# AoC 2018 Day 9: Marble Madness

### Source: Marble Mania

Part 1: Place marbles in a circle such that each marble is placed by skipping one place except for marbles divisible by 23. For those, don’t place them, skip back 7 places, and remove that marble as well. Add these two marbles to your current score.

Given a specific player count and last marble, what’s the highest score?

# Predator's Gold

On one hand, Predator’s Gold does a solid job of expanding on what was the best part of Mortal Engines: the world building all around mobile cities that eat one another. We get to see a few more cities–both predators and trading cities–along with more details on airships in this world. But the real worldbuilding gold1 is in the parasites that can attach themselves to cities and steal from them. It really makes the cities feel like gigantic living organisms as much as anything, which I’m sure is Reeve’s intention.

On the other hand, I very nearly put Predator’s Gold down several times during the first half of the book. There’s a rather blatant love triangle between Tom, Hester, and Freya (princess of Anchorage–roving city of the north nearly destroyed by a plague in the recent past). It really doesn’t make much sense given Tom and Hester’s relationship at the end of the first book and drags on way too long. Perhaps that’s what some people read the book for… but it’s really not for me.

# AoC 2018 Day 8: Checksum Treeification

### Source: The Sum of Its Parts

Part 1: A custom tree data structure is defined as:

• child count
• child count additional subtrees (recursive)
• metadata count metadata nodes

Calculate the sum of all metadata nodes.

# AoC 2018 Day 7: Job Simulator

### Source: The Sum of Its Parts

Part 1: Given a list of job dependencies (job A must be before job B), determine the order jobs must be done in. Break ties lexicographically.

# AoC 2018 Day 6: Infinite Area Simulator

### Source: Chronal Coordinates

Part 1: Given a list of points, calculate the region of points closest to each point (using Manhattan distance). Return the size of the largest non-infinite region.

# AoC 2018 Day 5: Alchemical reduction

### Source: Alchemical Reduction

Part 1: Given a string, reduce it by removing pairs of letters that are the same letter but different cases. Repeat until you have a minimal string.

# Into the Drowning Deep

Well. That is certainly a book.

It basically reads like Mira Grant thought: you know what’s kind of creepy but doesn’t really have that many books written about them? Mermaids. And just went with it. It works though. Creepy as heck at times and once things start happening around halfway through the book, they really don’t stop. The ending is a bit weak and leaves me wanting more answers, but not enough to ruin the entire book.

# AoC 2018 Day 4: Sleeping on the job

### Source: Repose Record

Part 1: Given a log of guard shifts and times asleep/awake, calculate the guard that was asleep most often and which minute they were most asleep for.

# AoC 2018 Day 3: Regionification

### Source: No Matter How You Slice It

Part 1: Given a list of overlapping regions defined by (left, top, width, height) count how many integer points occur in more than one region.

# The Rook

She came to a decision, pulled her feet out of the mire, and stepped carefully over the ring of bodies that were scattered around her. They were all motionless, and all of them were wearing latex gloves.

So far as openings go, that was certainly one to get my attention.