移动0到数组末尾

只移动0，其他顺序不变；必须在元素组进行操作

会改变原数组内的值类型

const moveZeroByReg = (arr = [1,0,2,0,3,0,4,0,5]) => {
    const reg = /0/g
    let str = arr.join('')
    const res = str.match(reg)
    str = str.replace(reg, '')
    str += res.join('')
    arr = str.split('')
    return arr
}

使用splice 时间复杂度O(n^2)

const removeZeroBySplice = (arr = [1,0,2,0,3,0,4,0,5]) => {
    const { length } = arr
    let zeroCount = 0
    for(let i = 0; i < length - zeroCount; i++ ){
        if(arr[i] === 0){
            arr.splice(i,1)
            arr.push(0)
            i--
            zeroCount++
        }
    }
    return arr
}

　　双指针

/**
 * @param {number[]} nums
 * @return {void} Do not return anything, modify nums in-place instead.
 */
const moveZeroes = (nums) => {
    let zeroIndex = nums.indexOf(0)
    if (zeroIndex === -1) return nums
    for (let i = 0; i < nums.length; i++) {
        const v = nums[i]
        if (v !== 0 && i > zeroIndex) {
            [nums[zeroIndex], nums[i]] = [nums[i], nums[zeroIndex]]
            zeroIndex++
        }
    }
    return nums
};