AoC 2019 - day 3

AoC_2019_d3.js

const INPUT = `
COPY & PASTE HERE INPUT LINES
`;

const [firstLine,secondLine]=INPUT.trim().split`\n`;
const first = firstLine.split`,`;
const second = secondLine.split`,`;
const wires = {};
[first,second].forEach(input => {
	const currentWire = {};
	input.forEach(coord => {
		const [length] = coord.match(/\d+/);
		const directionIndex = +/U|D/.test(coord[0]);
		const sign = /U|R/.test(coord[0]) || -1;
		[...Array(+length)].map((_,j)=>{
			fc[directionIndex] += +sign;
			fc[2] += 1;
			const wiresIndex = `${fc[0]}_${fc[1]}`;
			wires[wiresIndex] = wires[wiresIndex] || [];
			if (!currentWire[wiresIndex]) {
				wires[wiresIndex].push(fc[2]);
				currentWire[wiresIndex] = fc[2];
			}
		});
	}, fc=[0,0,0]);
});
const crossesKeys=Object.keys(wires).filter(key=>wires[key].length>1);
// Part 1
crossesKeys.map(key=>(x=key.split`_`,Math.abs(x[0])+Math.abs(x[1]))).sort((x,y)=>x-y)[0];
// Part 2
crossesKeys.map(key=>wires[key][0]- -wires[key][1]).sort((x,y)=>x-y)[0];