下列程序输出的是( )
1 string ch="hello"; 2 if(ch[5]==NULL) 3{ 4 cout<<"right"<<endl; 5 } 6 else if (ch[5]=='\0') 7 { 8 cout<<"wrong"<<endl; 9 } 10 else 11 { 12 cout<<"hello"<<endl; 13 }