SNGLOOP1 - Easiest Loop 1

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.


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

hide comments
2014-06-30 20:12:02 P_Quantum
Pattern ;)
2014-06-29 10:42:02 abhay srinivas
observing pattern for sn is the key!!
2014-06-21 01:05:44 Ravi Shankar Mondal
cakewalk
2014-06-20 12:05:46 Koderok
What are the limits on n and m?
Edit: Limits on m and n don't matter. I got AC using 4 byte integers. Awesome problem!

Last edit: 2014-06-20 12:19:13
2014-06-19 14:55:32 Sam Winchester
Same code getting AC in C in 0.03 and TLE in JAVA !!! Why ??

Last edit: 2014-06-19 14:56:39
2014-06-17 22:56:54 AvmnuSng
@Jayesh Lata : It's never gonna work... why don't you think of something else, because it costs O(n) causing TLE
2014-06-17 18:52:44 Jayesh Lata
@Abhimanyu Singh: Can you look into my submission 11776749?
I think it should work!
2014-06-17 18:20:59 Pushkar Protik Goswami
Enjoyed solving the problem! :)
2014-06-17 18:20:59 AvmnuSng
@Valar Morghulis : give a second thought to your solution.

Last edit: 2014-06-21 00:23:08
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