集合練習問題

package Prac2;

import java.util.*;

public class Demo1 {
public static void main(String[] args) {
    Set set = new HashSet();
    while (set.size() < 7) {
        set.add((int) (Math.random() * 25 +1));
    }
    for (Integer temp : set)
        System.out.print(temp + "\t");

}

}

题目二：将26个字母随机放入TreeSet集合中

代码实现

package jihe;
import java.util.TreeSet;

public class Demo1 {
    public static class str {
        public static void main(String[] args) {
            TreeSet set=new TreeSet();
            Character[]data=new Character[26];
            for (int i = 0; i <26 ; i++) {
                data[i]=(char)('A'+i);
            }

           while(set.size()<26){
               set.add(data[((int)(Math.random()*26))]);
           }
            System.out.println(set.size());
            for(Object ojbk:set){
                System.out.println(ojbk);
            }
        }
    }
}