在Java中使用递归对队列进行排序

huangapple
go评论102阅读模式
英文:

Sorting Queue in Java with recursion

问题

  1. import java.util.*;
  3. public class Source {
  4.     public static void main(String args[]) {
  5.         Queue<Integer> queue = new LinkedList<Integer>();
  6.         Scanner s = new Scanner(System.in);
  7.         int n = s.nextInt();
  8.         while (n-- > 0) 
  9.             queue.add(s.nextInt());
  10.         sort(queue);
  11.     }
  13.     static void FrontToLast(Queue<Integer> queue, int qsize) {
  15.         if (qsize <= 0) {
  16.             return; 
  17.         }
  18.         queue.add(queue.peek()); 
  19.         queue.remove(); 
  20.         FrontToLast(queue, qsize - 1); 
  21.     }
  24.     static void pushInQueue(Queue<Integer> queue, int temp, int qsize) {
  25.         if (queue.isEmpty() || qsize == 0)  
  26.         { 
  27.             queue.add(temp); 
  28.             return; 
  29.         }
  30.         else if (temp <= queue.peek()) 
  31.         { 
  32.             queue.add(temp);
  33.             FrontToLast(queue, qsize); 
  34.         }
  35.         else 
  36.         { 
  37.             queue.add(queue.peek()); 
  38.             queue.remove(); 
  39.             pushInQueue(queue, temp, qsize - 1); 
  40.         }
  41.     }
  42.     
  43.     static void sort(Queue<Integer> queue) {
  44.         if (queue.isEmpty()) {
  45.             return; 
  46.         }
  47.         int temp = queue.peek();
  48.         queue.remove(); 
  49.         sort(queue); 
  50.         pushInQueue(queue, temp, queue.size());
  51.           
  52.         while (!queue.isEmpty())  
  53.         { 
  54.             System.out.print(queue.peek() + " "); 
  55.             queue.remove();
  56.         }
  57.     }
  58. }
英文:

I am trying to sort a queue (in ascending order), using the recursion method. The input is entered by the user.
This one below is not giving me the correct output. For instance: 12. Elements: 6 12 3 4 5 1 7 8 10 9 11 2, result: 2 11 9 10 8 7 1 5 4 3 12 6, which is incorrect. I am trying to figure out which part is not correct. I do not want to change anything in the main method.

  1. import java.util.*;
  2. public class Source {
  3. public static void main(String args[]) {
  4. Queue&lt;Integer&gt; queue = new LinkedList&lt;Integer&gt;();
  5. Scanner s = new Scanner(System.in);
  6. int n = s.nextInt();
  7. while (n-- &gt; 0) 
  8. queue.add(s.nextInt());
  9. sort(queue);
  10. }
  11. static void FrontToLast(Queue&lt;Integer&gt; queue,int qsize) {
  12. if (qsize &lt;= 0) {
  13. return; 
  14. }
  15. queue.add(queue.peek()); 
  16. queue.remove(); 
  17. FrontToLast(queue, qsize - 1); 
  18. }
  19. static void pushInQueue(Queue&lt;Integer&gt; queue , int temp, int qsize) {
  20. if (queue.isEmpty() || qsize == 0)  
  21. { 
  22. queue.add(temp); 
  23. return; 
  24. }
  25. else if (temp &lt;= queue.peek()) 
  26. { 
  27. queue.add(temp);
  28. FrontToLast(queue, qsize); 
  29. }
  30. else 
  31. { 
  32. queue.add(queue.peek()); 
  33. queue.remove(); 
  34. pushInQueue(queue, temp, qsize - 1); 
  35. }
  36. }
  37. static void sort(Queue&lt;Integer&gt; queue) {
  38. if (queue.isEmpty()) {
  39. return; 
  40. }
  41. int temp = queue.peek();
  42. queue.remove(); 
  43. sort(queue); 
  44. pushInQueue(queue, temp, queue.size());
  45. while (!queue.isEmpty())  
  46. { 
  47. System.out.print(queue.peek() + &quot; &quot;); 
  48. queue.remove();
  49. }
  50. }
  51. }

答案1

得分: 1

  1. import java.util.LinkedList;
  2. import java.util.Queue;
  3. import java.util.Scanner;
  5. public class Source {
  6.     static Queue<Integer> queue = new LinkedList<Integer>(); // changed
  8.     public static void main(String args[]) {
  10.         Scanner s = new Scanner(System.in);
  11.         int n = s.nextInt();
  12.         while (n-- > 0)
  13.             queue.add(s.nextInt());
  14.         sort(queue);
  15.         System.out.println("Final Result: " + queue); // changed
  16.     }
  18.     static void FrontToLast(Queue<Integer> queue, int qsize) {
  20.         if (qsize <= 0) {
  21.             return;
  22.         }
  23.         queue.add(queue.peek());
  24.         queue.remove();
  25.         FrontToLast(queue, qsize - 1);
  26.     }
  28.     static void pushInQueue(Queue<Integer> queue, int temp, int qsize) {
  29.         if (queue.isEmpty() || qsize == 0) {
  30.             queue.add(temp);
  31.             return;
  32.         } else if (temp <= queue.peek()) {
  33.             queue.add(temp);
  34.             FrontToLast(queue, qsize);
  35.         } else {
  36.             queue.add(queue.peek());
  37.             queue.remove();
  38.             pushInQueue(queue, temp, qsize - 1);
  39.         }
  40.     }
  42.     static void sort(Queue<Integer> queue) {
  43.         if (queue.isEmpty()) {
  44.             return;
  45.         }
  46.         int temp = queue.peek();
  47.         queue.remove();
  48.         sort(queue);
  49.         pushInQueue(queue, temp, queue.size());
  51.         /*
  52.          * while (!queue.isEmpty()) { System.out.print(queue.peek() + " ");
  53.          * queue.remove(); }
  54.          */
  55.     }
  56. }
英文: 
  1. import java.util.LinkedList;

import java.util.Queue;
import java.util.Scanner;

public class Source {
static Queue<Integer> queue = new LinkedList<Integer>(); // changed

  1. public static void main(String args[]) {
  2. Scanner s = new Scanner(System.in);
  3. int n = s.nextInt();
  4. while (n-- &gt; 0)
  5. queue.add(s.nextInt());
  6. sort(queue);
  7. System.out.println(&quot;Final Result : &quot; + queue); // changed
  8. }
  9. static void FrontToLast(Queue&lt;Integer&gt; queue, int qsize) {
  10. if (qsize &lt;= 0) {
  11. return;
  12. }
  13. queue.add(queue.peek());
  14. queue.remove();
  15. FrontToLast(queue, qsize - 1);
  16. }
  17. static void pushInQueue(Queue&lt;Integer&gt; queue, int temp, int qsize) {
  18. if (queue.isEmpty() || qsize == 0) {
  19. queue.add(temp);
  20. return;
  21. } else if (temp &lt;= queue.peek()) {
  22. queue.add(temp);
  23. FrontToLast(queue, qsize);
  24. } else {
  25. queue.add(queue.peek());
  26. queue.remove();
  27. pushInQueue(queue, temp, qsize - 1);
  28. }
  29. }
  30. static void sort(Queue&lt;Integer&gt; queue) {
  31. if (queue.isEmpty()) {
  32. return;
  33. }
  34. int temp = queue.peek();
  35. queue.remove();
  36. sort(queue);
  37. pushInQueue(queue, temp, queue.size());
  38. /*
  39. * while (!queue.isEmpty()) { System.out.print(queue.peek() + &quot; &quot;);
  40. * queue.remove(); }
  41. */
  42. }

}

huangapple
  • 本文由 发表于 2020年8月23日 11:45:17
  • 转载请务必保留本文链接：https://go.coder-hub.com/63543167.html
  • arrays
  • java
  • queue
  • sorting
匿名

发表评论

匿名网友

:?: :razz: :sad: :evil: :!: :smile: :oops: :grin: :eek: :shock: :???: :cool: :lol: :mad: :twisted: :roll: :wink: :idea: :arrow: :neutral: :cry: :mrgreen:

确定