1.1 Sort Colors 单词遍历 给0,1,2排序 leetcode

本文介绍了一种不使用库排序函数的颜色排序算法。该算法通过遍历数组中的0、1、2并将其按顺序排列来实现红、白、蓝三色排序。文章提供了一个一程算法示例,使用常数空间完成排序。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

1.1      Sort Colors  单词遍历 给0,1,2排序

Given an array with n objectscolored red, white or blue, sort them so that objects of the same color areadjacent, with the colors in the order red, white and blue.

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

Note:
You are not suppose to use thelibrary's sort function for this problem.

Follow up:
A rather straight forwardsolution is a two-pass algorithm using counting sort.
First, iterate the arraycounting number of 0's, 1's, and 2's, then overwrite array with total number of0's, then 1's and followed by 2's.

Could you come up with an one-pass algorithmusing only constant space?



package Array;

import java.util.Arrays;

/**
 * @Title: SortColors.java
 * @Package Array
 * @Description: TODO
 * @author nutc
 * @date 2013-9-6 下午2:39:08
 * @version V1.0
 */
public class SortColors {

	public static void main(String args[]) {
		SortColors s = new SortColors();

		int[] a = { 2,0};
		s.sortColors(a);
		System.out.println(Arrays.toString(a));
	}

	public void sortColors(int[] A) {
		if (A == null)
			return;

		int i = 0, j = A.length - 1, k = 0;

		 while (i < A.length && A[i] == 0)
		 i++;
		 while (j >= 0 && A[j] == 2)
		 j--;
		k = i;
		while (k <= j && i <= j) {

			if (A[k] == 0) {
				if (k > i) {
					int temp = A[i];
					A[i] = A[k];
					A[k] = temp;
					i++;
				}else{
					k++;
				}
			} else if (A[k] == 2) {
				int temp = A[j];
				A[j] = A[k];
				A[k] = temp;
				j--;
			} else {
				k++;
			}
		}

	}

}



评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值