AoC-23/Day17/Part1.js

64 lines
1.7 KiB
JavaScript

import { readFileSync } from "fs";
const t0 = performance.now();
const input = readFileSync("input.txt")
.toString()
.split(/\r*\n/)
.filter((e) => e.length > 0)
.map((a, j) => a
.split("")
.map((b, i) => ({
c: +b,
x: i,
y: j,
g: 0,
h: 0,
})));
const man_dist = (a, b) => Math.abs(b.x - a.x) + Math.abs(b.y - a.y);
const start = input[0][0];
const end = input.slice(-1)[0].slice(-1)[0];
const open = [start], closed = [];
while (open.length > 0) {
let record = {};
for (const [index, next] of Object.entries(open)) {
const distance = next.g + next.h;
if (record?.distance ?? -1 < distance) {
record.distance = distance;
record.index = +index;
}
}
const current = open.splice(record.index, 1)[0];
closed.push(current);
if (current === end) break;
for (let j = -1; j < 2; j++)
for (let i = -1; i < 2; i++) {
if (!(i === 0 ^ j === 0)) continue;
const nx = current.x + i;
const ny = current.y + j;
if (!input[ny]) continue;
const next = input[ny][nx];
if (!next || closed.includes(next)) continue;
const nd = current.g + next.c;
if (open.includes(next)) {
if (nd < next.g)
next.g = nd;
continue;
}
next.g = nd;
next.h = man_dist(next, end);
open.push(next);
}
}
console.log(end.g);
const t1 = performance.now();
console.log(`Runtime: ${t1 - t0}ms`);