After:

// Determining birth sign
if( 6 == month )
{
   if( day <= 21 )
   {
      sign = "Gemini";
   }
   else
   {
      sign = "Cancer";
   }
}
else if( 7 == month )
{
   if( day <= 21 )
   {
      sign = "Cancer";
   }
   else
   {
      sign = "Leo";
   }
}