#include <iostream>
using namespace std;
int main()
{
int t,wynik,a,b;
cin>>t;
for (int i=0;i<t;i++)
{
cin>>a>>b;
int jedn=a%10;
if (jedn==0) wynik=0;
else if (jedn==1) wynik=1;
else if (jedn==2)
{
if (b%4==1) wynik=2;
else if (b%4==2) wynik=4;
else if (b%4==3) wynik=8;
else wynik=6;
}
else if (jedn==3)
{
if (b%4==1) wynik=3;
else if (b%4==2) wynik=9;
else if (b%4==3) wynik=7;
else wynik=1;
}
else if (jedn==4)
{
if (b%2==1) wynik=4;
else wynik=6;
}
else if (jedn==5) wynik=5;
else if (jedn==6) wynik=6;
else if (jedn==7)
{
if (b%4==1) wynik=7;
else if (b%4==2) wynik=9;
else if (b%4==3) wynik=3;
else wynik=1;
}
else if (jedn==8)
{
if (b%4==1) wynik=8;
else if (b%4==2) wynik=4;
else if (b%4==3) wynik=2;
else wynik=6;
}
else
{
if (b%2==1) wynik=9;
else wynik=1;
}
cout<<wynik<<endl;
}
return 0;
}
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