Thêm phần tử vào mảng

class sach
{
	public:
		string Ten;
		int Ma;
		string TG;
		sach()
		{
			Ten="";
			Ma=0;
			TG="";
	 }
	 void Xuat(sach A[],int n){
	 	for(int i=0;i<n;i++)
			{
				cout<<"quyen sach thu ["<<i+1<<"]:"<<endl;
				cout<<A[i].Ten<<endl;
				cout<<A[i].Ma<<endl;
				cout<<A[i].TG<<endl;
				}}
		void Nhap(sach A[])
		{
			
			
				cin.ignore();
				cout<<"moi nhap Ten Sach:"<<endl;
				getline(cin,Ten);
				cout<<"moi nhap Ma sach:"<<endl;
				cin>>Ma;
			cin.ignore();
				cout<<"moi nhap TG:"<<endl;
				getline(cin,TG);
			
			
			
		}
		
		void xoa(sach A[],int n, int k)
		{
			for(int i=k-1;i<n-1;i++)
			{
				A[i]=A[i+1];
			}
			n--;
		}
};
sach A[100];
int dem=0;
int main()
{
	int n;
	cout<<"1.Nhap them sach:"<<endl;
	cout<<"2.kiem tra thong tin sach:"<<endl;
	cout<<"3.thoat "<<endl;
	cout<<"4.xoa thong tin sach:"<<endl;
	do{
	cout<<"moi nhap lua chon cua ban:"<<endl;
	cin>>n;
	if(n>4||n<1) {cout<<"ban nhap sai roi moi nhap lai"<<endl;}
		{
			switch(n)
			{
				case 1:
					{
						int k;
						cout<<"moi nhap so luong sach muon them :"<<endl;
						cin>>k;
						for(int i=0;i<k;i++)
						{
							
						A[i].Nhap(A);
							
							dem++;
						}
						
						break;	
					}
				case 2:
					{
						sach q1;
						q1.Xuat(A,dem);
						break;
					}
					
				case 3:
					{
						return 0;
						break;
					}
				case 4:
					{	int k;
						cout<<"moi chon sach can xoa:"<<endl;
						cin>>k;
						sach q1;
						q1.xoa(A,n,k);
					}
			}
		}
	
}while(n!=3);

}

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