#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int uc[101]={0,1,5,2,8,3,9,2,8,7,7,8,4,7,3,8,4,1,5,4,4,5,9,6,2,7,3,6,2,1,1,2,8,1,7,2,8,5,9,8,8,9,3,0,6,1,7,0,6,5,5,6,2,5,1,6,2,9,3,2,2,3,7,4,0,5,1,4,0,9,9,0,6,9,5,0,6,3,7,6,6,7,1,8,4,9,5,8,4,3,3,4,0,3,9,4,0,7,1,0,0};
int cifra(int x)
{
    unsigned long long int i,s=1;
    for (i=1; i<=x; i++)
    {
       s*=x ;
    }
    return s % 10;
}
int main()
{
    FILE *pf,*pg;
    pf=fopen("cifra.in","r");
    pg=fopen("cifra.out","w");

    int n,i;
    char c[101];
    fscanf(pf,"%d",&n);
    /*for (i=1; i<=100; i++)
        uc[i]=(uc[i-1]+cifra(i)) % 10;
    for (i=1; i<=100; i++)
        printf("%d ",uc[i]);*/
    while (n>0)
    {
        fscanf(pf,"%s",c);
        if (strlen(c)==1)
            fprintf(pg,"%d\n",uc[c[0]-'0']);
        else
            fprintf(pg,"%d\n",uc[(c[strlen(c)-2]-'0')*10+c[strlen(c)-1]-'0']);
        n--;
    }
    return 0;
}