C# 栈=>随时读取栈中最小值

//原理：利用两个栈，一个记录最小值，一个记录数据。

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace StackGetMinValues
{
    public class Program
    {
        public void Main(string[] args)
        {
            MyStack myStack = new MyStack();
            myStack.Push(1);
            myStack.Push(15);
            myStack.Push(20);
            myStack.Push(0);
            myStack.Push(-10);
            myStack.Push(50);
            Console.WriteLine(myStack.GetMinValue());


            myStack.Pop();
            Console.WriteLine(myStack.GetMinValue());

            myStack.Pop();
            Console.WriteLine(myStack.GetMinValue());

            Console.ReadLine();

        }

    }
    public class MyStack
    {
        public Stack<int> stackData;
        public Stack<int> stackMin;
        public MyStack()
        {
            stackData = new Stack<int>();
            stackMin = new Stack<int>();
        }
        public void Push(int number)
        {
            if (number.GetType() != typeof(int)) throw new ArgumentException("必须输入数字");


            if (stackData.Count() == 0)
            {
                stackData.Push(number);
                stackMin.Push(number);
                return;
            }

            stackData.Push(number);
            if (stackMin.Peek() > number)
            {
                stackMin.Push(number);
            }
        }
        public int Pop()
        {
            if (stackData.Count() == 0) throw new IndexOutOfRangeException("栈对象为空");
            var value = stackData.Pop();
            if (value == stackMin.Peek())
            {
                stackMin.Pop();
            }
            return value;
        }
        public int GetMinValue()
        {
            if (stackMin.Count() == 0) throw new IndexOutOfRangeException("最小值栈对象为空");

            return stackMin.Peek();
        }
    }
}