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Sort colors

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Linkage

https://leetcode.com/problems/sort-colors/description/

Idea

0……0 1……1 x1 x2 …. xm 2…..2

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​ left i right

Code

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class Solution {
    public void sortColors(int[] nums) {
        //[left, right] is 1
        
        int left=0, right=nums.length - 1;
        int i = 0;
        while(i <= right) {
            if(nums[i]==0) {
                swap(nums, i++, left++);
                continue;
            }if(nums[i]==1) {
                i++;
                continue;
            } 
            if(nums[i]==2) {
                swap(nums, i, right--);
                continue;
            }
                
        }
    }
    
    public void swap(int[] array, int left, int right) {
        int temp = array[left];
        array[left] = array[right];
        array[right] = temp;
    }
}