Thanx alot Bruce it works

What 'm trying to do is to caculate a book pages number for a copying them.For example I want to copy pages from 25 to 30 , so the user will write 25-30the number of copies will equal sum = "30 - 25 + 1"and if the user write only a single number, the number of copies will equal "sum = sum + 1"So, th...