blob: b255acafa9ed00a24d3b80e1bf2177675e66775d (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
import { JSONSet } from "@/utils";
type Point = {
x: number;
y: number;
};
const distance = (p1: Point, p2: Point) =>
Math.sqrt(Math.pow(p2.x - p1.x, 2) + Math.pow(p2.y - p1.y, 2));
const isDiagAdj = (p1: Point, p2: Point) => distance(p1, p2) <= Math.sqrt(2);
export const main = async (lines: string[]): Promise<number | string> => {
const knots: Point[] = Array(2)
.fill(null)
.map(() => ({ x: 0, y: 0 }));
const visited: JSONSet<Point> = new JSONSet();
visited.add(knots[0]);
for (const step of lines) {
const [dir, steps_s] = step.split(" ");
const steps = parseInt(steps_s);
for (let i = 0; i < steps; ++i) {
if (dir === "U") knots[0].y += 1;
if (dir === "L") knots[0].x -= 1;
if (dir === "R") knots[0].x += 1;
if (dir === "D") knots[0].y -= 1;
for (let knotidx = 1; knotidx < knots.length; knotidx++) {
const [head, tail] = [knots[knotidx - 1], knots[knotidx]];
if (!isDiagAdj(head, tail)) {
if (dir === "U") {
tail.x = head.x;
tail.y = head.y - 1;
}
if (dir === "L") {
tail.x = head.x + 1;
tail.y = head.y;
}
if (dir === "R") {
tail.x = head.x - 1;
tail.y = head.y;
}
if (dir === "D") {
tail.x = head.x;
tail.y = head.y + 1;
}
visited.add(tail);
}
}
}
}
return visited.size;
};
//
const isrun = process.argv.length > 1 && process.argv[1] === import.meta.path;
if (isrun) {
const file = Bun.file("./problem.txt");
const text = await file.text();
const lines = text.split("\n").filter((x) => x && x.length);
console.log("=== COMPUTATION ===\n");
const answer = await main(lines);
console.log("\n=== /COMPUTATION ===\n");
console.log("=== ANSWER TO P1 ===");
console.log(answer);
}
|
