aoc day 3

www/statics/aoc/2019/03_solution-1.ts

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+namespace AdventOfCode2019_03_1
+{
+	const DAY     = 3;
+	const PROBLEM = 1;
+
+	class Mov
+	{
+		dir: string;
+		len: number;
+
+		constructor(v: string) { this.dir = v[0]; this.len = parseInt(v.substr(1)); }
+	}
+
+	class Pos
+	{
+		x: number;
+		y: number;
+
+		constructor(x: number, y: number) { this.x = x; this.y = y; }
+
+		manhatten() {
+			return Math.abs(this.x)+Math.abs(this.y);
+		}
+
+		ident() { return this.x*10000+this.y; }
+
+		static manhattenCompare(a: Pos, b: Pos): number
+		{
+			const aa = a.manhatten();
+			const bb = b.manhatten();
+			if (aa>bb) return +1;
+			if (aa<bb) return -1;
+			return 0;
+		}
+	}
+
+	function getPath(movs: Mov[])
+	{
+		let r = [];
+
+		let x = 0;
+		let y = 0;
+
+		for(let mov of movs)
+		{
+			for(let i=0; i < mov.len; i++)
+			{
+				if (mov.dir == "U")y++;
+				if (mov.dir == "R")x++;
+				if (mov.dir == "D")y--;
+				if (mov.dir == "L")x--;
+				r.push(new Pos(x,y))
+			}
+		}
+
+		return r;
+	}
+
+	export async function run()
+	{
+		let input = await AdventOfCode.getInput(DAY);
+		if (input == null) return;
+
+		const xin = input
+			.split(new RegExp('\r?\n'))
+			.filter(p => p.trim().length > 0)
+			.map(p => p.split(",").map(q => new Mov(q)) )
+			.map(p => getPath(p));
+
+		const path1 = xin[0];
+		const path2 = xin[1];
+
+		let intersections = [];
+
+		let p1hash: { [_:number]:Pos } = {};   
+
+		for(let p1 of path1) p1hash[p1.ident()] = p1;
+
+		for(let p2 of path2)
+		{
+			if (p2.ident() in p1hash) intersections.push(p2);
+		}
+
+		intersections.sort((a,b) => Pos.manhattenCompare(a, b))
+
+        AdventOfCode.output(DAY, PROBLEM, intersections[0].manhatten().toString());
+	}
+}