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我正在寫二進制樹的刪除功能。我把我的案例分成了三份。一個有一個孩子,一個孩子不爲空。我遞歸調用刪除操作的情況下3後前,你可以看到我已經呼籲節點50.刪除操作這與75替換父節點50現在我已經刪除右子樹的節點75。所以我遞歸地運行了刪除過程。但我沒有得到期望的輸出,因爲75是在50右子樹如何解決它,這樣我能夠刪除根如何在二叉樹的遞歸操作中刪除根節點?
class BST {
public static void main(String args[]) {
Tree tr;
tr = new Tree(100);
tr.insert(50);
tr.insert(125);
tr.insert(150);
tr.insert(25);
tr.insert(75);
tr.insert(20);
tr.insert(90);
tr.delete(50);
}
}
class Tree {
public Tree(int n) {
value = n;
left = null;
right = null;
}
public void insert(int n) {
if (value == n)
return;
if (value < n)
if (right == null)
right = new Tree(n);
else
right.insert(n);
else if (left == null)
left = new Tree(n);
else
left.insert(n);
}
public Tree min() {
if(left == null)
return this;
else
return left.min();
}
public Tree max(){
if(right == null)
return this;
else
return right.max();
}
public Tree find(int n)
{
if(n == value)
return this;
else if(n > value)
return right.find(n);
else if(n < value)
return left.find(n);
else
return null;
}
public Tree findParent(int n, Tree parent)
{
if(n == value)
return parent;
else if(n > value)
return right.findParent(n, this);
else if(n < value)
return left.findParent(n, this);
else
return null;
}
public void case1(int n, Tree tr, Tree parent)
{
if(parent.left.value == n)
parent.left = null;
else
parent.right = null;
}
public void case2(int n, Tree tr, Tree parent)
{
if(parent.left!=null && parent.left.value == n)
parent.left = parent.left.left;
else
parent.right = parent.right.right;
}
public void case3(int n, Tree tr, Tree parent)
{
int min = tr.right.min().value;
tr.value = min;
tr.right.delete(min);
}
public void delete(int n) {
// fill in the code for delete
Tree tr = find(n);
Tree parent = findParent(n, this);
if(tr == null)
{
System.out.println("The tree is not present in Binary Tree");
return;
}
if(tr.left == null && tr.right == null)
{
case1(n, tr, parent);
}
else if((tr.left == null) || (tr.right == null))
{
System.out.print(tr.right.value);
System.out.print(parent.right.value);
case2(n, tr, parent);
}
else
{
case3(n, tr, parent);
}
}
protected int value;
protected Tree left;
protected Tree right;
}
*「我怎樣才能得到根本的家長嗎?」 *根不*有*父。如果是的話,它不會是* root *。 – Andreas