BST Iterator next min with O(1), O(h) complexity | C# Online Compiler

BST Iterator next min with O(1), O(h) complexity by bpraveen4u

using System;
using System.Collections.Generic;
					
public class Program
{
	public static void Main()
	{
		Console.WriteLine("Create the BST");
		var root = new Node(9);
		root.Left = new Node(6);
		root.Left.Right = new Node(7);
		root.Right = new Node(12);
		root.Right.Left = new Node(10);
		root.Right.Right = new Node(15);
		root.Right.Right.Left = new Node(14);
		
		var iterator = new BSTIterator(root);
		while(iterator.HasNext())
			Console.WriteLine(iterator.Next());
	}
}

public class BSTIterator
{
	Stack<Node> stack;
	public BSTIterator(Node root)
	{
		stack = new Stack<Node>();
		PushAll(root);
	}
	
	public bool HasNext()
	{
		return stack.Count != 0;
	}
	
	public int Next()
	{
		var node = stack.Pop();
		PushAll(node.Right);
		return node.Data;
		
	}
	
	private void PushAll(Node node)
	{
		while(node != null)
		{
			stack.Push(node);
			node = node.Left;
		}
			
	}
}

public class Node
{
	public int Data;
	public Node Left;
	public Node Right;
	
	public Node(int data)
	{
		this.Data = data;
		this.Left = this.Right = null;
	}
}

​x
 
using System;
using System.Collections.Generic;
                    
public class Program
{
    public static void Main()
    {
        Console.WriteLine("Create the BST");
        var root = new Node(9);
        root.Left = new Node(6);
        root.Left.Right = new Node(7);
        root.Right = new Node(12);
        root.Right.Left = new Node(10);
        root.Right.Right = new Node(15);
        root.Right.Right.Left = new Node(14);
        
        var iterator = new BSTIterator(root);
        while(iterator.HasNext())
            Console.WriteLine(iterator.Next());
    }
}
​
public class BSTIterator
{
    Stack<Node> stack;
    public BSTIterator(Node root)
    {
        stack = new Stack<Node>();
        PushAll(root);
    }
    
    public bool HasNext()
    {
        return stack.Count != 0;
    }
    
    public int Next()
    {
        var node = stack.Pop();
        PushAll(node.Right);
        return node.Data;
        
    }
    
    private void PushAll(Node node)
    {
        while(node != null)
        {
            stack.Push(node);
            node = node.Left;
        }
            
    }
}
​
public class Node
{
    public int Data;
    public Node Left;
    public Node Right;
    
    public Node(int data)
    {
        this.Data = data;
        this.Left = this.Right = null;
    }
}
​

make the class object here
<?xml version="1.0" encoding="utf-8"?>
<Document xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="urn:iso:std:iso:20022:tech:xsd:pain.008.001.02">
  <CstmrDrctDbtInitn>
    <GrpHdr>
      <MsgId>20101101-0001</MsgId>
      <CreDtTm>2025-06-04T18:30:07.2658269+00:00</CreDtTm>
      <Authstn>
        <Prtry>TEST</Prtry>
      </Authstn>
      <NbOfTxs>1</NbOfTxs>
      <InitgPty>
        <Nm>Bob A/S</Nm>
      </InitgPty>
    </GrpHdr>
    <PmtInf>
      <PmtInfId>PmtInfId-001</PmtInfId>
      <PmtMtd>DD</PmtMtd>
      <PmtTpInf>
        <SvcLvl>
          <Cd>SEPA</Cd>
        </SvcLvl>
        <LclInstrm>
          <Cd>CORE</Cd>
        </LclInstrm>
        <SeqTp>FRST</SeqTp>
      </PmtTpInf>
      <ReqdColltnDt>2025-06-04</ReqdColltnDt>
      <Cdtr>
        <Nm>Bob A/S</Nm>
      </Cdtr>
      <CdtrAcct>
        <Id>
          <IBAN>DK1030001234567890</IBAN>
        </Id>
      </CdtrAcct>
      <CdtrAgt>
        <FinInstnId>
          <BIC>DABADKKK</BIC>
        </FinInstnId>
      </CdtrAgt>
      <CdtrSchmeId>
        <Id>
          <PrvtId>
            <Othr>
              <Id>DK67ZZZ300077777777</Id>
              <SchmeNm>
                <Prtry>SEPA</Prtry>
              </SchmeNm>
            </Othr>
          </PrvtId>
        </Id>
      </CdtrSchmeId>
      <DrctDbtTxInf>
        <PmtId>
          <EndToEndId>20101101-5555-0001</EndToEndId>
        </PmtId>
        <InstdAmt Ccy="EUR">100</InstdAmt>
        <DrctDbtTx>
          <MndtRltdInf>
            <MndtId>5555</MndtId>
            <DtOfSgntr>2025-06-04</DtOfSgntr>
          </MndtRltdInf>
        </DrctDbtTx>
        <DbtrAgt>
          <FinInstnId>
            <BIC>DABADKKK</BIC>
          </FinInstnId>
        </DbtrAgt>
        <Dbtr>
          <Nm>Alice</Nm>
        </Dbtr>
        <DbtrAcct>
          <Id>
            <IBAN>DK3030000987654321</IBAN>
          </Id>
        </DbtrAcct>
        <InstrForCdtrAgt>ALL</InstrForCdtrAgt>
        <RmtInf>
          <Ustrd>Magazine subscription</Ustrd>
        </RmtInf>
      </DrctDbtTxInf>
    </PmtInf>
  </CstmrDrctDbtInitn>
</Document>

Last Run:	6:30:07 pm
Compile:	0.042s
Execute:	0.19s
Memory:	19.97Mb
CPU:	0.232s

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