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 a^{b}.
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
skeukry:
20170207 19:01:03
Help! Why do I get WA (18717784) (haskell)? :c It works for every test case even b=0 or a=0 Last edit: 20170207 19:03:57 

giriprasad kemburu:
20170127 13:06:26
Got AC after 4 WA.Forgot to check 0 in power[any power zero =1].


dgfreak:
20170124 15:29:59
If you're using exponentiation, you're doing it wrong :D 

dhruv19:
20161220 14:55:46
@koko4nut please help me i am getting a TLE how can i optimize my code


tejman1809:
20161216 15:26:54
@koko4nut Thank You, but what exactly is the mistake because of which its not getting accepted? 

koko4nut:
20161216 09:24:21
@tejman1809 . Your test is successful returning "0" when a = b = 0.


tejman1809:
20161216 08:20:30
Can someone please check what's wrong with my code?Already received 12 WAs.


koko4nut:
20161215 22:21:50
I got a runtime error (NZEC) but run just fine at home and on ideone.


yash_code_guy:
20161215 19:38:16
I used the logic that the last digit that we will get from a^b will be same as that we will get from a^m where m=b%4


darpanjbora:
20161213 16:17:55
AC in one go with Java. ;) 
Added by:  Jose Daniel Rodriguez Morales 
Date:  20081201 
Time limit:  1s 
Source limit:  700B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: GOSU 
Resource:  Own 