n = 19
visitors = '16 11 5 7 15 18 6 13 9 10 14 12 2 19 4 17 3'.split(' ')
missed = list(filter(lambda x: str(x) not in visitors, range(1, n+1)))
print(missed)
Cm4gPSAxOQp2aXNpdG9ycyA9ICcxNiAxMSA1IDcgMTUgMTggNiAxMyA5IDEwIDE0IDEyIDIgMTkgNCAxNyAzJy5zcGxpdCgnICcpCm1pc3NlZCA9IGxpc3QoZmlsdGVyKGxhbWJkYSB4OiBzdHIoeCkgbm90IGluIHZpc2l0b3JzLCByYW5nZSgxLCBuKzEpKSkKcHJpbnQobWlzc2VkKQ==