C++實作一個簡單的電腦

如下所示，這是一個簡單的電腦：

#include<iostream>
#include<cstring>
using namespace std;
template <class T>
class stack
{
private:
    int top;//棧頂
    int maxtop;
    T *st;//數組
public:
    stack(int maxstacksize=10)
    {
        maxtop=maxstacksize-1;
        st=new T[maxstacksize];
        top=-1;
    }
    ~stack()
    {
        delete [] st;
    }
    //判斷棧是否已滿
    bool isfull()
    {
        return top==maxtop;
    }
    //判斷棧是否為空
    bool isempty()
    {
        return top==-1;
    }
    //向棧頂添加元素
    bool add(const T &x)
    {
        if(isfull())
        {
            cout<<"no memory"<<endl;
            return false;
        }
        top++;
        st[top]=x;
        return true;
    }
    T del()//取出并删除元素
    {
        if(isempty())
        {
            cerr<<"no element"<<endl;
        }
        T x;
        x=st[top];
        top--;
        return x;
    }
    //傳回棧頂元素值
    T returntop()
    {
        return st[top];
    }
    //清空棧
    void clear()
    {
        top=-1;
    }
    //輸出棧
    void output()
    {
        if(isempty())
        {
            cout<<"棧是空的"<<endl;
        }
        else
        {
            for(int i=0;i<=top;i++)
            {
                cout<<st[i]<<'\t';
            }
            cout<<endl;
        }
    }
};
int main()
{
    char math[20];
    char fuhao[10]={0,0,0,0,0,0,0,0,0,0};
    char shuzi[10]={'-','-','-','-','-','-','-','-','-','-'};
    int number[10];
    cout<<"輸入算數式，請以#結尾"<<endl;
    cin>>math;
    int j=0;
    int p=0;
    for(int i=0;i<20&&math[i]!='#';i++)
    {
        if(math[i]>=48&&math[i]<=57)
        {
            shuzi[j]=math[i];
            j++;
        }
        else
        {
            fuhao[p]=math[i];
            p++;
        }
    }
    for(int i=0;i<20&&math[i]!='#';i++)
    {
        if(math[i]=='('&&i!=0)
        {
            if(math[i-1]>=48&&math[i-1]<=57)
            {
                cout<<"error"<<endl;
                goto ending;
            }
        }
    }
    for(int i=0;i<10&&shuzi[i]!='-';i++)
    {
        number[i]=(int)shuzi[i]-48;
    }
    for(int i=0;i<10&&fuhao[i]!=0;i++)
    {
        if(fuhao[i]=='(')
        {
            int f=0;
            for(int q=i;q<10&&fuhao[q]!=0;q++)
            {
                if (fuhao[q]==')')
                {
                    f++;
                }
            }
            if(f==0)
            {
                cout<<"表達式錯誤"<<endl;
                goto ending;
            }
        }
    }
    return 0;
}