[Destructuring Assignment] #JavaScript #Array #

destructuring-assignment.js

/**
 * Function: moveZeros
 * Description: This function moves all zeros in an array to the end of the array, while 
 * preserving the order of the other elements. Without creating a new Array.
 * Note: this uses a common two-pointer method, is O(n) and does not create a new array
 * @param {Array} nums - The input array.
 * @return {Array} The modified input array.
 */
const moveZeros = (nums) => {
    let left = 0
    let right = 0
    while (right < nums.length) {
        // If the current element is not zero, 
        // swap it with the element at the 'left' index
        if (nums[right] !== 0) {
            // destructuring assignment with swap.
            // Doing this way avoids allocation three variables
            [nums[left], nums[right]] = [nums[right],nums[left]]
            left++;
        }
        right++;
    }
    return nums
}


console.log( moveZeros([0,1,2,3]) )
console.log( moveZeros([1,2,0,3,4]) )
console.log( moveZeros([1,2,3,4,0]) )
console.log( moveZeros([1,0,0,4]) )
console.log( moveZeros([0,2,3,0]) )
console.log( moveZeros([0]) )
console.log( moveZeros([1]) )
console.log( moveZeros([]) )
/**
 * [ 1, 2, 3, 0 ]
 * [ 1, 2, 3, 4, 0 ]
 * [ 1, 2, 3, 4, 0 ]
 * [ 1, 4, 0, 0 ]
 * [ 2, 3, 0, 0 ]
 * [ 0 ]
 * [ 1 ]
 * []
 */