fork(2) download 
  1. import java.nio.file.*;
  2. import java.util.*;
  3. import java.io.File;
  4.  
  5. import static java.lang.System.out;
  6.  
  7. class Main {
  8.  
  9. 	public static void main(String[] args) {
  10. 		Database d = new Database();
  11.  
  12. 		d.add("/usr/bin");
  13. 		d.add("/usr");
  14. 		d.add("/dev");
  15. 		d.add("/dev/sda1");
  16. 		d.add("/dev/sda2");
  17. 		d.add("/home/user/Desktop/file.txt");
  18. 		d.add("/home/user/Documents/file2.txt");
  19. 		d.add("/home/user/Documents/file3.txt");
  20.  
  21. 		out.println("Final path list (using Unix paths):");
  22. 		out.println(d.getPathsList());
  23.  
  24. 		d = new Database();
  25.  
  26. 		d.add("C:\\usr\\bin");
  27. 		d.add("C:\\usr");
  28. 		d.add("C:\\dev");
  29. 		d.add("C:\\dev\\sda1");
  30. 		d.add("C:\\dev\\sda2");
  31. 		d.add("C:\\home\\user\\Desktop\\file.txt");
  32. 		d.add("C:\\home\\user\\Documents\\file2.txt");
  33. 		d.add("C:\\home\\user\\Documents\\file3.txt");
  34.  
  35. 		out.println("\nFinal path list (using Windows paths):");
  36. 		out.println(d.getPathsList());
  37. 	}
  38.  
  39. }
  40.  
  41. class Database {
  42.  
  43. 	public void add(String p) {
  44. 		root.add(Arrays.asList(p.split("\\\\|/")), 0);
  45. 	}
  46.  
  47. 	public void addAll(Collection<? extends String> list) {
  48. 		for (String p : list)
  49. 			add(p);
  50. 	}
  51.  
  52. 	public List<String> getPathsList() {
  53. 		ArrayList<String> list = new ArrayList<>();
  54. 		root.listPaths(list, "");
  55. 		return list;
  56. 	}
  57.  
  58. 	PathNode root = new PathNode("");
  59.  
  60. 	static class PathNode {
  61.  
  62. 		public final String name;
  63. 		public Map<String, PathNode> children = new HashMap<>();
  64.  
  65. 		public PathNode(String name) {
  66. 			this.name = name;
  67. 		}
  68.  
  69. 		public boolean isLeaf() {
  70. 			return children.size()==0;
  71. 		}
  72.  
  73. 		public boolean isRoot() {
  74. 			return name.isEmpty();
  75. 		}
  76.  
  77. 		public void add(List<String> path, int i) {
  78. 			String childName = path.get(i);
  79. 			PathNode child = children.get(childName);
  80.  
  81. 			if (child != null) {
  82. 				if (path.size()-i <= 1) child.children.clear();
  83. 				else child.add(path, i+1);
  84. 			} else if (!isLeaf() || isRoot()) {
  85. 				PathNode node = this;
  86. 				for (; i < path.size(); i++) {
  87. 					String key = path.get(i);
  88. 					node.children.put(key, node = new PathNode(key));
  89. 				}
  90. 			}
  91. 		}
  92.  
  93. 		public void listPaths(ArrayList<String> list, String prefix) {
  94. 			for (PathNode child : children.values()) {
  95. 				if (child.isLeaf()) list.add(prefix+child.name);
  96. 				else child.listPaths(list, prefix+child.name+File.separator);
  97. 			}
  98. 		}
  99.  
  100. 	}
  101.  
  102. }
  103.  
  104.  
Success #stdin #stdout 0.1s 320576KB
comments ()
stdin 
Standard input is empty
stdout 
Final path list (using Unix paths):
[/dev, /usr, /home/user/Desktop/file.txt, /home/user/Documents/file3.txt, /home/user/Documents/file2.txt]

Final path list (using Windows paths):
[C:/dev, C:/usr, C:/home/user/Desktop/file.txt, C:/home/user/Documents/file3.txt, C:/home/user/Documents/file2.txt]
https://ideone.com/cvqEVT
language:
Java (HotSpot 12)
created:
8 years ago
visibility:
public

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