java 全排列 递归实现

package com.syj.csdn;

import java.util.ArrayList;

import java.util.Arrays;
import java.util.List;

/**
* <p>
* Title:全排列算法
* </p>
*
*/
public class FullSort {

//将NUM设置为待排列数组的长度即实现全排列

private static
int NUM = 3;

/**
* 递归算法：将数据分为两部分，递归将数据从左侧移右侧实现全排列
*
* @param datas
* @param target
*/
private static
void sort(List datas, List target) {

if (target.size() == NUM) {

for (Object obj : target)

System.out.print(obj);
System.out.println();
return;
}
for (int i =
0; i < datas.size(); i++) {
List newDatas = new ArrayList(datas);

List newTarget = new ArrayList(target);

newTarget.add(newDatas.get(i));
newDatas.remove(i);
sort(newDatas, newTarget);
}
}

public static
void main(String[] args) {
String[] datas = new String[] {
"a", "b",
"c", "d" };

sort(Arrays.asList(datas), new ArrayList());

}

}