public class Permutate {
/**
* 保存生成的排列组合内容
**/
public List<String> Permutation = new ArrayList<String>();
/**
* 递归的方式计算排列组合
*
* @param list 传入list.size()个集合
* @param preStr 上一步递归中生成的排列组合
* @return
*/
public void permutation(List<List<String>> list, String preStr) {
int size = list.size();
if (1 == size) {
for (int i = 0; i < list.get(0).size(); i++) {
Permutation.add(preStr + list.get(0).get(i));
}
} else {
List<String> permu = new ArrayList<String>(list.get(0));
List<List<String>> now = new ArrayList<List<String>>(list);
now.remove(0);
for (int i = 0; i < permu.size(); i++) {
permutation(now, preStr + permu.get(i));
}
}
}
public static void main(String[] args) throws Exception {
List<List<String>> list = new ArrayList<List<String>>();
List<String> SET1 = new ArrayList<String>();
SET1.add("黑");
SET1.add("白");
SET1.add("蓝");
List<String> SET2 = new ArrayList<String>();
SET2.add("大");
SET2.add("小");
List<String> SET3 = new ArrayList<String>();
SET3.add("长");
SET3.add("短");
list.add(SET1);
list.add(SET2);
list.add(SET3);
Permutate permutate = new Permutate();
permutate.permutation(list, "");
System.out.println(permutate.Permutation);
}
}
递归的方式计算排列组合
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转载自blog.csdn.net/qq_19897551/article/details/88292406
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