#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>

unsigned int cifra(unsigned int n)
{
	unsigned int m = n % 10;

	switch (m)
	{
	case 0: return 0; 
	case 1: return 1;
	case 2: 
	{
		switch (n % 4)
		{
		case 0: return 6;
		case 1: return 2;
		case 2: return 4;
		case 3: return 8;
		}
	}
	case 3:
	{
		switch (n % 4)
		{
		case 0: return 1;
		case 1: return 3;
		case 2: return 9;
		case 3: return 7;
		}
	}
	case 4:
	{
		switch (n % 2)
		{
		case 0: return 6;
		case 1: return 4;
		}
	}
	case 5: return 5;
	case 6: return 6;
	case 7: 
		switch (n % 4)
		{
		case 0: return 1;
		case 1: return 7;
		case 2: return 9;
		case 3: return 3;
		}
	case 8:
		switch (n % 4)
		{
		case 0: return 6;
		case 1: return 8;
		case 2: return 4;
		case 3: return 2;
		}
	case 9:
		switch (n % 2)
		{
		case 0: return 1;
		case 1: return 9;
		}

	}
	return 0;
}

int main()
{
	unsigned int T, v[99999], t[99999];
	char c[99999], s[3];
	FILE* f = fopen("cifra.in", "r"), *g = fopen("cifra.out", "a");
	fgets(c, 99998, f);
	sscanf(c, "%u", &T);

	v[0] = 0;


	for (unsigned int j = 1; j <= 100; j++)
		v[j] = (v[j - 1] + cifra(j))%10;

	for (unsigned int i = 1; i <= T; i++)
	{
		t[i] = 0;

		fgets(c, 99998, f);
		if (strlen(c) > 2)
		{
			s[0] = c[strlen(c) - 3];
			s[1] = c[strlen(c) - 2];
		}
		else {
			s[0] = c[0];
			s[1] = c[1];
		}
		
		sscanf(s, "%u", &t[i]);
		
		fprintf(g, "%u\n", v[t[i]]);
		fflush(stdout);
	}

	fclose(f);
	fclose(g);
	
	return 0;
}