#!/usr/bin/env python3 import re lines = (x.strip() for x in open("input.txt")) points = {} for line in lines: [x1, y1, x2, y2] = list(map(int, re.match(r"(\d+),(\d+) -> (\d+),(\d+)", line).groups())) if x1 == x2: for y in range(min(y1, y2), max(y1, y2)+1): points[(x1, y)] = points.get((x1, y), 0) + 1 elif y1 == y2: for x in range(min(x1, x2), max(x1, x2)+1): points[(x, y1)] = points.get((x, y1), 0) + 1 print(sum(1 if val >= 2 else 0 for val in points.values()))