#include<stdio.h>
#include<string.h>
int main(){
       FILE*in=fopen("cifra.in","r");
       FILE*out=fopen("cifra.out","w");
       int t,n,i,x,s,j,j1,aux,k,p;
       char nr[100];
       fscanf(in,"%d",&t);
       for(i=0;i<t;i++){
               fscanf(in,"%s",nr);
               n=strlen(nr);
               if(n==1)
                       x=(nr[0]-'0');
               else
                       x=(nr[n-2]-'0')*10+(nr[n-1]-'0');
               s=((x/20)*4)%10;
               for(j=1;j<=(x%20);j++){
                       if(j%4==0)
                               aux=4;
                       else
                               aux=j%4;
                       j1=j%10;
                       p=1;
                       for(k=0;k<aux;k++)
                               p=(p*j1)%10;
                       s=(s+p)%10;
               }
               fprintf(out,"%d\n",s);
       }
       fclose(out);
       fclose(in);
       return 0;
}