Tell me what is wrong in this code of basic calculator

#1

#include
using namespace std;

int main()

{
char ch;

cin>>ch;
long int n,n1,n2;
while(ch!='X' and ch!='x')
{
	switch(ch)
	{
	case'+': 	
				cin>>n1;
				cout<<endl;
				cin>>n2;
				n=n1+n2;
				cout<<n<<endl;
				break;

	case '-':	
				cin>>n1;
				cout<<endl;
				cin>>n2;
				n=n1-n2;
				cout<<n<<endl;
				break;

	case'/': 	
				cin>>n1;
				cout<<endl;
				cin>>n2;
				n=n1/n2;
				cout<<n<<endl;
				break;

	case '%':	
				cin>>n1;
				cout<<endl;
				cin>>n2;
				n=n1%n2;
				cout<<n<<endl;
				break;

	default:   
				 cout<<"Invalid operation try again";

	}

}
return 0;

}

#2

@Subrat check for full stops and capital letter for default case.