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public class Test01 {
public static void main(String[] args) { TreeSet ts = new TreeSet(); ts.add(\ ts.add(\ ts.add(\ ts.add(\ }
Iterator it = ts.iterator(); while(it.hasNext()) {
System.out.println(it.next()); }
}
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import java.util.ArrayList; public class Test02 { }
public static void main(String[] args) { }
ArrayList list = new ArrayList(); list.add(\ list.add(\ list.add(\ }
for (String obj : list) {
System.out.println(obj);
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import java.util.*; public class Test03 { }
public static void main(String[] args) { }
ArrayList list = new ArrayList(); list.add(\list.add(\list.add(\
ListIterator it = list.listIterator(); while(it.hasPrevious()) { }
Object obj = it.previous(); System.out.print(obj+\
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import java.util.*; import java.util.Map.*;
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public class Test04 { }
public static void main(String[] args) { }
Map map = new HashMap(); map.put(1, \map.put(2, \map.put(3,\
Set keySet = map.keySet(); Iterator it = keySet.iterator(); while (it.hasNext()) { }
Object key = it.next(); System.out.println(key); map.remove(key);
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import java.io.*;
public static void main(String args[])throws Exception{
int a=4;
BufferedReader br=new BufferedReader(new (System.in)); System.out.println(\ÇëÊäÈëÒ»¸öÊý×Ö\String input= ; int b=Integer.parseInt(input);
public class Test1 {
if(b>a){
int sum=b/a;
System.out.println(sum); }else{
System.out.println(\ÊäÈë´íÎó\ } } }
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import java.io.*; class Test2 {
public static void main(String[] args) {
String file1, file2; int ch = 0;
file1 = \file2 = \try {
FileInputStream fis = new ;
fos=new FileOutputStream(file2); int size= ;
System.out.println(\×Ö½ÚÓÐЧÊý¡¢\ while ((ch = fis.read()) != -1) { }
fis.close(); fos.close();
System.out.write(ch); fos.write(ch);