const fs = require('fs/promises');

const sum = (arr) => arr.reduce((total, num) => total+num, 0);
const arrayOfLength = n => Array.from(Array(n).keys()).map(() => {});
                //minus
const keypress = async () => {
  process.stdin.setRawMode(true)
  return new Promise(resolve => process.stdin.once('data', data => {
    const byteArray = [...data]
    if (byteArray.length > 0 && byteArray[0] === 3) {
      console.log('^C')
      process.exit(1)
    }
    process.stdin.setRawMode(false)
    resolve()
  }))
}

const coords = ([x, y, z]) => `${x},${y},${z}`;

const main = async () => {
  const input = (await fs.readFile("./input.txt", 'utf8')).slice(0, -1).split("\n");
  const scan = input.reduce((s, point) => {
    s[point] = true;
    return s;
  }, {});


  const points = input.map(p => p.split(",").map(x => parseInt(x)));

  let surfaceCount = 0;

  for(const [x, y, z] of points) {
    const possibleNeighbors = [
      [0, 0, 1],
      [0, 0, -1],
      [0, 1, 0],
      [0, -1, 0],
      [1, 0, 0],
      [-1, 0, 0]
    ].map(([dx, dy, dz]) => ([x + dx, y + dy, z + dz]));

    for(const n of possibleNeighbors) {
      if(!scan[coords(n)]) {
        surfaceCount++
      }
    }
  }

  console.log("Answer: ", surfaceCount);

}

main();