之前我们已经了解过了 二叉树的遍历,现在我们一起来看一下,二叉树的查找。
class BinaryTree {
private HeroNode root;
public void setRoot(HeroNode root) {
this.root = root;
}
//前序查找
public HeroNode preOrderSearch(int no) {
if (root != null) {
return root.preOrderSearch(no);
} else {
return null;
}
}
public HeroNode infixOrderSearch(int no) {
if (root != null) {
return root.infixOrderSearch(no);
} else {
return null;
}
}
public HeroNode postOrderSearch(int no) {
if (root != null) {
return root.postOrderSearch(no);
} else {
return null;
}
}
}
class HeroNode {
private int no;
private String name;
private HeroNode left;
private HeroNode right;
public HeroNode(int no, String name) {
this.no = no;
this.name = name;
}
public int getNo() {
return no;
}
public void setNo(int no) {
this.no = no;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public HeroNode getLeft() {
return left;
}
public void setLeft(HeroNode left) {
this.left = left;
}
public HeroNode getRight() {
return right;
}
public void setRight(HeroNode right) {
this.right = right;
}
@Override
public String toString() {
return "HearNode{" +
"no=" + no +
", name='" + name + '\'' +
'}';
}
//前序查找
public HeroNode preOrderSearch(int no) {
if (this.no == no) {
return this;
}
HeroNode resNode = null;
if (this.left != null) {
resNode = this.left.preOrderSearch(no);
}
if (resNode != null) {
return resNode;
}
/*
1.左递归前序查找,找到节点就返回,否则继续判断
2. 当前节点的右子节点是否为空如果不为空则继续
*/
if (this.right != null) {
resNode = this.right.preOrderSearch(no);
}
return resNode;
}
//中序查找
public HeroNode infixOrderSearch(int no) {
HeroNode resNode = null;
if (this.left != null) {
resNode = this.left.preOrderSearch(no);
}
if (resNode != null) {
return resNode;
}
if (this.no == no) {
return this;
}
if (this.right != null) {
resNode = this.right.preOrderSearch(no);
}
return resNode;
}
//后序查找
public HeroNode postOrderSearch(int no) {
HeroNode resNode = null;
if (this.left != null) {
resNode = this.left.preOrderSearch(no);
}
if (resNode != null) {
return resNode;
}
if (this.right != null) {
resNode = this.right.preOrderSearch(no);
}
if (resNode != null) {
return resNode;
}
if (this.no == no) {
return this;
}
return resNode;
}
}