2665. Counter II @LeetCode

 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"

Code:

1. /**
2. * @param {integer} init
3. * @return { increment: Function, decrement: Function, reset: Function }
4. */
5. var createCounter = function(init) {
6. // let reset = init;
7. let num = init;
8. return {
9. increment: function(){
10. return ++num;
11. },
12. 
    
13. decrement: function(){
14. return --num;
15. },
16. 
    
17. reset: function(){
18. return (num = init);
19. },
20. }
21. 
    
22. };
23. 
    
24. /**
25. * const counter = createCounter(5)
26. * counter.increment(); // 6
27. * counter.reset(); // 5
28. * counter.decrement(); // 4
29. */