#include <iostream>
#include <math.h>
using namespace std;
int main()
{
int t; // ilosc testów
cin>>t;
1<= t <=10;
for(int i=0; i<t; i++)
{
long long int a; // podstawa
1<= a <=100000000;
long long int b; // wykładnik
1<= b <=100000000;
cin >> a >>b;
int c;
if(b==4 || b==8)
{
c = int(pow(a,b));// wynik
cout<<c%10<<endl;
}
else if(a==5 && b>1)
{
cout<<"5"<<endl;
}
else if(a==6 && b>1)
{
cout<<"6"<<endl;
}
else if(a==10 && b>1)
{
cout<<"0"<<endl;
}
else
{
c = int(pow(a,(b%4)));// wynik
cout<<c%10<<endl;
}
}
return 0;
}
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