二叉树的增删改查

Posted 2021-01-10 xhlwjy

package erTree;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Stack;

public class erTree {
 public static void main(String[] args) {
  BiTree bt = new BiTree();

  bt.insert(50, 1.5);
  bt.insert(25, 1.7);
  bt.insert(75, 1.9);
  bt.insert(55, 1.0);
  bt.insert(20, 1.1);
  bt.insert(30, 2.0);
  bt.insert(5, 0.2);
  bt.insert(27, 0.1);
  bt.insert(40, 0.3);
  bt.insert(28, 0.7);
  HuffmanTreeBuilder hb =new HuffmanTreeBuilder();
  hb.ss();
 }
}

class Node {
 Person p1 = new Person();
 public Node left;
 public Node right;
 public int value;
}

class Person {
 int iDate;
 double fDate;
}

class BiTree {
 Node root;

 public BiTree() {
  this.root = root;
 }

 public Node find(int key) {
  Node currect = root;
  while (currect.p1.iDate != key) {
   if (key < currect.p1.iDate) {
    currect = currect.left;
   } else {
    currect = currect.right;
   }
   if (currect == null) {
    return null;
   }
  }
  return currect;
 }

 public void insert(int id, double dd) {
  Node newNode = new Node();
  newNode.p1.iDate = id;
  newNode.p1.fDate = dd;
  if (root == null) {
   root = newNode;
  } else {
   Node currect = root;
   Node parent;
   while (true) {
    parent = currect;
    if (id < currect.p1.iDate) {
     currect = currect.left;
     if (currect == null) {
      parent.left = newNode;
      return;
     }
    } else {
     currect = currect.right;
     if (currect == null) {
      parent.right = newNode;
      return;
     }
    }
   }
  }
 }

 public void delete(int key) {
  Node currect = root;
  Node parent = root;
  boolean isLeft = true;
  while (currect.p1.iDate != key && currect != null) {
   parent = currect;
   if (key > currect.p1.iDate) {
    isLeft = true;
    currect = currect.right;
   } else {
    isLeft = false;
    currect = currect.left;
   }
  }

  if (currect.left == null && currect.right == null) {
   if (currect == root) {
    root = null;
   } else if (isLeft) {
    parent.right = null;
   } else {
    parent.left = null;
   }
  } else if (currect.right == null) {
   if (currect == root) {
    root = root.left;
   } else if (isLeft) {
    parent.right = currect.left;
   } else {
    parent.left = currect.left;
   }
  } else if (currect.left == null) {
   if (currect == root) {
    root = root.right;
   } else if (isLeft) {
    parent.left = currect.right;
   } else {
    parent.right = currect.right;
   }
  } else if (currect.left != null && currect.right != null) {
   Node houji = currect.right;
   Node houjiparent = currect.right;
   while (houji.left != null) {
    houjiparent = houji;
    houji = houji.left;
   }
   if (currect == root) {
    root = houji;
   } else {
    currect.p1.iDate = houji.p1.iDate;
    if (houji.right == null) {
     houjiparent.left = null;
    } else {
     houjiparent.left = houji.right;
    }
   }
  }
 }

 // 先序遍历非递归
 public void inOrder(Node localRoot) {
  Stack<Node> stack = new Stack<Node>();
  if (localRoot != null) {
   stack.push(localRoot);
   while (!stack.empty()) {
    localRoot = stack.pop();
    System.out.print(localRoot.p1.iDate + ",");
    if (localRoot.right != null) {
     stack.push(localRoot.right);
    }
    if (localRoot.left != null) {
     stack.push(localRoot.left);
    }
   }
  }
 }

 // 先序遍历递归
 public void inOrder1(Node localRoot) {
  if (localRoot != null) {
   System.out.print(localRoot.p1.iDate + ",");
   inOrder(localRoot.left);
   inOrder(localRoot.right);
  }
 }

 // 中序遍历非递归
 public void iterativeInorder(Node localRoot) {
  Stack<Node> stack = new Stack<Node>();
  while (localRoot != null || !stack.empty()) {
   while (localRoot != null) {
    stack.push(localRoot);
    localRoot = localRoot.left;
   }
   if (!stack.empty()) {
    localRoot = stack.pop();
    System.out.print(localRoot.p1.iDate + ",");
    localRoot = localRoot.right;
   }
  }
 }

 // 中序遍历递归
 public void iterativeInorder1(Node localRoot) {
  if (localRoot != null) {
   iterativeInorder1(localRoot.left);
   System.out.print(localRoot.p1.iDate + ",");
   iterativeInorder1(localRoot.right);
  }
 }

 // 后序遍历
 public void iterativePostorder(Node node) {
  if (node == null)
   return;
  Stack<Node> s = new Stack<Node>();
  Node curNode; // 当前访问的结点
  Node lastVisitNode; // 上次访问的结点
  curNode = node;
  lastVisitNode = null;
  // 把currentNode移到左子树的最下边
  while (curNode != null) {
   s.push(curNode);
   curNode = curNode.left;
  }
  while (!s.empty()) {
   curNode = s.pop(); // 弹出栈顶元素
   // 一个根节点被访问的前提是：无右子树或右子树已被访问过
   if (curNode.right != null && curNode.right != lastVisitNode) {
    // 根节点再次入栈
    s.push(curNode);
    // 进入右子树，且可肯定右子树一定不为空
    curNode = curNode.right;
    while (curNode != null) {
     // 再走到右子树的最左边
     s.push(curNode);
     curNode = curNode.left;
    }
   } else {
    // 访问
    System.out.print(curNode.p1.iDate + ",");
    // 修改最近被访问的节点
    lastVisitNode = curNode;
   }
  } // while
 }

 // 求最小值
 public Node min() {
  Node current, last = null;
  current = root;
  while (current != null) {
   last = current;
   current = current.left;
  }
  return last;
 }

 // 求最大值
 public Node max() {
  Node current, last = null;
  current = root;
  while (current != null) {
   last = current;
   current = current.right;
  }
  return last;
 }

 // 求最大深度
 public int maxDepth(Node node) {
  if (node == null) {
   return 0;
  }
  int left = maxDepth(node.left);
  int right = maxDepth(node.right);
  return Math.max(left, right) + 1;
 }

 // 求最小深度
 public int minDepth(Node node) {
  if (node == null) {
   return 0;
  }
  int left = maxDepth(node.left);
  int right = maxDepth(node.right);
  return Math.min(left, right) + 1;
 }

 // 求二叉树中节点个数
 public int number(Node node) {
  if (node == null) {
   return 0;
  }
  int left = number(root.left);
  int right = number(root.right);
  return left + right + 1;
 }

}