Python:

Requirement:

	1	2	3
Use of recursion	Not used	Used but not accurately	The problem was solved using recursion
Drawing of hourglass	Doesn't print neatly	Prints but the spaces are not evenly distributed	Prints as expected
User Interaction	Doesn't allow the user to enter an integer	Allows the user to enter an integer but doesn't validate the input	Allows the user to enter an integer and validates the input

The program reads a single integer from the user. If that integer is less than 1, it prints an error message and stops. The hourglass base case with input 1 displays two lines with one star on each line. Otherwise, it prints a pattern of asterisks or stars (*) as shown below for an input of 4. Note that there are four stars (and spaces) on the first and last lines. ("_" is space)

*_*_*_*_ _*_*_*_ __*_*_ ___*_ __*_*_ _*_*_*_ *_*_*_*_

The program must not contain loops. Use recursion!