[DataStructure] Stack?

[DataStructure] Stack?

Stack 직접 구현해보기.

- push, pop, top

- new / delete

- Constructor / Destructor

// Stack 직접 구현해보기
// Class, Generic Class
// Array 동적할당 new / free
// Constructor / Destructor

#include <iostream>
using namespace std;

#define SIZE 1000000

template <class T>
class Stack {
private:
   int pos = 0;
   T *stack;

public:
   Stack(int size) {
      stack = new T[size];
   }

   ~Stack(int size) {
      delete stack;
   }

   T top() {
      if(isEmpty()) {
         cout << -1 << endl;
      }

      return stack[pos];
   }

   T pop() {
      if(isEmpty()) {
         cout << -1 << endl;
         return NULL;
      }

      return stack[pos--];
   }

   void push(T n) {
      stack[++pos] = n;
   }

   bool isEmpty() {
      return pos == 0;
   }
};

int main() {
   Stack<int> *s = new Stack<int>(SIZE);

   s->push(1);
   s->push(2);
   cout << s->pop() << endl;
   s->push(3);
   cout << s->pop() << endl;
   cout << s->top() << endl;
   cout << s->pop() << endl;

   return 0;
}