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: ()=> ++count,
        decrement: ()=> --count,
        reset: ()=>count = init
    }
};

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