private NumberNode top; //栈顶
#endregion Fields
#region Methods
//出栈
public int? Pop()
{
if (this.top == null) return null;
else
{
int number = top.Number;
top = top.Next;
return number;
}
}
//进栈
public void Push(int number)
{
if (top == null) top = new NumberNode(number, null);
else top = new NumberNode(number, top);
}
public NumberNode(int number, NumberNode next)
{
this.Number = number;
this.Next = next;
}
