2665-Counter-II.js

/**
 * Write a function createCounter. It should accept an initial integer init.
 * It should return an object with three functions.
 *
 * The three functions are:
 *
 * increment() increases the current value by 1 and then returns it.
 * decrement() reduces the current value by 1 and then returns it.
 * reset() sets the current value to init and then returns it.
 *
 * Example 1:
 *
 * Input: init = 5, calls = ["increment","reset","decrement"]
 * Output: [6,5,4]
 * Explanation:
 * const counter = createCounter(5);
 * counter.increment(); // 6
 * counter.reset(); // 5
 * counter.decrement(); // 4
 *
 * Example 2:
 *
 * Input: init = 0, calls = ["increment","increment","decrement","reset","reset"]
 * Output: [1,2,1,0,0]
 * Explanation:
 * const counter = createCounter(0);
 * counter.increment(); // 1
 * counter.increment(); // 2
 * counter.decrement(); // 1
 * counter.reset(); // 0
 * counter.reset(); // 0
 *
 */

/**
 * @param {integer} init
 * @return { increment: Function, decrement: Function, reset: Function }
 */
var createCounter = function (init) {
  let count = init;

  return {
    increment: function () {
      return ++count;
    },
    decrement: function () {
      return --count;
    },
    reset: function () {
      count = init;
      return count;
    },
  };
};

/**
 * const counter = createCounter(5)
 * counter.increment(); // 6
 * counter.reset(); // 5
 * counter.decrement(); // 4
 */