LeetCode-283. Move Zeroes

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问题描述

Given an integer array nums, move all 0‘s to the end of it while maintaining the relative order of the non-zero elements.

Note that you must do this in-place without making a copy of the array.

Example 1:

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Input: nums = [0,1,0,3,12]
Output: [1,3,12,0,0]

Constraints:

  • 1 <= nums.length <= 104
  • -231 <= nums[i] <= 231 - 1

解答

方法一：双指针
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/*
 * @Description: 283. Move Zeroes
 * @Author: libk
 * @Github: https://github.com/libk
 */
/**
 * @param {number[]} nums
 * @return {void} Do not return anything, modify nums in-place instead.
 */
const moveZeroes = function (nums) {
  let left = 0
  let right = 0

  while (right < nums.length) {
    if (nums[right]) {
      let temp = nums[right]
      nums[right] = nums[left]
      nums[left] = temp
      left++
    }
    right++
  }
}
方法二：双指针改进

既然要处理的数字是0，那就不必交换，直接覆盖，末尾补零即可

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/*
 * @Description: 283. Move Zeroes
 * @Author: libk
 * @Github: https://github.com/libk
 */
/**
 * @param {number[]} nums
 * @return {void} Do not return anything, modify nums in-place instead.
 */
const moveZeroes2 = function (nums) {
  let left = 0
  let right = 0

  while (right < nums.length) {
    if (nums[right]) {
      nums[left++] = nums[right]
    }
    right++
  }
  while (left < nums.length) {
    nums[left++] = 0
  }
}