#include<stdio.h>
#include<string.h>
char sn[200];
int i,s,n,b[11][11],l,t,j;
int a[10][4]={{0,0,0,0},
              {1,1,1,1},
              {6,2,4,8},
              {1,3,9,7},
              {6,4,6,4},
              {5,5,5,5},
              {6,6,6,6},
              {1,7,9,3},
              {6,8,4,2},
              {1,9,1,9}};
int main()
{
    freopen("cifra.in","rt",stdin);
    freopen("cifra.out","wt",stdout);
    scanf("%d",&t);
    for(j=1;j<=t;j++)
    {
        scanf("%s",sn);
        l=strlen(sn);
        if(l>=2)
        {
            n=(sn[l-2]-48)*10+(sn[l-1]-48);
        }
        else
        {
            n=(sn[l-1]-48);
        }
        s=0;
        for(i=1;i<=n;i++)
        {
            s=(s+a[i%10][i%4])%10;
        }
        printf("%d\n",s);
    }
    fclose(stdout);
    fclose(stdin);
    return 0;
}