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day 18 part 1 (with tons of debug)

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Bruno Raoult
2022-01-07 20:33:01 +01:00
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2021/day18/README.txt
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@@ -160,3 +160,31 @@ The final sum is:
The magnitude of this final sum is 4140.
Add up all of the snailfish numbers from the homework assignment in the order they appear. What is the magnitude of the final sum?
Your puzzle answer was 3987.
The first half of this puzzle is complete! It provides one gold star: *
--- Part Two ---
You notice a second question on the back of the homework assignment:
What is the largest magnitude you can get from adding only two of the snailfish numbers?
Note that snailfish addition is not commutative - that is, x + y and y + x can produce different results.
Again considering the last example homework assignment above:
[[[0,[5,8]],[[1,7],[9,6]]],[[4,[1,2]],[[1,4],2]]]
[[[5,[2,8]],4],[5,[[9,9],0]]]
[6,[[[6,2],[5,6]],[[7,6],[4,7]]]]
[[[6,[0,7]],[0,9]],[4,[9,[9,0]]]]
[[[7,[6,4]],[3,[1,3]]],[[[5,5],1],9]]
[[6,[[7,3],[3,2]]],[[[3,8],[5,7]],4]]
[[[[5,4],[7,7]],8],[[8,3],8]]
[[9,3],[[9,9],[6,[4,9]]]]
[[2,[[7,7],7]],[[5,8],[[9,3],[0,2]]]]
[[[[5,2],5],[8,[3,7]]],[[5,[7,5]],[4,4]]]
The largest magnitude of the sum of any two snailfish numbers in this list is 3993. This is the magnitude of [[2,[[7,7],7]],[[5,8],[[9,3],[0,2]]]] + [[[0,[5,8]],[[1,7],[9,6]]],[[4,[1,2]],[[1,4],2]]], which reduces to [[[[7,8],[6,6]],[[6,0],[7,7]]],[[[7,8],[8,8]],[[7,9],[0,6]]]].
What is the largest magnitude of any sum of two different snailfish numbers from the homework assignment?