a,b=$<.map &:to_i
c=b%4
p b<1?1:case d=a%10
when 2;[6,2,4,8][c]
when 3;[1,3,9,7][c]
when 4;[6,4,6,4][c]
when 7;[1,7,9,3][c]
when 8;[6,8,4,2][c]
when 9;[1,9,1,9][c]
else d end