这是我的代码。 LinkedBinaryTree和Position类来自教科书,如果需要,我可以为那些人提供代码,但我不确定是否有必要。该类应该能够以如下方式将新节点添加到二叉树中:对于每个内部节点,存储在父节点左侧的元素小于父节点的元素,而存储在右侧的元素父节点的大小大于父节点的大小,因此应该创建一个二进制搜索树。问题是当我打印出结果树时(见下文),我只会得到根元素。
import net.datastructures.LinkedBinaryTree;
import net.datastructures.Position;
import java.util.Iterator;
public class IntLinkedBinaryTree extends LinkedBinaryTree<Integer> {
// define instance variables and methods, including a constructor(s) as needed
private Position<Integer> root;
private int size;
/**
* Creates an empty IntLinkedBinaryTree
*/
public IntLinkedBinaryTree() {
root = null;
size = 0;
}
/**
* Add a new node with e to the tree rooted at position p
*
* @param p The root of the tree to which new node is added
* @param e The element of the new node
* @return If a node with e does not exist, a new node with e is added and
* reference to the node is returned. If a node with e exists, null is returned.
*/
public Position<Integer> add(Position<Integer> p, Integer e) {
if (p == null) {
root = addRoot(e);
size++;
return p;
}
Position<Integer> x = p;
Position<Integer> y = x;
while (x != null) {
if (x.getElement().equals(e)) {
return null;
} else if (x.getElement() > e) {
y = x;
x = left(x);
} else {
y = x;
x = right(x);
}
} // end while
Position<Integer> temp;
if (y.getElement() > e) {
temp = createNode(e, validate(y), null, null);
addLeft(temp, e);
} else {
temp = createNode(e, validate(y), null, null);
addRight(temp, e);
}
size++;
return temp;
}
public static void main(String[] args) {
// create a new binary tree instance
IntLinkedBinaryTree t = new IntLinkedBinaryTree();
// add some integers
t.add(t.root, 100);
t.add(t.root, 50);
t.add(t.root, 150);
t.add(t.root, 70);
// print all integers in the tree in increasing order
// after adding above four integers, the following should be printed
// 50 70 100 150
Iterator<Position<Integer>> it = t.inorder().iterator();
System.out.println();
while (it.hasNext()) {
System.out.print(it.next().getElement() + " ");
}
System.out.println();
}
}
我只得到100作为输出,而我正要拔头发。 LinkedBinaryTree类提供了addRoot(),addLeft()和addRight(),inorder()和iterator()等方法,并且整个main方法也是如此。当我使用intelliJ调试代码时,它调用了add *方法,但是只有100张打印到控制台。
最佳答案
我将addLeft()和addRight()更改为setLeft()和setRight()。现在可以正常工作,但是我不确定为什么,因为addLeft / Right()在超类中调用setLeft / Right()。
关于java - 为什么在我的LinkedBinaryTree实现中仅添加了根,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/49547167/