Medium Search Techniques > Binary Search/Bisection

This is the story of Mr. and Mrs. A. They always love to play with integers. One day Mr. A asks Mrs. A to find any three integers X, Y, Z such that X = Y^Z (X, Y, Z>1). Mrs. A answers the question within 1 second. Mr. A wants to make the task harder for Mrs. A so Mr. A gives two more integers L, R. Now Mr. A asks find how many integers X, are present from L to R. Mrs. A never likes to loss to Mr. A. So Mrs. A seeks help from you. Can you do it for Mrs. A? Input: ------ First line gives an integer T (<=10^5), number of integers. Each line contains two integers L, R (1<=L<=R<=10^12) Output: ------- For every case, print case number and require answer. Look at sample output. Sample Input ------------ 2 4 9 10 20 Sample Output ------------- Case 1: 3 Case 2: 1 **Sample Input/output Explanation:** From 4 – 9 there are 3 numbers - 4 = 2^2, 8 = 2^3, 9 = 3^2 From 10 – 20 there is only one number – 16 = 2^4. 16 can also express as 16 = 4^2. But count for only once.

Shakil Ahmed