Move Zeroes · Code

Problem

Given an integer array nums, write a function to rearrange the array by moving all zeros to the end while keeping the order of non-zero elements unchanged. Perform this operation in-place without creating a copy of the array.

Input:

nums = [2,0,4,0,9]

Output:

[2,4,9,0,0]

Explanation

We can solve this problem by keeping a pointer i that iterates through the array and another pointer nextNonZero that points to the position where the next non-zero element should be placed. We can then swap the elements at i and nextNonZero if the element at i is non-zero. This way, we can maintain the relative order of the non-zero elements while moving all the zeroes to the end of the array.

Solution

def moveZeroes(nums):
    nextNonZero = 0
    for i in range(len(nums)):
        if nums[i] != 0:
            nums[nextNonZero], nums[i] = nums[i], nums[nextNonZero]
            nextNonZero += 1

public static void moveZeroes(int[] nums) {
    int nextNonZero = 0;
    for (int i = 0; i < nums.length; i++) {
        if (nums[i] != 0) {
            int temp = nums[nextNonZero];
            nums[nextNonZero] = nums[i];
            nums[i] = temp;
            nextNonZero++;
        }
    }
}

func moveZeroes(nums []int) {
    nextNonZero := 0
    for i := 0; i < len(nums); i++ {
        if nums[i] != 0 {
            nums[nextNonZero], nums[i] = nums[i], nums[nextNonZero]
            nextNonZero++
        }
    }
}

function moveZeroes(nums: number[]): void {
    let nextNonZero: number = 0;
    for (let i: number = 0; i < nums.length; i++) {
        if (nums[i] !== 0) {
            [nums[nextNonZero], nums[i]] = [nums[i], nums[nextNonZero]];
            nextNonZero++;
        }
    }
}