#include<stdio.h>
#include<string.h>
int pow(int a,int n){
	int x=1;
	for(int i=0;i<n;i++)
		x=x*a;
	return x;
}
int main (){
	freopen("cifra.in","r",stdin);
	freopen("cifra.out","w",stdout);
	char s[1000];
	int n,nr,t,sum=0,dou,gr,i,x,y;
	scanf("%d\n",&t);
	while(t--){
		sum=0;
		gets(s);
		nr=strlen(s);
		if(nr==1)
			n=s[nr-1]-'0';
		else
			n=(s[nr-2]-'0')*10+s[nr-1]-'0';
		//printf("%d\n",n);
		gr=n/20;
		dou=n-gr*20;
		sum=(sum+4*gr)%10;
		for(i=1;i<=dou;i++){
			x=i%10;
			y=i%4;
			if(y==0)
				y=4;
			sum=sum+pow(x,y)%10;
		}
		printf("%d\n",sum%10);
	}
	return 0;
}