Discount Calculator

A store is running a promotion where they apply different discounts based on the total purchase amount:

• Less than $50 ⇒ No discount

• $50 to $100 ⇒ 10% discount

• $101 to $200 ⇒ 20% discount

• More than $200 ⇒ 30% discount

Write a program that calculates the final price after the discount is applied. The input consists of a single number representing the total purchase amount. The program should print the final price after applying the appropriate discount.