#include<stdio.h>
#include<string.h>
char s[102];
int t,m,n,v[101],i,x,y,j;
int main()
{
	freopen("cifra.in","r",stdin),freopen("cifra.out","w",stdout),scanf("%d\n",&t);
	for(i=1;i<100;++i) {
        for(x=j=i,y=1;j;j>>=1,x=(x*x)%10)
        if(j&1)
            y=(x*y)%10;
    	v[i]=(v[i-1]+y)%10;
	}
	while(t--)
		scanf("%s\n",s),m=strlen(s),n=(m>1?((s[m-2]-'0')*10+s[m-1]-'0'):(s[m-1]-'0')),printf("%d\n",v[n]);
    return 0;
}