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  1. /**
  2.  *  Compact a list of objects Label, which is sorted on Label.amount
  3.  */
  4.  
  5. import java.util.*;
  6.  
  7. class Label {
  8.     private final String id;
  9.     private final double amount;
  10.  
  11.     public Label(String id, double amount)
  12.     {
  13.     	this.id = id;
  14.     	this.amount = amount;
  15.     }
  16.  
  17.     public String getId() {
  18.     	return this.id;
  19.     }
  20.  
  21.     public double getAmount() {
  22.     	return this.amount;
  23.     }
  24.  
  25.     public String toString() {
  26.     	return id + ": " + amount;
  27.     }
  28. }
  29.  
  30. class Ideone {
  31. 	public static List<Label> compact(List<Label> l)
  32. 	{
  33. 		Set<String> ids = new HashSet<>();
  34. 		List<Label> toret = new ArrayList<>();
  35.  
  36. 		for(Label label: l) {
  37. 			if ( !ids.contains( label.getId() ) ) {
  38. 				ids.add( label.getId() );
  39. 				toret.add( label );
  40. 			}
  41. 		}
  42.  
  43. 		return toret;
  44. 	}
  45.  
  46. 	public static void compactInPlace(List<Label> l)
  47. 	{
  48. 	    Set<String> ids = new HashSet<>();
  49.  
  50. 	    for(int i = 0; i < l.size(); ++i) {
  51. 	        if ( !ids.contains( l.get( i ).getId() ) ) {
  52. 	            ids.add( l.get( i ).getId() );
  53. 	        } else {
  54. 	            l.remove( i );
  55. 	            --i;
  56. 	        }
  57. 	    }
  58.  
  59. 	    return;
  60. 	}
  61.  
  62. 	public static void main(String[] args)
  63. 	{
  64. 		ArrayList<Label> l = new ArrayList<>();
  65.  
  66. 		l.add( new Label( "1742", 10 ) );
  67. 		l.add( new Label( "1742", 11 ) );
  68. 		l.add( new Label( "1647", 12 ) );
  69. 		l.add( new Label( "4217", 13 ) );
  70. 		l.add( new Label( "1647", 14 ) );
  71. 		l.add( new Label( "1742", 15 ) );
  72.  
  73. 		compactInPlace( l );
  74. 		System.out.println( l );
  75. 	}
  76. }
  77.  
Success #stdin #stdout 0.09s 320320KB
comments (?)
stdin 
Standard input is empty
stdout 
[1742: 10.0, 1647: 12.0, 4217: 13.0]
https://ideone.com/B4Gggt
Compact a list of objects Label, which is sorted on Label.amount
language:
Java (HotSpot 12)
created:
10 years ago
visibility:
public

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