77 lines
1.7 KiB
JavaScript
77 lines
1.7 KiB
JavaScript
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import * as fs from "fs";
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import { PriorityQueue } from "./priority_queue.js";
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const regexp = /Valve ([A-Z]+) has flow rate=(\d+); tunnels? leads? to valves? ([A-Z, ]+)/;
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let valves = {};
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let uv = []; // useful valves
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fs.readFileSync("input", "utf8")
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.trim()
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.split("\n")
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.map(line => {
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let a = line.match(regexp);
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valves[a[1]] = {
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cost: undefined,
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label: a[1],
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links: a[3].split(", "),
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rate: a[2],
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computePathCostTo: function (target) {
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Object.values(valves).forEach(v => v.cost = 0);
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let nq = new PriorityQueue();
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nq.enqueue(this, 0);
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while (true) {
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let n = nq.dequeue();
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if (n.element.label === target) {
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return n.element.cost + 1; // +1 to account for opening the valve
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}
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n.element.links.forEach(l => {
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let v = valves[l];
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if (v.cost === 0) {
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v.cost = n.element.cost + 1;
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nq.enqueue(v, v.cost);
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}
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});
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}
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},
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};
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if (a[2] > 0) {
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uv.push(a[1]);
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}
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});
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let paths = {};
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uv.forEach(v => {
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paths["AA"+v] = valves["AA"].computePathCostTo(v);
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uv.forEach(w => {
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if (v !== w) {
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paths[v+w] = valves[v].computePathCostTo(w);
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paths[w+v] = paths[v+w];
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}
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});
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});
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let max = 0;
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let parcours = [{current: "AA", actives: uv, timeLeft: 30, pressure: 0}];
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for(let i=0; i<parcours.length; i++) {
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let p = parcours[i];
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p.pressure += valves[p.current].rate * p.timeLeft;
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if (max < p.pressure) {
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max = p.pressure;
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}
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p.actives.forEach(v => {
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const cost = paths[p.current+v];
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if (p.timeLeft - cost > 0) {
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parcours.push({
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current:v,
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actives:p.actives.filter(f => f !== v), // this creates a shallow copy
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timeLeft: p.timeLeft - cost,
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pressure: p.pressure,
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});
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}
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});
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}
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console.log(max);
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