#include <iostream>
#include <fstream>
#include <string>
using namespace std;

int pow[9][4];
int a10[10];
int a20[10];

void initPow() 
{
	for(int i=1;i<10;++i)
	{
		int a = 1;
		for(int j=0;j<4;++j) 
		{
			a *= i;
			a %=10;
			pow[i-1][j] = a;
		}
	}

	int start = 0;
	int result = 0;
	for(int j=0;j<10;++j)
	{
		result = (result+pow[j][start])%10;
		start = (start+1)%4;
		a10[j] = result;
	}

	start = 2;
	result = 0;
	for(int j=0;j<10;++j)
	{
		result = (result+pow[j][start])%10;
		start = (start+1)%4;
		a20[j] = result;
	}
}

int main(void) 
{
	ifstream in;
	ofstream out;
	//string line;
	char line[102];
	int t;

	initPow();
	in.open("cifra.in");
	out.open("cifra.out");

	in >> t;
	for(int i=0;i<t;++i)
	{
		in >> line;
		int result = 0;
		int start = 0;
		size_t length = strlen(line);
		if(length >= 2) 
		{
			int a1 = line[length - 2] - '0';
			result = 7 * a1;
			if (a1%2!=0)
				start = 2;
		}
		int a2 = line[length - 1] - '0';
		
		if(start == 0)		
			result = result+a10[a2-1];
		else
			result = result+a20[a2-1];
	
		out << result%10 << endl;
	}
	in.close();
	out.close();
	return 0;
}