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package arrays.file;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
i ......
package collection;
import java.util.*;
public class NewArrayList {
public static void main(String[] args) {
List<Student> students = new ArrayList<Student>();
for (int i = 0; i < 6; i++) {
students.add(new Student("Happy"+i,"male" ......
package collection;
import java.util.*;
public class NewSet {
public static void main(String[] args) {
Set<Student> students = new HashSet<Student>();
for (int i = 0; i < 6; i++) {
students.add(new Student("Happy"+i,"male"+i,20+i)) ......
package collection;
public class Student {
public Student() {}
public Student(String name, String sex, int age) {
this.name = name;
this.sex = sex;
this.age = age;
}
@Override
public String toString() {
......