LeetCode 283. Move Zeroes

283. Move Zeroes

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.

For example, given nums = [0, 1, 0, 3, 12], after calling your function, nums should be [1, 3, 12, 0, 0].

Note:

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

Credits:
Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases.

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【题目分析】

给定一个整数数组，把数组中非零元素都移动到数组的左半部分，要求非零元素的相对位置不变。

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【思路】

遍历数组，用一个指针记录发现非零元素后的插入位置，然后把数组的后半部分设置为0.

总结：虽然是一道很简单的题目，但是想写出优雅的代码还是有难度的。一定要美美美！

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【java代码】

public class Solution {
    public void moveZeroes(int[] nums) {
        if(nums == null || nums.length <= 1) return;
        
        int insertPos = 0;
        for(int num : nums) {
            if(num != 0) nums[insertPos++] = num;
        }
        
        while(insertPos < nums.length) {
            nums[insertPos++] = 0;
        }
    }
}