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prdoyle/day15.py

Created December 15, 2020 14:20
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Advent of code 2020
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day15.py
#! /usr/bin/python
seed = [0,12,6,13,20,1,17]
end = 30000000
position = 1
most_recent = {}
def process( num ):
global position, most_recent
try:
result = position - most_recent[ num ]
except KeyError:
result = 0
most_recent[ num ] = position
position += 1
return result
for n in seed:
last = process( n )
# We want item at index end-1 (the end'th item), which is the return value from the end-2'th call to process
for n in range( len(seed), end-1 ):
last = process( last )
print( last )
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