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# Problem

Given an array with n objects colored red, white or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the order red, white and blue.

Here, we will use the integers 0, 1, and 2 to represent the color red, white, and blue respectively.

Note: You are not suppose to use the library’s sort function for this problem.

## example 1

 ``````1 2 `````` ``````Input: [2,0,2,1,1,0] Output: [0,0,1,1,2,2] ``````

Main idea is use two pointers: `end of zero sequence`, and `end of one sequene`.
Walk throw array and check if current element in zero – swap it with next element of `end of zero sequence`. If current element is one – swap in with next element of `end of one sequene`.
 `````` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 `````` ``````func sortColors(nums []int) { ez:=-1 eo:=-1 for idx:=range nums { if nums[idx] == 0 && ez != idx { ez++ nums[idx], nums[ez] = nums[ez], nums[idx] } if nums[idx] == 1 && eo != idx { if eo == -1 { eo = ez } eo++ nums[idx], nums[eo] = nums[eo], nums[idx] } } } ``````