顺序栈

#include <iostream>
#include <assert.h>

using namespace std;

template<class T>
class STACK
{
public:
    STACK(int sz = 100):top(-1), maxLen(sz)
    {
        date = new T[sz];
        assert(date != NULL);
    }
    ~STACK(){delete []date;}
    void Push(const T& a);
    bool Pop(T& x);
    bool Top(T& x);
    bool Empty() const{return top == -1;}
    bool Full(){return top == maxLen-1;}
    int Size(){return top+1;}
    void Clear(){top = -1;}
    friend ostream& operator << (ostream& os, const STACK<T>& s)
    {
        for(int i = 0; i <= s.top; i++)
            os<<s.date[i]<<" ";
        return os;
    }
private:
    T *date;
    int top;
    int maxLen;
    void overflow();
};

template<class T>
bool STACK<T>::Top(T& x)
{
    if(Empty())return false;
    x = date[top];
    return true;
}

template<class T>
void STACK<T>::overflow()
{
    T* newdate = new T[maxLen<<1];
    if(newdate == NULL)return;
    for(int i = 0; i <= top; i++)
        newdate[i] = date[i];
    maxLen <<= 1;
    delete []date;
    date = newdate;
}

template<class T>
void STACK<T>::Push(const T& a)
{
    if(Full())overflow();
    date[++top] = a;
}

template<class T>
bool STACK<T>::Pop(T& x)
{
    if(Empty())return false;
    x = date[top--];
    return true;
}

int main()
{
    int tmp;
    STACK<int> s;
    for(int i = 0; i < 10; i++)
        s.Push(i);
    cout << s << endl;
    s.Pop(tmp);
    cout << s << endl;
    s.Top(tmp);
    cout << tmp << endl;
    return 0;
}