Solution to retrozeit from DragonCTF 2020

check.py

interesting_data = [0x8b,0x84,0x9a,0x9b,0x9a,0xb1,0xd6,0xaf,0x93,0xb2,0x81,0x8c,0x84,0xab,0x9d,0x9c,0x8e,0xb9,0xb0,0xd9,0xa8,0xa4,0x9c,0x81,0x85,0xa0,0xa6,0xb4,0x87,0x9a,0xbb,0x92,0x96,0xad,0x8c,0xd7,0xb0,0x8d,0x97]
shuffle =          [0x16,0x0c,0x24,0x17,0x13,0x19,0x07,0x09,0x0e,0x23,0x05,0x01,0x18,0x21,0x0d,0x10,0x12,0x1f,0x1a,0x1e,0x22,0x00,0x0f,0x0b,0x08,0x15,0x11,0x02,0x1d,0x1c,0x26,0x03,0x04,0x25,0x14,0x20,0x06,0x1b,0x0a]
interesting_data = interesting_data[:0x27]

m = 38
j = 0
for k in range(len(interesting_data)//2):
	i = shuffle.index(m)	
	uVar1 = shuffle[i]
	uVar2 = interesting_data[i]
	shuffle[i] = shuffle[j]
	interesting_data[i] = interesting_data[j]
	shuffle[j] = uVar1
	interesting_data[j] = uVar2
	m -= 2
	j += 2

j = 1
m = 1
for k in range(len(interesting_data)//2):
	i = shuffle.index(m)
	uVar1 = shuffle[i]
	uVar2 = interesting_data[i]
	shuffle[i] = shuffle[j]
	interesting_data[i] = interesting_data[j]
	shuffle[j] = uVar1
	interesting_data[j] = uVar2
	j += 2
	m += 2

res = []
for i,c in enumerate(interesting_data):
	res.append(chr(((~c & 0xff) ^ i)))

res = ''.join(res)
print(f'{res}')