Advent of Code - Day 1

inverseCaptcha.re

let inverseCaptcha = (path) => {
  let arr =
    Node_fs.readFileSync(path, `utf8)
    |> Js.String.trim
    |> Js.String.split("");
  Js.Array.reducei(
    (acc, curr, idx) =>
      switch (idx == 0) {
      | true =>
        let firstValue = int_of_string(curr);
        let lastValue = int_of_string(arr[Js.Array.length(arr) - 1]);
        firstValue == lastValue ? acc + firstValue : acc;
      | _ =>
        let prevValue = int_of_string(arr[idx - 1]);
        let currValue = int_of_string(curr);
        prevValue == currValue ? acc + currValue : acc;
      },
    0,
    arr
  );
};

let result = inverseCaptcha("./src/inverse-captcha.txt");

Js.log(result);