/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
import java.util.Scanner;
 
class Potegi {
    static Scanner in=new Scanner(System.in);
    public static void main(String[] args){
        int test;
        long a,b,c,d,e;
        test=in.nextInt();
        for(int i=0;i<test;i++){
            a=in.nextLong();
            b=in.nextLong();
            d=a%10;
            e=b%10;
            c=(int)Math.pow(d,e)%10;
            System.out.println(c);
        }
 
    }
}

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

MTEKMTI4OTMxMjM5MSAwCjEgMjMyMTMyMzEyMwoyIDMyNDMyNDM0NQozIDQzNTQzNTQzNgo0IDkwODAyMzcKNSAyMTYzMDYyCjYgOTYxMjM0MTIKNyA5MjE2MzgxMjUKOCAyMTI4OTYzNTkxCjkgMjE1MzgxMjMKMCAxODI5MzEyNTM=

11
1289312391 0
1 2321323123
2 324324345
3 435435436
4 9080237
5 2163062
6 96123412
7 921638125
8 2128963591
9 21538123
0 182931253