Problem

Given a positive integer millis, write an asynchronous function that sleeps for millis milliseconds. It can resolve any value.

Example 1:

Input: millis = 100 Output: 100 Explanation: It should return a promise that resolves after 100ms. let t = Date.now(); sleep(100).then(() => { console.log(Date.now() - t); // 100 });

Example 2:

Input: millis = 200 Output: 200 Explanation: It should return a promise that resolves after 200ms.

Constraints:

1 <= millis <= 1000

Pre analysis

Will use setTimeout to resolve promise after given time.