#include<stdio.h>
#include<string.h>
int v[101],t,x,i,j,n,v1,v2;
char s[101];
int putere(int v1,int v2)
{
	int i,p1=1;
	for(i=1;i<=v2;++i)
		p1=((p1%10)*(v1%10))%10;
	return p1%10;
}
void f()
{
	for(i=0;i<=99;++i)
		for(j=0;j<=i;++j){
			v[i]=((v[i]%10)+(putere(j+1,j+1)%10))%10;
		}
}
int main()
{
	freopen("cifra.in","r",stdin);
	freopen("cifra.out","w",stdout);
	scanf("%d",&t);
	gets(s);
	f();
	for(;t;--t){
		gets(s);
		n=strlen(s);
		if(s[1]=='\n')
			x=s[0]-'0';
		else
			x=((s[n-2]-'0')*10+(s[n-1]-'0'));
		printf("%d\n",v[x-1]);
	}
	return 0;
}