typescript aoc day 25 solution

day25.ts

const input = await Deno.readTextFile("./input.txt");

const lines = input.split("\n");

const dv = {
  "2": 2,
  "1": 1,
  "0": 0,
  "-": -1, // === -1
  "=": -2, // === -2
};

const convertB5ToNum = (number: string): number => {
  let result = 0;
  for (let i = 0; i < number.length; i++) {
    const digit = number[i];
    const digitValue = dv[digit as keyof typeof dv];
    result += digitValue * Math.pow(5, number.length - i - 1);
  }
  return result;
};

function convertNumToB5(n: number): string {
  if (n === 0) return "";
  if (n % 5 === 0) return convertNumToB5(Math.floor(n / 5)) + "0";
  if (n % 5 === 1) return convertNumToB5(Math.floor(n / 5)) + "1";
  if (n % 5 === 2) return convertNumToB5(Math.floor(n / 5)) + "2";
  if (n % 5 === 3) return convertNumToB5((n + 2) / 5) + "=";
  if (n % 5 === 4) return convertNumToB5((n + 1) / 5) + "-";

  throw new Error("should never hit here");
}

const nums = lines.map(convertB5ToNum);

const sum = nums.reduce((a, b) => a + b, 0);
console.log(sum);

const ans = convertNumToB5(sum);
console.log(ans);