#!/usr/local/bin/node // // See ../README.md // // // Run as: node ch-2.js < input-file // function dist (x1, y1, x2, y2) { return (x1 - x2) ** 2 + (y1 - y2) ** 2 } require ('readline') . createInterface ({input: process . stdin}) . on ('line', line => { let [x1, y1, x2, y2, x3, y3, x4, y4] = line . split (/ +/) . map (_ => +_) console . log (dist (x1, y1, x2, y2) == dist (x2, y2, x3, y3) && dist (x2, y2, x3, y3) == dist (x3, y3, x4, y4) && dist (x3, y3, x4, y4) == dist (x4, y4, x1, y1) && dist (x1, y1, x3, y3) == dist (x2, y2, x4, y4) ? 1 : 0) })