The avatar for @emanuelfeld
Emanuel Feld
Published
Advent of Code 2018
Edited
Dec 8, 2018
Advent of Code 2018
[Day 25](https://adventofcode.com/2018/day/25)[Day 18](https://adventofcode.com/2018/day/18)[Day 21](https://adventofcode.com/2018/day/21)Day 19[Day 16](https://adventofcode.com/2018/day/16)[Day 14](https://adventofcode.com/2018/day/14)[Day 13](https://adventofcode.com/2018/day/13)[Day 12](https://adventofcode.com/2018/day/12)[Day 11](https://adventofcode.com/2018/day/11)[Day 10](https://adventofcode.com/2018/day/10)[Day 9](https://adventofcode.com/2018/day/9)[Day 8](https://adventofcode.com/2018/day/8)[Day 7](https://adventofcode.com/2018/day/7)
[Day 6](https://adventofcode.com/2018/day/6)
[Day 5](https://adventofcode.com/2018/day/5)[Day 4](https://adventofcode.com/2018/day/4)[Day 3](https://adventofcode.com/2018/day/3)Advent of Code: [Day 2](https://adventofcode.com/2018/day/2)[Day 1](https://adventofcode.com/2018/day/1)
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centroids = input.split('\n').map(line => line.match(/\d+/g).map(Number))
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function manhattanDistance (a, b) {
return Math.abs(a[0] - b[0]) + Math.abs(a[1] - b[1]);
}
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largestFiniteArea = {
let unboundedCentroids = new Set();
let centroidAreas = {}

for (let x = minX; x <= maxX; x++) {
for (let y = minY; y <= maxY; y++) {
// Get the sorted distances from (x, y) to each centroid
const distances = centroids.map(c => [manhattanDistance(c, [x, y]), c]).sort((a, b) => a[0] - b[0]);
// Don't count points equidistance to >1 centroid
if (distances[0][0] !== distances[1][0]) {
centroidAreas[distances[0][1]] = (centroidAreas[distances[0][1]] || 0) + 1;
}

// If a border point is assigned to a centroid, that centroid's region is infinite
if (x === minX || y === minY || x === maxX || y === maxY) {
unboundedCentroids.add(distances[0][1]);
}
}
}
for (const centroid of unboundedCentroids) {
delete centroidAreas[centroid];
}
return Math.max(...Object.entries(centroidAreas).map(e => e[1]));
}
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safeCoordinateCount = {
let safeCoordinateCount = 0;
for (let x = minX; x <= maxX; x++) {
for (let y = minY; y <= maxY; y++) {
// Sum point (x, y)'s distance to each centroid
const totalDistance = centroids.map(c => manhattanDistance(c, [x, y])).reduce((sum, n) => sum + n);
if (totalDistance < totalDistanceCap) {
safeCoordinateCount++;
}
}
}
return safeCoordinateCount;
}
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