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1 public class Exercise21_06 { 2 public static void main(String[] args){ 3 int key; 4 // 创建一个散列映射 5 HashMap<Integer, Integer> hashMap = new HashMap<>(); 6 // 创建一个Scanner对象 7 Scanner input = new Scanner(System.in); 8 System.out.println("请输入整数"); 9 10 do{ 11 key = input.nextInt(); 12 if(hashMap.containsKey(key)){ 13 hashMap.put(key, hashMap.get(key) + 1); 14 }else{ 15 hashMap.put(key, 1); 16 } 17 }while(key != 0); 18 19 TreeSet<Integer> treeSet = new TreeSet<>(hashMap.values()); 20 for(int k: hashMap.keySet()){ 21 if(hashMap.get(k)==treeSet.last()){ 22 System.out.println(k + "出现的次数最高,共计" + treeSet.last() + "次"); 23 } 24 } 25 } 26 }
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public class WordOccurrence implements Comparable{ String word; int count; public WordOccurrence(String word, int count){ this.word = word; this.count = count; } @Override public int compareTo(Object o) { WordOccurrence w = (WordOccurrence)o; return this.count - w.count; } }
public class CountOccurrenceOfWords { public static void main(String[] args){ // 创建一个String文本 String text = "Good Morning. Have a good class." + "Have a good visit. Have fun!"; // 创建一个树形映射 TreeMap<String, Integer> treeMap = new TreeMap<>(); // 提取文本中的单词 String[] words = text.split("[\s+\p{P}]"); for(String s: words){ if(s.length() > 0){ if(!treeMap.containsKey(s)){ treeMap.put(s.toLowerCase(), 1); }else{ treeMap.put(s.toLowerCase(), treeMap.get(s) + 1); } } } ArrayList<WordOccurrence> aList = new ArrayList<>(); for(String k: treeMap.keySet()){ WordOccurrence wo = new WordOccurrence(k, treeMap.get(k)); aList.add(wo); } Collections.sort(aList, new Comparator(){ public int compare(Object o1, Object o2){ WordOccurrence wo1 = (WordOccurrence)o1; WordOccurrence wo2 = (WordOccurrence)o2; return wo1.compareTo(wo2); } }); for(WordOccurrence w: aList){ System.out.println(w.word + " " + w.count); } } }
如果将WordOccurrence实例放入树形集,最终只会输出数量不重复的单词!
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public class Exercise30_01 extends Application{ static TextArea tf = new TextArea(); public static void main(String[] args){ Application.launch(args); } @Override public void start(Stage stage){ tf.setMinWidth(700); tf.setWrapText(true); Scene scene = new Scene(tf, 700, 300); stage.setScene(scene); stage.setTitle("Exercise30_01"); stage.show(); Runnable printA = new printChar(tf, "a", 100); Runnable printB = new printChar(tf, "b", 100); Runnable print100 = new printNum(tf, 100); Thread thread1 = new Thread(printA); Thread thread2 = new Thread(printB); Thread thread3 = new Thread(print100); thread1.start(); thread2.start(); thread3.start(); } } class printChar implements Runnable{ TextArea tf; String charToPrint; int times; public printChar(TextArea tf, String c, int t){ this.tf = tf; charToPrint = c; times = t; } @Override public void run() { Platform.runLater(new Runnable() { public void run() { for(int i = 0; i < times; i++){ tf.appendText(" " + charToPrint); } } }); } } class printNum implements Runnable{ TextArea tf; int lastNum; public printNum(TextArea tf,int last){ lastNum = last; this.tf = tf; } @Override public void run() { Platform.runLater(new Runnable() { public void run() { for(int i = 1; i <= lastNum; i++){ final int j = i; tf.appendText(Integer.toString(j) + " "); } } }); } }
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public class FlagRisingAnimation extends Application{ static ImageView imageView = new ImageView("file:D:\China.jpg"); @Override public void start(Stage stage) throws Exception { Pane pane = new Pane(); pane.getChildren().add(imageView); Scene scene = new Scene(pane,1000,600); stage.setTitle("Exercise30.3"); stage.setScene(scene); stage.show(); Runnable rising1 = new Rising(); Thread thread1 = new Thread(rising1); thread1.start(); } static class Rising implements Runnable{ @Override public void run() { PathTransition pt = new PathTransition(Duration.millis(10000),new Line(400,200,400,0),imageView); pt.setCycleCount(5); pt.play(); } } public static void main(String[] args){ Application.launch(args); } } 用线程模拟更快!