP6EI461D6HP3N2MM6M953PKJ8MK1A2BGAB8FCIQE9Q4B96E