static void Main(string[] args)
{
Stack<string> books = new Stack<string>();
books.Push("Programming WPF");
books.Push("The Philosophy Book");
books.Push("Heat and Thermodynamics");
books.Push("Harry Potter and the Chamber of Secrets");
Console.WriteLine("ALL BOOKS:");
foreach (string title in books)
{
Console.WriteLine(title);
}
string topItem = books.Pop();
string topItem = books.Peek(); // Allows you to peek at the top item and not remove it
Console.WriteLine("\r\nTOP ITEM IS: " + topItem);
Console.WriteLine("\r\nALL BOOKS:");
foreach (string title in books)
{
Console.WriteLine(title);
}
}
static void Main(string[] args)
{
var numberOfQueries = int.Parse(Console.ReadLine());
var stack = new Stack<int>();
var maxStack = new Stack<int>();
maxStack.Push(int.MinValue);
for (int i = 0; i < numberOfQueries; i++)
{
var parameters = Console.ReadLine().Split().Select(int.Parse).ToArray();
var operation = parameters[0];
switch (operation)
{
case 1:
var number = parameters[1];
stack.Push(number);
if (stack.Peek() > maxStack.Peek())
{
maxStack.Push(stack.Peek());
}
break;
case 2:
var num = stack.Pop();
if (num == maxStack.Peek())
{
maxStack.Pop();
}
break;
case 3:
Console.WriteLine(maxStack.Peek());
break;
default:
break;
}
}
}
