#include <cstdio>
#include <cstring>
using namespace std;

int T;
char N[102];
int result[101];

void computeResult()
{
    int n,i,j;

    for(i=1;i<=100;++i){
        n=1;
        for(j=1;j<=i;++j)
            n=(n*(i%10))%10;
        result[i]=(result[i-1]+n)%10;
    }
}

int main()
{
    freopen("cifra.in","r",stdin);
    freopen("cifra.out","w",stdout);

    computeResult();
    scanf("%d", &T);

    for(int i=1;i<=T;++i){
        scanf("%s", &N);

        int lgn=strlen(N);
        int index=N[lgn-1]-'0';

        if(lgn>1)
            index=(N[lgn-2]-'0')*10+index;
        printf("%d\n", result[index]);
    }
    return 0;
}