leetcode 27:移除元素

https://leetcode.cn/problems/remove-element/

class Solution {
    public int removeElement(int[] nums, int val) {
        int count=0;
        int[] index=new int[100];
        for(int i=0;i<nums.length;i++){
            if(nums[i]==val){
                count++;
                index[count]=i;
            }
        }
        int count1=count;
        for(int i=nums.length-count;i<nums.length;i++){
            if(nums[i]==val){
                count1--;
            }
        }
        for(int i=nums.length-count;i<nums.length;i++){
           
            if(nums[i]!=val){
                
                nums[index[count1--]]=nums[i];
                nums[i]=val;
            
            } 
        }
        return nums.length-count;
    }
}
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等于快慢指针法

class Solution {
    public int removeElement(int[] nums, int val) {
        // 快慢指针
        int slowIndex = 0;
        for (int fastIndex = 0; fastIndex < nums.length; fastIndex++) {
            if (nums[fastIndex] != val) {
                nums[slowIndex] = nums[fastIndex];
                slowIndex++;
            }
        }
        return slowIndex;
    }
}
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