fork download
copy 
  1. /* package whatever; // don't place package name! */
  2. import java.util.*;
  3. import java.lang.*;
  4. import java.io.*;
  5.  
  6. /* Name of the class has to be "Main" only if the class is public. */
  7. public class Main {
  8.  
  9. 	public static void main (String[] args) throws java.lang.Exception {
  10. 		TreeNode<Integer> root = createTree();
  11. 		printTree(root);
  12. 		System.out.println();
  13. 		System.out.println("overwritten: " + overwriteall(root, 7, 10));
  14. 		printTree(root);
  15. 		System.out.println();
  16. 	}
  17.  
  18. 	public static TreeNode<Integer> createTree() {
  19. 		TreeNode<Integer> root = new TreeNode<Integer>(1);
  20.  
  21. 		root.left = new TreeNode<Integer>(2);
  22. 		root.left.left = new TreeNode<Integer>(3);
  23. 		root.left.right = new TreeNode<Integer>(4);
  24.  
  25. 		root.right = new TreeNode<Integer>(7);
  26. 		root.right.left = new TreeNode<Integer>(7);
  27. 		root.right.right = new TreeNode<Integer>(7);
  28.  
  29. 		return root;
  30.  
  31. 	}
  32.  
  33. 	public static <T> void printTree(TreeNode<T> root) {
  34.  
  35. 		// base case
  36. 		if(root == null) { return; }
  37.  
  38. 		// in order traversal
  39. 		printTree(root.left);
  40.  
  41. 		System.out.print(root.key);
  42. 		System.out.print(' ');
  43.  
  44. 		printTree(root.right);
  45. 	}
  46.  
  47. 	public static <T> boolean overwriteall(TreeNode<T> root, T find, T replace) {
  48. 		// base case
  49. 		if(root == null) { return false; }
  50.  
  51. 		// pre order traversal
  52. 		boolean found = false;
  53. 		if(root.key.equals(find)) { 
  54. 			found = true; 
  55. 			root.key = replace;
  56. 		}
  57.  
  58. 		// you cannot use || since that will short circuit
  59. 		// and therefore the right part of the tree will not be processed
  60. 		// if their is an element on the left part already
  61. 		return found | overwriteall(root.left, find, replace) | overwriteall(root.right, find, replace);
  62. 	}
  63.  
  64. 	public static class TreeNode<T> {
  65. 		public T key;
  66. 		public TreeNode<T> left;
  67. 		public TreeNode<T> right;
  68.  
  69. 		public TreeNode(T key) { 
  70. 			this.key = key;
  71. 		}
  72. 	}
  73. }
Success #stdin #stdout 0.04s 320576KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
3 2 4 1 7 7 7 
overwritten: true
3 2 4 1 10 10 10
https://ideone.com/KqkbxV
language:
Java (HotSpot 12)
created:
7 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!