To check vowel...

#include<iostream.h>
void main()
{
 char ch;

cout<<"Enter a character\n";
cin>>ch;

switch(ch)
{
case 'a':
case 'A':
case 'e':
case 'E':
case 'i':
case 'I':
case 'o':
case 'O':
case 'u':
case 'U':
cout<<ch<<" is a vowel.\n";
break;
default:
cout<<ch<<" is not a vowel.\n";
}

}