AoC 2021 Day 21: Dicinator

Source: Dirac Dice

Part 1: Play a simple game (describe below) with a loaded D100 (that always rolls 1, 2, 3, … 99, 100, 1, …). Return the score of the losing player times the number of times the die was rolled.

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AoC 2021 Day 19: Point Matchinator

Source: Snailfish

Part 1: You will be given a series of Scanners, each of which will tell you the location (from their point of view) of a series of Beacons. Each Scanner may be flipped or rotated in increments of 90 degrees in any direction. Determine where each Scanner and Beacon is by overlaying the maps (with at least pairwise 12 matches).

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AoC 2021 Day 17: Pew-Pewinator

Source: Trick Shot

Part 1: Simulate a projectile with an integer initial velocity (x, y), air resistance that tries to reduce x-velocity to 0, and gravity that increases y-velocity by 1 each time. Given a target range, find the highest point reached by a projectile that ends a tick (not one that crosses over) within the target area.

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AoC 2021 Day 14: Polymerizationinator

Source: Extended Polymerization

Part 1: Given a complete function f(a, b) -> c where any string ab becomes acb and an input string, apply the function at the same time to every (overlapping) pair of letters. Repeat this time times. Report the difference in counts between the most and least common letters in the final situation.

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