| 1 | |
| 2 | /** |
| 3 | * Binary tree class. |
| 4 | * A binary tree is a ordered value tree with only two childs per node |
| 5 | */ |
| 6 | public class ArbreBinaire { |
| 7 | private Node<Integer> rootNode; |
| 8 | |
| 9 | ArbreBinaire() { |
| 10 | setRootNode(null); |
| 11 | } |
| 12 | |
| 13 | private void setRootNode(Node<Integer> node) { |
| 14 | rootNode = node; |
| 15 | } |
| 16 | |
| 17 | private Node<Integer> getRootNode() { |
| 18 | return rootNode; |
| 19 | } |
| 20 | |
| 21 | private boolean isEmpty() { |
| 22 | return (getRootNode() == null); |
| 23 | } |
| 24 | |
| 25 | private Node<Integer> inserer_rec(Node<Integer> currentNode, int value) { |
| 26 | if (currentNode == null) { |
| 27 | return new Node<Integer>(value); |
| 28 | } |
| 29 | if (value < currentNode.getData()) { |
| 30 | currentNode.setLeftNode(inserer_rec(currentNode.getLeftNode(), value)); |
| 31 | } else if (value > currentNode.getData()) { |
| 32 | currentNode.setRightNode(inserer_rec(currentNode.getRightNode(), value)); |
| 33 | } /* skip the equality case */ |
| 34 | return currentNode; |
| 35 | } |
| 36 | |
| 37 | public void inserer(int value) { |
| 38 | setRootNode(inserer_rec(rootNode, value)); |
| 39 | } |
| 40 | |
| 41 | private Node<Integer> supprimer_rec(Node<Integer> currentNode, int value) { |
| 42 | if (currentNode == null) { |
| 43 | return null; |
| 44 | } |
| 45 | if (value == currentNode.getData()) { |
| 46 | if (currentNode.getLeftNode() == null && currentNode.getRightNode() == null) { |
| 47 | return null; |
| 48 | } else if (currentNode.getRightNode() == null) { |
| 49 | return currentNode.getLeftNode(); |
| 50 | } else if (currentNode.getLeftNode() == null) { |
| 51 | return currentNode.getRightNode(); |
| 52 | } else { |
| 53 | /* |
| 54 | * First, we need to find the node that will replace the deleted node. |
| 55 | * We’ll use the smallest node of the node to be deleted’s right sub-tree. |
| 56 | * Then, we assign the smallest value to the node to delete and after that, |
| 57 | * we’ll delete it from the right subtree. |
| 58 | */ |
| 59 | int smallestValue = findSmallestData(currentNode.getRightNode()); |
| 60 | currentNode.setData(smallestValue); |
| 61 | currentNode.setRightNode(supprimer_rec(currentNode.getRightNode(), smallestValue)); |
| 62 | return currentNode; |
| 63 | } |
| 64 | } else if (value < currentNode.getData()) { |
| 65 | currentNode.setLeftNode(supprimer_rec(currentNode.getLeftNode(), value)); |
| 66 | } else { |
| 67 | currentNode.setRightNode(supprimer_rec(currentNode.getRightNode(), value)); |
| 68 | } |
| 69 | return currentNode; |
| 70 | } |
| 71 | |
| 72 | public void supprimer(int value) { |
| 73 | supprimer_rec(rootNode, value); |
| 74 | } |
| 75 | |
| 76 | private boolean hasDataRec(Node<Integer> currentNode, int value) { |
| 77 | if (currentNode == null) { |
| 78 | return false; |
| 79 | } |
| 80 | if (value == currentNode.getData()) { |
| 81 | return true; |
| 82 | } |
| 83 | return value < currentNode.getData() ? hasDataRec(currentNode.getLeftNode(), value) : hasDataRec(currentNode.getRightNode(), value); |
| 84 | } |
| 85 | |
| 86 | public boolean hasData(int value) { |
| 87 | return hasDataRec(rootNode, value); |
| 88 | } |
| 89 | |
| 90 | private int findSmallestData(Node<Integer> node) { |
| 91 | return node.getLeftNode() == null ? node.getData() : findSmallestData(node.getLeftNode()); |
| 92 | } |
| 93 | |
| 94 | private void afficher_rec(Node<Integer> currentNode) { |
| 95 | if (currentNode != null) { |
| 96 | afficher_rec(currentNode.getLeftNode()); |
| 97 | System.out.print(currentNode.getData() + " "); |
| 98 | afficher_rec(currentNode.getRightNode()); |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | public void afficher() { |
| 103 | afficher_rec(rootNode); |
| 104 | System.out.println(); |
| 105 | } |
| 106 | |
| 107 | private void afficher_arbre_rec(Node<Integer> currentNode, int column) { |
| 108 | if (currentNode != null) { |
| 109 | afficher_arbre_rec(currentNode.getRightNode(), column + 1); |
| 110 | for (int i = 0; i < column; i++) { |
| 111 | System.out.print(" "); |
| 112 | } |
| 113 | System.out.println(currentNode.getData()); |
| 114 | afficher_arbre_rec(currentNode.getLeftNode(), column + 1); |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | public void afficher_arbre() { |
| 119 | afficher_arbre_rec(rootNode, 1); |
| 120 | } |
| 121 | |
| 122 | public static void main(String[] args) { |
| 123 | ArbreBinaire bTree = new ArbreBinaire(); |
| 124 | |
| 125 | bTree.inserer(2); |
| 126 | bTree.inserer(6); |
| 127 | bTree.inserer(4); |
| 128 | bTree.inserer(5); |
| 129 | bTree.inserer(1); |
| 130 | bTree.inserer(0); |
| 131 | |
| 132 | bTree.afficher(); |
| 133 | bTree.afficher_arbre(); |
| 134 | |
| 135 | bTree.supprimer(4); |
| 136 | |
| 137 | bTree.afficher(); |
| 138 | bTree.afficher_arbre(); |
| 139 | |
| 140 | bTree.supprimer(6); |
| 141 | |
| 142 | bTree.afficher(); |
| 143 | bTree.afficher_arbre(); |
| 144 | |
| 145 | bTree.inserer(2); |
| 146 | bTree.inserer(7); |
| 147 | bTree.inserer(3); |
| 148 | bTree.inserer(9); |
| 149 | bTree.inserer(11); |
| 150 | bTree.inserer(10); |
| 151 | bTree.inserer(8); |
| 152 | bTree.inserer(4); |
| 153 | |
| 154 | bTree.afficher(); |
| 155 | bTree.afficher_arbre(); |
| 156 | } |
| 157 | |
| 158 | } |