SNGLOOP1 - Easiest Loop 1

no tags 

Ileana D'Cruz is taking programming classes but she is having problem in understanding while loops. She is working on following set of instructions -

INTEGER I = 0, S, U = 1010;

WHILE (I < U) {
S = (3 * S) + (5 * I);
I = I + 1;
}

Let Sk be the value assigned to INTEGER S for the iteration I = (k + 1) and n, m, p be positive integers such that m > n. Ileana knows the values of n and m but she forgot the initial value of S. She is trying to find the unit digit of p. Any initial value of S may be used. She also knows the following equality -

(2 * n + 3) * (p - 1) + (4 / 5) * [(p * Sn) - Sm] = 2 * (m - n)

Input

First line of input is T (total number of test cases). Each of next T lines contains two integers n and m.

Output

Print unit digit of p (p % 10) for each test case in separated lines.

Example

Input:
1
2 3

Output:
3

Constraints

T < 10001

Explanation

Let S = 2
S0 = 6
S1 = 23
S2 = 79
S3 = 252
Now solving the equation gives p = 3.


hide comments
AvmnuSng: 2014-06-17 22:56:54

@Jayesh Lata : It's never gonna work... why don't you think of something else, because it costs O(n) causing TLE

Jayesh Lata: 2014-06-17 18:52:44

@Abhimanyu Singh: Can you look into my submission 11776749?
I think it should work!

Pushkar Protik Goswami: 2014-06-17 18:20:59

Enjoyed solving the problem! :)

AvmnuSng: 2014-06-17 18:20:59

@Valar Morghulis : give a second thought to your solution.

Last edit: 2014-06-21 00:23:08
Rishav Goyal: 2014-06-17 18:20:59

Cool problem.!

CrazyCoder: 2014-06-17 18:20:59

please can anyone post some test cases !

Valar Morghulis: 2014-06-17 18:20:59

Hi ABhimanyu,
Can you check my submission 11770233 ?
It is giving me WA. I think I have solved correctly.

AvmnuSng: 2014-06-17 18:20:59

@mitch : yup, I placed it to "none"....

Francky: 2014-06-17 18:20:59

It's a bad spoj feature. When psetter place the problem to none, all comments are deleted, then when back to classical, comments are lost.
You can edit the problem without put it back to none, so comments can stay 'alive'. (edit) Mitch yet answered that...
==
I had an accident last week (shoulder). I will be less present for some months.
==
Jacob Platcha is a new EB member, with Mitch they will do a great job. Many thanks for them.

Last edit: 2014-06-16 10:17:55
Mitch Schwartz: 2014-06-17 18:20:59

@Abhimanyu Singh: Did you change the problem placement to "none" when editing? Doing that deletes all comments. It's a known bug.


Added by:AvmnuSng
Date:2014-06-14
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All
Resource:Abhimanyu Singh
My Problems