Problem

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

Constraints:

-1000 <= init <= 1000 0 <= calls.length <= 1000 calls[i] is one of “increment”, “decrement” and ”reset”

Pre analysis

Simple closure JS implementation