LASTDIG - The last digit


Nestor was doing the work of his math class about three days but he is tired of make operations a lot and he should deliver his task tomorrow. His math’s teacher gives him two numbers a and b. The problem consist of finding the last digit of the potency of base a and index b. Help Nestor with his problem. You are given two integer numbers: the base a (0 <= a <= 20) and the index b (0 <= b <= 2,147,483,000), a and b both are not 0. You have to find the last digit of ab.

Input

The first line of input contains an integer t, the number of test cases (t <= 30). t test cases follow. For each test case will appear a and b separated by space.

Output

For each test case output an integer per line representing the result.

Example

Input:
2
3 10
6 2

Output: 9 6

hide comments
tejal: 2015-06-14 18:51:42

There is a problem in the test data. There is a test case of 0,0 in-spite of them mentioning it wouldn't be there and the answer they expect is 1

rsd_unleashed: 2015-06-11 17:08:37

Input won't contain (0,0) (1,0) (0,1) cases...

Last edit: 2015-06-11 17:09:31
Ankush : 2015-06-08 10:19:38

Learned a new algorithm. Loved it :)

cassiano: 2015-06-08 00:10:40

Solved in Java, but 700 bytes is still ridiculous. My code actually had 692 bytes, but still got the message about the 700B size limit. Had to remove all line breaks and reduce all variable names to 1 letter... =/

kp: 2015-06-05 05:54:03

check for the case a != 0 and b = 0

akar sheth: 2015-05-31 22:30:16

finally got AC :)

Parth Vyas: 2015-05-29 22:16:37

tried all the cases,even 0<=b<=2147438000. works perfectly on my pc, here it shows compilation error -_-.

studmax: 2015-05-28 16:40:04

@simon This question can be easily solved by hard coding the periodicity of last digit for a given base (with different exponents). To avoid this spoj has put the restriction on size limit on source code... Helps you to learn new algo ...:)

KavishD: 2015-05-06 17:14:30

Modular exponentiation ftw!!

bholagabbar: 2015-04-08 13:48:39

It's impossible to make a 700kb solution in java

re(vamsi): It is solvable. ranks/LASTDIG/lang=JAVA

Last edit: 2015-04-08 15:40:06

Added by:Jose Daniel Rodriguez Morales
Date:2008-12-01
Time limit:1s
Source limit:700B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: GOSU
Resource:Own