283. Move Zeroes

JIAKAOBO

LeetCode

感谢赞助!

• ㊗️
• 大家
• offer
• 多多！

Problem

Given an array nums, write a function to move all 0’s to the end of it while maintaining the relative order of the non-zero elements.

Example:

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

Note:

You must do this in-place without making a copy of the array. Minimize the total number of operations.

Code

class Solution {
    public void moveZeroes(int[] nums) {
        int p = 0;
        for(int i = 0; i < nums.length; i++){
            if (nums[i] != 0){
                nums[p++] = nums[i];
            }
        }
        
        for(int i = p; i < nums.length; i++){
            nums[i] = 0;
        }
    }
}

class Solution:
    def moveZeroes(self, nums: List[int]) -> None:
        """
        Do not return anything, modify nums in-place instead.
        """
        index = 0
        for i in range(0, len(nums)):
            if nums[i] != 0:
                nums[index] = nums[i]
                index += 1

        for i in range(index, len(nums)):
            nums[i] = 0

当有很多 0 的时候，下面的解法更好

class Solution:
    def moveZeroes(self, nums: List[int]) -> None:
        """
        Do not return anything, modify nums in-place instead.
        """
        index = 0
        for i in range(0, len(nums)):
            if nums[i] != 0:
                if i != index:
                    nums[index] = nums[i]
                    nums[i] = 0
                index += 1