Java for LeetCode 075 Sort Colors

Given an array with n objects colored red, white or blue, sort them 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.

解题思路：

快排速度太慢，不如直接用两个指针进行标记，0放到left左边2放到right右边，JAVA实现如下：

    public void sortColors(int[] nums) {
        int left = 0, right = nums.length - 1;
		for (int i = 0; i <= right;) {
			if (nums[i] == 0 && i > left) {
				int temp = nums[i];
				nums[i] = nums[left];
				nums[left] = temp;
				left++;
			} else if (nums[i] == 2 && i < right) {
				int temp = nums[i];
				nums[i] = nums[right];
				nums[right] = temp;
				right--;
			} else
				i++;
		}
    }

Java for LeetCode 075 Sort Colors

原文：http://www.cnblogs.com/tonyluis/p/4509920.html