import std.algorithm, std.container, std.conv, std.math, std.range, std.typecons, std.stdio, std.string;

auto rdsp(){return readln.splitter;}
void pick(R,T)(ref R r,ref T t){t=r.front.to!T;r.popFront;}
void readV(T...)(ref T t){auto r=rdsp;foreach(ref v;t)pick(r,v);}

void main()
{
  string n; readV(n);
  string m; readV(m);

  if (m == "0") {
    writeln(1);
    return;
  }

  auto n1 = n[$-1..$].to!int;
  auto m2 = m[$-min(m.length, 2)..$].to!int;
  writeln(n1^^((m2+3)%4+1) % 10);
}