#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;
						//cout<<i<<" "<<for2[i-1]<<'\n';
						break;
					}
					
					lastDigit+=for2[(i-1)%4];
					lastDigit%=10;
					//cout<<i<<" "<<for2[(i-1)%4]<<'\n';
					break;
				}
				case 3:
				{
					if(i<5)
					{
						lastDigit+=for3[i-1];
						lastDigit%=10;
						//cout<<i<<" "<<for3[i-1]<<'\n';
						break;
					}
					
					lastDigit+=for3[(i-1)%4];
					lastDigit%=10;
					//cout<<i<<" "<<for3[(i-1)%4]<<'\n';
					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;
					//cout<<i<<" "<<for7[(i-1)%4]<<'\n';
					break;
				}
				case 8:
				{
					lastDigit+=for8[(i-1)%4];
					lastDigit%=10;
					//cout<<i<<" "<<for8[(i-1)%4]<<'\n';
					break;
				}
				case 9:
				{
					lastDigit+=for9[(i-1)%2];
					lastDigit%=10;
					//cout<<i<<" "<<for9[(i-1)%2]<<'\n';
					break;
				}
			}
		}
		out<<lastDigit<<'\n';
		//cout<<lastDigit<<'\n';
	}
	
	/*out<<"\n\n\n";
	for(int i=1;i<=100;++i)
	{
		out<<i<<'\n';
	}*/
	
	in.close();
	out.close();
	
	/*int sum[100] = {
 1, 5, 2, 8, 3, 9, 2, 8, 7, 7, 8, 4, 7, 3, 8, 4, 1, 5, 4, 4, 5, 9, 6, 2,
7, 3, 6, 2, 1, 1, 2, 8, 1, 7, 2, 8, 5, 9, 8, 8, 9, 3, 0, 6, 1, 7, 0, 6, 5,
5, 6, 2, 5, 1, 6, 2, 9, 3, 2, 2, 3, 7, 4, 0, 5, 1, 4, 0, 9, 9, 0, 6, 9, 5,
0, 6, 3, 7, 6, 6, 7, 1, 8, 4, 9, 5, 8, 4, 3, 3, 4, 0, 3, 9, 4, 0, 7, 1, 0 ,0};

	ifstream in2("cifra.out");
	
	for(int i=0;i<100;++i)
	{
		int a;
		in2>>a;
		if(sum[i] != a)
		{
			cout<<i+1;
			break;
		}
	}
	
	in2.close();*/
	
	return 0;
}