#include <iostream>
#include <fstream>
#include <string>
#include <math.h>
using namespace std;

string nr;

int T;
ifstream in("cifra.in");
ofstream out("cifra.out");

int for2[] = {2,4,8,6};
int for3[] = {3,9,7,1};
int for4[] = {4,6};
int for7[] = {7,9,3,1};
int for8[] = {8,4,2,6};
int for9[] = {9,1};

int main()
{
	in>>T;
	while(T--)
	{
		in>>nr;
		int impNr = 0;
		int impNrDigits = 0;
		int pz = nr.size()-1;
		while(pz>=0 && impNrDigits<2)
		{
			impNr+= (nr[pz]-'0') * pow(10,impNrDigits);
			++impNrDigits;
			pz--;
		}
		int lastDigit = 0;
		
		for(int i=0;i<=impNr;++i)
		{
			switch(i%10)
			{
				case 0: 
				{
					lastDigit+=0;
					lastDigit%=10;
					break;
				}
				case 1:
				{
					lastDigit+=1;
					lastDigit%=10;
					break;
				}
				case 2:
				{
					if(i<5)
					{
						lastDigit+=for2[i-1];
						lastDigit%=10;
						break;
					}
					
					lastDigit+=for2[(i-1)%4];
					lastDigit%=10;
					break;
				}
				case 3:
				{
					if(i<5)
					{
						lastDigit+=for3[i-1];
						lastDigit%=10;
						break;
					}
					
					lastDigit+=for3[(i-1)%4];
					lastDigit%=10;
					break;
				}
				case 4:
				{
					lastDigit+=for4[(i-1)%2];
					lastDigit%=10;
					//cout<<i<<" "<<for4[(i-1)%2]<<'\n';
					break;
				}
				case 5:
				{
					lastDigit+=5;
					lastDigit%=10;
					break;
				}
				case 6:
				{
					lastDigit+=6;
					lastDigit%=10;
					break;
				}
				case 7:
				{
					lastDigit+=for7[(i-1)%4];
					lastDigit%=10;
					break;
				}
				case 8:
				{
					lastDigit+=for8[(i-1)%4];
					lastDigit%=10;
					break;
				}
				case 9:
				{
					lastDigit+=for9[(i-1)%2];
					lastDigit%=10;
					break;
				}
			}
		}
		out<<lastDigit<<'\n';
	}
	
	
	in.close();
	out.close();
	
	
	return 0;
}