#include<stdio.h>
#include<string.h>
int pk[21];
void init()
{
	int cop;
	for(int i=1;i<=20;++i)
	{
		cop=i;
		pk[i]=1;
		while(cop--)
			pk[i]=pk[i]*i%10;
		pk[i]=(pk[i-1]+pk[i])%10;
	}
}
inline int read()
{
	char buff[101];
	int nr,rez;
	gets(buff);
	nr=strlen(buff);
	if(nr==1)
		return buff[0]-'0';
	rez=(buff[nr-2]-'0')*10+(buff[nr-1]-'0');
	return rez;
}
int main()
{
	int numb,sum,t,i;
	freopen("cifra.in","r",stdin);
	freopen("cifra.out","w",stdout);
	init();
	scanf("%d\n",&t);
	while(t--)
	{
		sum=0;
		numb=read();
		sum+=(numb/20)*4;
		numb%=20;
		sum+=pk[numb];
		printf("%d\n",sum%10);
	}
	return 0;
}