LeetCode Logo
Problem List
0

avatar
Premium
Debugging...
Debugging...







Run
Description
Editorial
Editorial
Solutions
Solutions
Submissions
Submissions


Code
Testcase
Test Result
Test Result
2715. Timeout Cancellation
Easy
Companies
Given a function fn, an array of arguments args, and a timeout t in milliseconds, return a cancel function cancelFn.

After a delay of cancelTimeMs, the returned cancel function cancelFn will be invoked.

setTimeout(cancelFn, cancelTimeMs)
Initially, the execution of the function fn should be delayed by t milliseconds.

If, before the delay of t milliseconds, the function cancelFn is invoked, it should cancel the delayed execution of fn. Otherwise, if cancelFn is not invoked within the specified delay t, fn should be executed with the provided args as arguments.

 

Example 1:

Input: fn = (x) => x * 5, args = [2], t = 20
Output: [{"time": 20, "returned": 10}]
Explanation: 
const cancelTimeMs = 50;
const cancelFn = cancellable((x) => x * 5, [2], 20);
setTimeout(cancelFn, cancelTimeMs);

The cancellation was scheduled to occur after a delay of cancelTimeMs (50ms), which happened after the execution of fn(2) at 20ms.
Example 2:

Input: fn = (x) => x**2, args = [2], t = 100
Output: []
Explanation: 
const cancelTimeMs = 50;
const cancelFn = cancellable((x) => x**2, [2], 100);
setTimeout(cancelFn, cancelTimeMs);

The cancellation was scheduled to occur after a delay of cancelTimeMs (50ms), which happened before the execution of fn(2) at 100ms, resulting in fn(2) never being called.
Example 3:

Input: fn = (x1, x2) => x1 * x2, args = [2,4], t = 30
Output: [{"time": 30, "returned": 8}]
Explanation: 
const cancelTimeMs = 100;
const cancelFn = cancellable((x1, x2) => x1 * x2, [2,4], 30);
setTimeout(cancelFn, cancelTimeMs);

The cancellation was scheduled to occur after a delay of cancelTimeMs (100ms), which happened after the execution of fn(2,4) at 30ms.
 

Constraints:

fn is a function
args is a valid JSON array
1 <= args.length <= 10
20 <= t <= 1000
10 <= cancelTimeMs <= 1000
Seen this question in a real interview before?
1/5
Yes
No
Accepted
56.4K
Submissions
63.5K
Acceptance Rate
88.8%
Companies
Discussion (56)

Choose a type



Copyright ©️ 2024 LeetCode All rights reserved

241


56



JavaScript
Auto





1234567891011121314151617
/**
 * @param {Function} fn
 * @param {Array} args
 * @param {number} t
 * @return {Function}
 */
var cancellable = function(fn, args, t) {
    
};


Saved
Case 1
Case 2
Case 3

fn =
(x) => x * 5
args =
[2]
t =
20
cancelTimeMs =
50
1
(x) => x * 5
[2]
20
50
(x) => x**2
[2]
100
50
(x1, x2) => x1 * x2
[2,4]


Tag
/**
 * @param {Function} fn
 * @param {Array} args
 * @param {number} t
 * @return {Function}
 */
var cancellable = function(fn, args, t) {
    
};

/**
 *  const result = [];
 *
 *  const fn = (x) => x * 5;
 *  const args = [2], t = 20, cancelTimeMs = 50;
 *
 *  const start = performance.now();
 *
 *  const log = (...argsArr) => {
 *      const diff = Math.floor(performance.now() - start);
 *      result.push({"time": diff, "returned": fn(...argsArr)});
 *  }
 *       
 *  const cancel = cancellable(log, args, t);
 *
 *  const maxT = Math.max(t, cancelTimeMs);
 *           
 *  setTimeout(cancel, cancelTimeMs);
 *
 *  setTimeout(() => {
 *      console.log(result); // [{"time":20,"returned":10}]
 *  }, maxT + 15)
 */