## SNGLOOP1 - Easiest Loop 1

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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 no. 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
```

T < 10001

### Explanation

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

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 < Previous 1 2 3 4 Next > prabhav_123: 2019-01-08 19:02:36 getting back to the very basic concept of physics's derivations, finally got me an AC! Pheww Last edit: 2019-01-08 19:26:38 mcjoshi: 2016-02-27 13:25:54 took my 3 hours! AC @ping_of_death: :...खोदा पहाड़ निकली चुहिया...: agree_with_U KD : 2016-01-01 19:17:13 Damn easy but it makes my century :) Last edit: 2016-01-01 19:17:35 Siddharth Singh: 2015-12-26 12:49:34 Interesting One , the given explanation Helped me device a trial an error formula which to my surprise worked :D AC in 1 go <3 vagesh_verma: 2015-08-16 10:05:04 Last edit: 2015-08-16 10:06:32 à¤®à¥‹à¤¹à¤¨: 2015-02-06 11:51:34 Here comes a my 100th!!! :) Saksham : 2015-01-09 13:19:16 a very good indeed bourne: 2014-12-15 10:15:38 I think @Rahul Jain is correct. Not satisfying for S=0. Although the proof is easy for other values of S. Ignore the pattern and Try it :) ! Vamsi Krishna Avula: 2014-12-15 07:28:22 I was not able to prove it mathematically but observing the pattern was easy enough. NEXES: 2014-11-29 18:42:26 AC in one go..... solve it and the see the beauty of mathematics

 Added by: AvmnuSng Date: 2014-06-14 Time limit: 0.119s Source limit: 50000B Memory limit: 1536MB Cluster: Cube (Intel G860) Languages: All Resource: Abhimanyu SinghMy Problems