为什么输入年龄n之后再回车窗口就关闭了?不合理啊
#include <iostream>
#include <string>
int main()
{
using namespace std;
cout<<"What is your first name?";
string strFirstname;
getline(cin,strFirstname);
cout<<"What is your last name? ";
string strLastname;
getline(cin,strLastname);
cout<<"What letter grade do you deserve? ";
char ch;
cin>> ch;
cin.get();
ch=ch+1;
cout<< "What is your age? ";
int n;
cin>> n;
cin.get();
cout <<"Name:"<<" strLastname, strFirstname \n";
cout <<"Grade:"<<'ch\n';
cout <<"Age:"<<n;
return 0;
}