2725-interval-cancellation

2725. Interval Cancellation (Easy) (https://leetcode.com/problems/interval-cancellation/)

Given a function fn, an array of arguments args, and an interval time t, return a cancel function cancelFn. After a delay of cancelTimeMs, the returned cancel function cancelFn will be invoked: setTimeout(cancelFn, cancelTimeMs) The function fn should be called with args immediately and then called again every t milliseconds until cancelFn is called at cancelTimeMs ms. Constraints: - fn is a function - args is a valid JSON array - 1 <= args.length <= 10 - 30 <= t <= 100 - 10 <= cancelTimeMs <= 500

type JSONValue = null | boolean | number | string | JSONValue[] | { [key: string]: JSONValue }
type Fn = (...args: JSONValue[]) => void
 
function cancellable(fn: Fn, args: JSONValue[], t: number): Function {
  fn(...args)
  const timeoutId = setInterval(() => fn(...args), t)
  return () => clearInterval(timeoutId)
}
 
// Local check
const result: { time: number, returned: JSONValue }[] = []
const fn = (...values: JSONValue[]) => Number(values[0]) * 2
const args: JSONValue[] = [4]
const t = 35
const cancelTimeMs = 190
const start = performance.now()
 
function log(...argsArr: JSONValue[]) {
  const diff = Math.floor(performance.now() - start)
  result.push({ time: diff, returned: fn(...argsArr) })
}
 
const cancelFn = cancellable(log, args, t)
setTimeout(cancelFn, cancelTimeMs)
setTimeout(() => console.log(result), cancelTimeMs + t)

Example 1:
 
    Input: fn = (x) => x * 2, args = [4], t = 35
    Output:
    [
      { "time": 0, "returned": 8 },
      { "time": 35, "returned": 8 },
      { "time": 70, "returned": 8 },
      { "time": 105, "returned": 8 },
      { "time": 140, "returned": 8 },
      { "time": 175, "returned": 8 }
    ]
    Explanation:
    const cancelTimeMs = 190;
    const cancelFn = cancellable((x) => x * 2, [4], 35);
    setTimeout(cancelFn, cancelTimeMs);
 
    Every 35ms, fn(4) is called. Until t=190ms, then it is cancelled.
    1st fn call is at 0ms. fn(4) returns 8.
    2nd fn call is at 35ms. fn(4) returns 8.
    3rd fn call is at 70ms. fn(4) returns 8.
    4th fn call is at 105ms. fn(4) returns 8.
    5th fn call is at 140ms. fn(4) returns 8.
    6th fn call is at 175ms. fn(4) returns 8.
    Cancelled at 190ms.
 
  Example 2:
 
<!-- [[leetcode/untagged]] [[leetcode/untagged/2724-sort-by]] [[leetcode/untagged/2726-calculator-with-method-chaining]] -->
 
    Input: fn = (x1, x2) => (x1 * x2), args = [2, 5], t = 30
    Output:
    [
      { "time": 0, "returned": 10 },
      { "time": 30, "returned": 10 },
      { "time": 60, "returned": 10 },
      { "time": 90, "returned": 10 },
      { "time": 120, "returned": 10 },
      { "time": 150, "returned": 10 }
    ]
    Explanation:
    const cancelTimeMs = 165;
    const cancelFn = cancellable((x1, x2) => (x1 * x2), [2, 5], 30);
    setTimeout(cancelFn, cancelTimeMs);
 
    Every 30ms, fn(2, 5) is called. Until t=165ms, then it is cancelled.
    1st fn call is at 0ms.
    2nd fn call is at 30ms.
    3rd fn call is at 60ms.
    4th fn call is at 90ms.
    5th fn call is at 120ms.
    6th fn call is at 150ms.
    Cancelled at 165ms.
 
  Example 3:
 
    Input: fn = (x1, x2, x3) => (x1 + x2 + x3), args = [5, 1, 3], t = 50
    Output:
    [
      { "time": 0, "returned": 9 },
      { "time": 50, "returned": 9 },
      { "time": 100, "returned": 9 },
      { "time": 150, "returned": 9 }
    ]
    Explanation:
    const cancelTimeMs = 180;
    const cancelFn = cancellable((x1, x2, x3) => (x1 + x2 + x3), [5, 1, 3], 50);
    setTimeout(cancelFn, cancelTimeMs);
 
    Every 50ms, fn(5, 1, 3) is called. Until t=180ms, then it is cancelled.
    1st fn call is at 0ms.
    2nd fn call is at 50ms.
    3rd fn call is at 100ms.
    4th fn call is at 150ms.
    Cancelled at 180ms.