52 lines
1.1 KiB
JavaScript
52 lines
1.1 KiB
JavaScript
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import { readFileSync } from "fs";
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const input = readFileSync("movements.txt", "utf-8");
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function isTailAdjacentToHead(head, tail) {
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if(Math.abs(tail.x - head.x) > 1) return false;
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if(Math.abs(tail.y - head.y) > 1) return false;
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return true;
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}
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const head = { x: 0, y: 0}, tail = { x: 0, y: 0 };
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const visited = new Map([[ `0:0`, true ]]);
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input.split('\n').forEach(line => {
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const operations = line.split(' ');
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let x = 0, y = 0;
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switch(operations[0]) {
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case "U":
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y++;
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break;
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case "D":
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y--;
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break;
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case "L":
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x--;
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break;
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case "R":
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x++;
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break;
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}
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for(let i = 0; i < parseInt(operations[1]); i++) {
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const oldHead = {};
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oldHead.x = head.x;
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oldHead.y = head.y;
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head.x += x;
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head.y += y;
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if(!isTailAdjacentToHead(head, tail)) {
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tail.x = oldHead.x;
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tail.y = oldHead.y;
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visited.set(`${tail.x}:${tail.y}`, true);
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}
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}
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});
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console.log(visited.size);
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