/**~*~*~*
CIS 22C
Project: Stack of strings

Written by: Iurii Tatishchev
IDE: CLion
*~*/
#include <iostream>
#include <string>

using namespace std;

class Stack_str {
private:
    // Structure for the stack nodes
    struct StackNode {
        string value;           // Value in the node
        StackNode *next;     // Pointer to next node
    };

    StackNode *top;          // Pointer to the stack top
    int length;

public:
    Stack_str(){ top = NULL; length = 0; }    //Constructor
    //~Stack_str();                           // Destructor

    // Stack operations
    bool isEmpty() {
        return length == 0;
    }

    bool push(string);

    // string pop();
    string peek() {
        return top->value;
    }

    int getLength() {
        return length;
    }
};

/**~*~*~*
  Member function push: pushes the argument onto the stack.
*~**/
bool Stack_str::push(string item) {
    StackNode *newNode; // Pointer to a new node

    // Allocate a new node and store item there.
    newNode = new StackNode;
    if (!newNode)
        return false;
    newNode->value = item;

    // Update links and counter
    newNode->next = top;
    top = newNode;
    length++;

    return true;
}


int main() {

    Stack_str s;
    string item;


    getline(cin, item);
    while (item != "0") {
        s.push(item);
        cin.clear();
        getline(cin, item);
    }

    cout << s.getLength() << "\n";
    cout << (s.isEmpty() ? "Empty Stack!" : s.peek()) << "\n";
    cout << s.getLength() << "\n";

    return 0;
}