删除二叉搜索树中的最小值？

Question

我尝试使用removeMin()方法按排序顺序打印出我的二叉搜索树，但输出不正确。

这是我的代码：

public Node removeMin(Node insertNode){

  Node parentNode =root;
  if (insertNode.left != null){
    return removeMin(insertNode.left);
  }
  if (insertNode.right ==null){
    parentNode.left = null;
  }else {
    parentNode.left = removeMin(insertNode.right);
  }
  return insertNode;
}

Answer 1

检查node == NULL

public Node removeMin(Node root){
    if(root == NULL)
        return NULL;
    if (root.left != NULL){
        return removeMin(root.left);
    }
    if (insertNode.right == NULL){
        Node temp = root;
        root = NULL;
        return temp;
    }
    else {
       return removeMin(root.right);
    }

  }

未选中..

Answer 2

试试这个

private Node removeMin(Node node){
    if(node.left.left == null) {
        Node minNode = node.left;
        node.left = node.left.right;
        minNode.right = null;
        return minNode;
    } else {
        return removeMin(node.left);
    }
}

public Node removeMin() {
    if(root == null) {
        return null;
    } else if(root.left != null) {
        return removeMin(root);
    } else {
        Node minNode = root;
        root = root.right;
        minNode.right = null;
        return minNode;
    }
}