#include<fstream>
#define IN "cifra.in"
#define OUT "cifra.out"
#define MAX 99
#include<string.h>
#define MAX_SIR 101

using namespace std;

ifstream in(IN);
ofstream out(OUT);

int a[MAX], TEST, N, s, l, c1, c2;
char numar[MAX_SIR];

int main()
{
	a[0]=0;
	for(int i=1; i<=MAX; i++)
	{
		s=1;
		for(int j=0; j<i; j++)
			s=s*i%10;
		a[i]=(a[i-1]+s)%10;
	}
	in>>TEST;
	in.getline(numar, MAX_SIR);
	while(TEST)
	{
		in.getline(numar, MAX_SIR);
		l=strlen(numar);
		c2=numar[l-1]-'0';
		c1=0;
		if(l>1)
			c1=numar[l-2]-'0';
		out<<a[c1*10+c2]<<'\n';
		--TEST;
	}
	in.close();
	out.close();
	return 0;
}