while.cpp

这个是我们学校用的VC++教案

#include  <iostream.h>
main()
{
	char  response;
	cout<<"Are you feeling better about programming? (Y or N):";
	cin>>response;
  	while (response !='Y' && response !='N' && response !='y' && response !='n')
	{
   		cout<<"Error: you entered an incorrect letter."<<endl;
   		cout<<"Enter only 'Y' or 'N':";
		cin>>response;
	}
	if (response=='Y' || response=='y')
    		cout<<"I'm glad."<<endl;
	else
    		cout<<"Keep trying."<<endl;
}