Unique Paths

My Solution

JavaScript

var uniquePaths = (function (m, n) {
  let cache = {};

  const func = function (m, n) {
    if (m === 1 && n === 1) return 1;
    if (m === 0 || n === 0) return 0;

    const key1 = `${m},${n}`;
    const key2 = `${n},${m}`;

    if (key1 in cache || key2 in cache) {
      result = cache[key1];
    } else {
      result = func(m - 1, n) + func(m, n - 1);
      cache[key1] = result;
      cache[key2] = result;
    }

    return result;
  };

  return func;
})();