What are the differences between JavaScript's Array.shift() and Array.unshift() methods?
Richard W

TheArray.shift() andArray.unshift() methods in JavaScript are used to manipulate the elements at the beginning of an array. Here's a detailed explanation of their differences: 1.Array.shift(): - Theshift() method removes the first element from an array and returns that removed element. - It mutates the original array by modifying its length and shifting all other elements to a lower index. - If the array is empty,shift() returnsundefined. - Example usage:

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     const array = [1, 2, 3];
     const firstElement = array.shift();
     console.log(firstElement); // Output: 1
     console.log(array); // Output: [2, 3]

2.Array.unshift(): - Theunshift() method adds one or more elements to the beginning of an array and returns the new length of the array. - It mutates the original array by shifting existing elements to higher indices to make room for the new elements. - It can accept multiple arguments, and the order of the arguments determines the order of the new elements in the array. - Example usage:

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     const array = [2, 3];
     const newLength = array.unshift(1);
     console.log(newLength); // Output: 3
     console.log(array); // Output: [1, 2, 3]

Key differences: -shift() removes and returns the first element, whileunshift() adds elements to the beginning of the array and returns the new length. -shift() mutates the array by modifying its length and shifting remaining elements, whileunshift() mutates the array by shifting existing elements to make room for new elements. -shift() modifies the original array, whileunshift() modifies the original array and returns the new length. -shift() can returnundefined if the array is empty, whileunshift() always returns the new length of the array. It's important to consider these differences when deciding which method to use based on your specific requirements for manipulating arrays in JavaScript.

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