ACPC10A - What’s Next

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According to Wikipedia, an arithmetic progression (AP) is a sequence of numbers such that the difference of any two successive members of the sequence is a constant. For instance, the sequence 3, 5, 7, 9, 11, 13 ... is an arithmetic progression with common difference 2. For this problem, we will limit ourselves to arithmetic progression whose common difference is a non-zero integer.

On the other hand, a geometric progression (GP) is a sequence of numbers where each term after the first is found by multiplying the previous one by a fixed non-zero number called the common ratio. For example, the sequence 2, 6, 18, 54 ... is a geometric progression with common ratio 3. For this problem, we will limit ourselves to geometric progression whose common ratio is a non-zero integer.

Given three successive members of a sequence, you need to determine the type of the progression and the next successive member.

Input

Your program will be tested on one or more test cases. Each case is specified on a single line with three integers (−10, 000 < a1, a2, a3 < 10, 000) where a1, a2, and a3 are distinct.

The last case is followed by a line with three zeros.

Output

For each test case, you program must print a single line of the form:
XX v
where XX is either AP or GP depending if the given progression is an Arithmetic or Geometric Progression. v is the next member of the given sequence. All input cases are guaranteed to be either an arithmetic or geometric progressions.

Example

Input:
4 7 10
2 6 18
0 0 0

Output:
AP 13
GP 54

hide comments
Nikhil Sheoran: 2014-12-05 19:53:22

Nice prob. depending on whether you use
2*b=a+c
or
b=(a+c)/2

getting started: 2014-12-02 15:04:55

giving wrong answer .. could someone rectify the mistake please?
http://www.spoj.com/submit/ACPC10A/id=13033545

Patricio: 2014-11-26 01:11:02

I think the problem with this problem is with the statements:

1. "Each case is specified on a single line with three integers (−10, 000 < a1 , a2 , a3 < 10, 000) where a1 , a2 , and a3 are distinct", and

2. All input cases are guaranteed to be either an arithmetic or geometric progressions

Dhruv k14: 2014-11-23 19:23:26

Sorry for the long comment but this is an outpour from a beginner who took nearly 2 months to get an idea of how to get around here.
My FIRST "AC IN THE FIRST GO".
and many people have commented about much difficult problems(eg-alaska,coke madness) being too easy,but honestly I found them difficult and this was by far the easiest problem.
Still a long way to go.
Feel like almost giving up on not being able to solve a problem but I must code on.
Damn, feels good.

Last edit: 2014-11-23 20:15:33
varun kumar: 2014-11-05 14:54:19

its accepting c+(c-b) but not c+(b-a)
and c*(c/b) but bot c*(b/a)
??

Gopesh Tulsyan: 2014-10-22 11:35:53

consider all cases increasing and descreasing AP and GP. took me a while to get AC :P

sivanatarajan: 2014-10-19 15:45:32

my code runs on ideone but here it got compilation error.. :(

Daksh: 2014-10-14 12:57:47

AC in first go!!

Abhishek: 2014-10-12 17:35:06

Can anyone say what's wrong with my code?

[edit by cyclops: Please read the notes at the bottom; the first one is "Don't post any source code here."]

Last edit: 2014-10-12 18:12:12
Rounaq Jhunjhunu Wala: 2014-10-08 05:24:11

what if the series is both AP and GP


Added by:Omar ElAzazy
Date:2010-11-30
Time limit:1.799s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64
Resource:ACPC 2010