1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Threading.Tasks;
 5
 6 namespace TwoStacksQueue
 7 {
 8     public class Program
 9     {
10         public void Main(string[] args)
11         {
12             TwoStaksQueues twoStaksQueues = new TwoStaksQueues();
13
14             twoStaksQueues.Add(1);
15             twoStaksQueues.Add(2);
16             twoStaksQueues.Add(3);
17
18             Console.WriteLine(twoStaksQueues.Peek());
19
20             twoStaksQueues.Poll();
21
22             Console.WriteLine(twoStaksQueues.Peek());
23
24             Console.ReadLine();
25         }
26         public class TwoStaksQueues
27         {
28             public Stack<int> stacksPush;
29             public Stack<int> stackPop;
30             public TwoStaksQueues()
31             {
32                 stackPop = new Stack<int>();
33                 stacksPush = new Stack<int>();
34             }
35             public void Add(int newNumber)
36             {
37                 stacksPush.Push(newNumber);
38             }
39
40             public int Poll()
41             {
42                 if (stacksPush.Count() == 0 && stackPop.Count() == 0)
43                 {
44
45                     throw new ArgumentOutOfRangeException("DataStacks is Empty");
46                 }
47                 if (stackPop.Count() == 0)
48                 {
49                     while (stacksPush.Count() != 0)
50                     {
51                         stackPop.Push(stacksPush.Pop());
52                     }
53                 }
54                 return stackPop.Pop();
55             }
56             public int Peek()
57             {
58                 if (stacksPush.Count() == 0 && stackPop.Count() == 0)
59                 {
60                     throw new IndexOutOfRangeException("DataStacks is Empty");
61                 }
62                 if (stackPop.Count() == 0)
63                 {
64                     while (stacksPush.Count() != 0)
65                     {
66                         stackPop.Push(stacksPush.Pop());
67                     }
68                 }
69                 return stackPop.Peek();
70
71             }
72         }
73     }
74 }