coding-challenges/leetcode/allow-one-function-call.js at main · raul-sauco/coding-challenges

41 lines (38 loc) · 1.02 KB

// 2666. Allow One Function Call

// 🟢 Easy

// https://leetcode.com/problems/allow-one-function-call/

// Tags: Javascript

// Preserve one boolean value with internal state that determines whether the

// funcion has been called already once, when called, if it is the first call,

// return the result of calling fn with the given arguments, if it is not the

// first call, do not return anything, which is the same as explicitly

// returning undefined. Use `apply` to pass the caller's context to fn.

// Time complexity: O(1)

// Space complexity: O(1)

// Runtime 68 ms Beats 8.32%

// Memory 41.6 MB Beats 90.70%

/**

* @param {Function} fn

* @return {Function}

var once = function (fn) {

let called = false;

return function (...args) {

if (!called) {

called = true;

// Preserve the caller's context.

return fn.apply(this, args);

}

};

/**

* let fn = (a,b,c) => (a + b + c)

* let onceFn = once(fn)

* onceFn(1,2,3); // 6

* onceFn(2,3,6); // returns undefined without calling fn

Provide feedback