forked from shuang790228/GeekTime-MathLecture-JavaCode
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathLesson8_1.java
More file actions
42 lines (29 loc) · 1.22 KB
/
Lesson8_1.java
File metadata and controls
42 lines (29 loc) · 1.22 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
import java.util.ArrayList;
import java.util.Arrays;
public class Lesson8_1 {
/**
* @Description: 使用函数的递归（嵌套）调用，找出所有可能的队伍组合
* @param teams-目前还剩多少队伍没有参与组合，result-保存当前已经组合的队伍
* @return void
*/
public static void combine(ArrayList<String> teams, ArrayList<String> result, int m) {
// 挑选完了m个元素，输出结果
if (result.size() == m) {
System.out.println(result);
return;
}
for (int i = 0; i < teams.size(); i++) {
// 从剩下的队伍中，选择一队，加入结果
ArrayList<String> newResult = (ArrayList<String>)(result.clone());
newResult.add(teams.get(i));
// 只考虑当前选择之后的所有队伍
ArrayList<String> rest_teams = new ArrayList<String>(teams.subList(i + 1, teams.size()));
// 递归调用，对于剩余的队伍继续生成组合
combine(rest_teams, newResult, m);
}
}
public static void main(String[] args) {
ArrayList<String> teams = new ArrayList<String>(Arrays.asList("t1", "t2", "t3"));
Lesson8_1.combine(teams, new ArrayList<String>(), 2);
}
}