59 lines
1.3 KiB
Python
59 lines
1.3 KiB
Python
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def read_file():
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with open("input.txt","r") as f:
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return [int(x) for x in f.read().split('\n')]
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def part1(adapters):
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jolts = [0] + sorted(adapters) # j(port) = 0
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d1 = 0
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d3 = 1 # j(device) = max + 3
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i = 0
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while i <= len(adapters):
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difference = jolts[i] - jolts[i-1]
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if difference == 1:
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d1 += 1
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elif difference == 2:
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d2 += 1
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elif difference == 3:
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d3 += 1
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i += 1
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return d1 * d3
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"""
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def find_all_paths(graph, start, end, path=[]):
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path = path + [start]
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if start == end:
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return [path]
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if start not in graph:
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return []
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paths = []
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for node in graph[start]:
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if node not in path:
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newpaths = find_all_paths(graph, node, end, path)
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for newpath in newpaths:
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paths.append(newpath)
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return paths
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"""
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def part2(adapters):
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jolts = [0] + sorted(adapters)
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from collections import Counter
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dp = Counter()
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dp[0] = 1
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jolts = sorted(adapters)
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jolts.append(jolts[-1] + 3)
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for j in jolts:
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dp[j] = dp[j-1] + dp[j-2] + dp[j-3]
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return dp[jolts[-1]]
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"""
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graph = {}
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for i, joltage in enumerate(jolts):
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graph[joltage] = [x for x in jolts[i+1:i+4] if 0 < x - joltage <= 3] # scan next 3, assuming diff of +1 +1 +1 at most
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return len( find_all_paths( graph, 0, max(jolts) ) )
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"""
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def main():
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adapters = read_file()
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print(part1(adapters), part2(adapters))
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if __name__ == "__main__":
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main()
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