Advent of Code 2015 - Day 23: Opening the Turing Lock

Part 1 Description Little Jane Marie just got her very first computer for Christmas from some unknown benefactor. It comes with instructions and an example program, but the computer itself seems to be malfunctioning. She's curious what the program does, and would like you to help her run it. The manual explains that the computer supports two registers and six instructions (truly, it goes on...

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Advent of Code 2015 - Day 18: Like a GIF For Your Yard

Part 1 Description After the million lights incident, the fire code has gotten stricter: now, at most ten thousand lights are allowed. You arrange them in a 100x100 grid. Never one to let you down, Santa again mails you instructions on the ideal lighting configuration. With so few lights, he says,...

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Advent of Code 2015 - Day 17: No Such Thing as Too Much

Part 1 Description The elves bought too much eggnog again - 150 liters this time. To fit it all into your refrigerator, you'll need to move it into smaller containers. You take an inventory of the capacities of the available containers. For example, suppose you have containers of size 20, 15,...

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Advent of Code 2015 - Day 16: Aunt Sue

Part 1 Description Your Aunt Sue has given you a wonderful gift, and you'd like to send her a thank you card. However, there's a small problem: she signed it "From, Aunt Sue". You have 500 Aunts named "Sue". So, to avoid sending the card to the wrong person, you need to figure out which Aunt...

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Advent of Code 2015 - Day 15: Science for Hungry People

Part 1 Description Today, you set out on the task of perfecting your milk-dunking cookie recipe. All you have to do is find the right balance of ingredients. Your recipe leaves room for exactly 100 teaspoons of ingredients. You make a list of the remaining ingredients you could use to finish the...

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Advent of Code 2015 - Day 14: Reindeer Olympics

Part 1 Description This year is the Reindeer Olympics! Reindeer can fly at high speeds, but must rest occasionally to recover their energy. Santa would like to know which of his reindeer is fastest, and so he has them race. Reindeer can only either be flying (always at their top speed) or resting...

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Advent of Code 2015 - Day 13: Knights of the Dinner Table

Part 1 Description In years past, the holiday feast with your family hasn't gone so well. Not everyone gets along! This year, you resolve, will be different. You're going to find the optimal seating arrangement and avoid all those awkward conversations. You start by writing up a list of everyone...

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Advent of Code 2015 - Day 12: JSAbacusFramework.io

Part 1 Description Santa's Accounting-Elves need help balancing the books after a recent order. Unfortunately, their accounting software uses a peculiar storage format. That's where you come in. They have a JSON document which contains a variety of things: arrays ([1,2,3]), objects ({"a":1, "b":2}),...

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Advent of Code 2015 - Day 11: Corporate Policy

Part 1 Description Santa's previous password expired, and he needs help choosing a new one. To help him remember his new password after the old one expires, Santa has devised a method of coming up with a password based on the previous one. Corporate policy dictates that passwords must be exactly eight lowercase letters (for security reasons), so he finds his new password by incrementing his...

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Advent of Code 2015 - Day 10: Elves Look, Elves Say

Part 1 Description Today, the Elves are playing a game called look-and-say. They take turns making sequences by reading aloud the previous sequence and using that reading as the next sequence. For example, 211 is read as "one two, two ones", which becomes 1221 (1 2, 2 1s). Look-and-say sequences are generated iteratively, using the previous value as input for the next step. For each step,...

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