1function createCounter() {
2  let count = 0;
3  
4  const counter = {
5    increase() {
6      count++;
7    },
8    decrease() {
9      count--;
10    },
11    getCount: () => count
12  };
13  
14  Object.defineProperty(counter, 'count', {
15    get: () => count,
16    set(value) {
17      if (typeof value === 'number') {
18        count = value;
19      }
20    },
21    configurable: false
22  });
23  
24  return counter;
25}
26
27const counter1 = createCounter();
28const counter2 = createCounter();
29
30counter1.increase();
31counter2.count = 5;
32counter1.decrease();
33console.log(counter1.count, counter2.getCount());