import fs from "node:fs";

let data = fs.readFileSync("input", "utf8");

let lines = data
  .split("\n")
  .map(l => l.split("").filter(c => +c == c))
  .map(l => [l[0], l[l.length - 1]])
  .map(l => l.join(""))
  .map(n => Number(n))
  .reduce((acc, n) => acc + n);

console.log(lines);