53 lines
985 B
Markdown
53 lines
985 B
Markdown
a) List the order in which the nodes are visited in:
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post-order.
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D,B,F,G,E,C,A
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pre-order
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A,B,D,C,E,F,G
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in-order
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D,B,F,E,G,C,A
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b)
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```java
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public class BinTreeNode
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{
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public String info;
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public BinTreeNode leftChild, rightChild;
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}
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```
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```java
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public void postTraverse( BinTreeNode node )
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{
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if ( node != null )
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{
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postTraverse( node.leftNode );
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postTraverse( node.rightNode );
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System.out.println( node.info );
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}
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}
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```
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c) The following method counts the number of nodes in the tree
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```java
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public int countTree(BinTreeNode t)
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{
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int count;
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if (t == null)
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count = 0
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else
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count = countTree(t.leftChild)+countTree(t.rightChild)+1;
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return count;
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}
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```
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countTree(root)
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-> count = countTree(t.leftChild) + countTree(t.rightChild+1)
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countTree(t.leftChild)
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-> return 1, since left and right child null
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countTree(t.rightChild)
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-> return 1, since left and right child null
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count = 1 + 1 + 1 = 3 |