165.cpp

#include <iostream>
using namespace std;
class Set{
private:
	int n;
	int * pS; //集合元素
public:
	Set(){n = 0;pS =NULL;}
	Set(Set &s){
		n = s.n;
		if (n !=0)
		{
			pS= new  int[n+1];
			for (int i =1;i<=n;i++) //集合的下标从1开始，集合中不能有重复元素
				pS[i] = s.pS[i];
		}
	}
	~Set(){
		if (pS)
		{
			delete []pS;
			pS = NULL;
			n =0;
		}
	}
		void ShowElement()const{ //输出集合的元素
		int temp = 0;
		for(int i=1;i<n;i++)
		{
			for(int j=i+1;j<n;j++)
			{
				if(pS[i] > pS[j])
				{
					temp = pS[i];
					pS[i] = pS[j];
					pS[j] = temp;
				}
			}
		}
		cout<<"{";
		for(int i =1;i<n;i++)
			cout <<pS[i]<<",";
		if (IsEmpty())
			cout<<"}"<<endl;
		else cout<<pS[n]<<"}"<<endl;
	}
	bool IsEmpty()const{return n?false:true;} //判断集合是否为空
	int size(){return n;}
	bool IsElement(int e)const {
		for (int i =1;i<=n;i++)
			if (pS[i] ==e)
			return true;
		return  false;
	}
	bool operator <=(const Set &s)const;//this <= s判断当前集合是否包于集合s
	bool operator ==(const Set &s)const; //判断集合是否相等
	Set & operator +=(int e);    // 向集合中增减元素e
	Set & operator -=(int e);    //删除集合中的元素e

	Set operator |(const Set &s)const;  //集合并
	Set operator &(const Set &s)const;//集合交
	Set operator -(const Set &s)const; //集合差
};
#include<cstring>
using namespace std;
Set & Set::operator +=(int e){
    if(!IsElement(e)){
    //    cout<<<<endl;
        int *np=new int[n+2];
        memcpy(np+1,pS+1,sizeof(int)*n);
        np[n+1]=e;
        delete[]pS;
        pS=np;
        n++;
    }
    return *this;
}
Set & Set::operator -=(int e){
    if(IsElement(e)){
        int *np=new int[n];
        int bg=0;
        for(int i=1;i<=n;i++)if(pS[i]!=e)np[++bg]=pS[i];
        delete[]pS;
        pS=np;
        n--;
    }
    return *this;
}
bool Set::operator <=(const Set &s)const{
    for(int i=1;i<=n;i++){
        if(!s.IsElement(pS[i]))return false;
    }
    return true;
}
bool Set::operator ==(const Set &s)const{
    return (*this)<=s&&s<=(*this);
}
Set Set::operator |(const Set &s)const{
    Set ans;
    for(int i=1;i<=n;i++)ans+=pS[i];
    for(int i=1;i<=s.n;i++)ans+=s.pS[i];
    return ans;
}
Set Set::operator &(const Set &s)const{
    Set ans;
    for(int i=1;i<=n;i++)if(s.IsElement(pS[i]))ans+=pS[i];
    return ans;
}
Set Set::operator -(const Set &s)const{
    Set ans;
    for(int i=1;i<=n;i++)if(!s.IsElement(pS[i]))ans+=pS[i];
    return ans;
}
int main(){
Set s;
s +=1,s+=2;
s.ShowElement();//{1,2}
s -=1;
s.ShowElement();//{2}
}