LCPC11B - Co-Prime

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Given a number N, you are asked to count the number of integers between A and B inclusive which are relatively prime to N.

Two integers are said to be co-prime or relatively prime if they have no common positive divisors other than 1 or, equivalently, if their greatest common divisor is 1. The number 1 is relatively prime to every integer.

Input Specification

The first line on input contains T (0 < T <= 100) the number of test cases, each of the next T lines contains three integers A, B, N where (1 <= A <= B <= 1015) and (1 <= N <= 109).

Output Specification

For each test case, print the number of integers between A and B inclusive which are relatively prime to N. Follow the output format below.

Sample Input


1 10 2

3 15 5

Sample Output

Case #1: 5

Case #2: 10

In the first test case, the five integers in range [1,10] which are relatively prime to 2 are {1,3,5,7,9}.


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Kushal Saharan: 2014-06-24 15:16:01

Good Question! Learnt something new :)

nbcool: 2013-02-03 09:23:52

Is anybody getting TLE in this code

saivikneshwar: 2012-11-26 12:19:32

This problem is pretty similar to HNUMBERS.

Ehor Nechiporenko: 2012-11-07 22:16:23

@Mehmet, HNUMBERS is very close to this problem, but simpler and has smaller constraints

mehmetin: 2012-11-07 14:10:54

Wasn't there a previous problem similar to this?

PS There is EASYMATH which is similar, but this problem is a little different and also requires some effort. I would say it's NOT tutorial.

Last edit: 2012-11-07 17:38:28
(Tjandra Satria Gunawan)(曾毅昆): 2012-11-07 18:25:04

Fine, this problem is not tutorial :P

Last edit: 2012-11-07 18:24:59
Ehor Nechiporenko: 2012-11-06 22:09:12

Pretty simple task) Happy to resolve it first

Last edit: 2012-11-06 22:11:09

Added by::-P
Time limit:0.293s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64