西安交通大学915-2017-编程3

#include <iostream>
#include <cstring>
using namespace std;

const int MAXSIZE = 100;

class SharedStack {
private:
    int leftTop;
    int rightTop;
    int st[MAXSIZE];
public:
    SharedStack() {
        this->leftTop = -1;
        this->rightTop = MAXSIZE;
        memset(st, 0, sizeof(st));
    }

    bool IsFull() {
        return (this->leftTop + 1) == this->rightTop;
    }

    bool IsLeftEmpty() {
        return this->leftTop == -1;
    }

    bool IsRightEmpty() {
        return this->rightTop == MAXSIZE;
    }


    int GetLeftTop() {
        if (!IsLeftEmpty()) {
            return st[this->leftTop];
        }
        return -1;
    }

    int GetRightTop() {
        if (!IsRightEmpty()) {
            return st[this->rightTop];
        }
        return -1;
    }

    void PushLeft(int x) {
        if (IsFull()) {
            cout << "the shared stack is full!" << endl;
            return;
        }
        st[++this->leftTop] = x;
    }

    void PushRight(int x) {
        if (IsFull()) {
            cout << "the shared stack is full!" << endl;
            return;
        }
        st[--this->rightTop] = x;
    }

    void PopLeft() {
        if (IsLeftEmpty()) {
            cout << "empty! can not pop" << endl;
            return;
        }
        --this->leftTop;
    }

    void PopRight() {
        if (IsRightEmpty()) {
            cout << "empty! can not pop" << endl;
            return;
        }
        ++this->rightTop;
    }
};


int main() {
    int arr[] = {1, 2, 3, 4, 5};
    int n = sizeof(arr) / sizeof(int);
    SharedStack sta;
    for (int i = 0; i < n; i++) {
        sta.PushLeft(arr[i]);
    }
    while (!sta.IsLeftEmpty()) {
        cout << sta.GetLeftTop() << " ";
        sta.PopLeft();
    }
    cout << endl;

    SharedStack stb;
    for (int i = 0; i < n; i++) {
        stb.PushRight(arr[i]);
    }
    while (!stb.IsRightEmpty()) {
        cout << stb.GetRightTop() << " ";
        stb.PopRight();
    }
    cout << endl;
    return 0;
}