#include <fstream>
#include <cstring>
using namespace std;
ifstream in("cifra.in");
ofstream out("cifra.out");
int T, n, len, a[102];
char sir[102];

int main()
{
    in >> T;
    for(int i = 1; i < 100; ++i)
    {
        a[i] = i;
        for(int j = 2; j <= i; ++j)
            a[i] = (a[i]*i)%10;
        a[i] = (a[i]+a[i-1])%10;
    }
    while(T--)
    {
        in.get();
        in.get(sir, 102);
        len = strlen(sir);
        if(len == 1) out << a[sir[len-1]-'0'] << '\n';
        else out << a[(sir[len-2]-'0')*10 + (sir[len-1]-'0')] << '\n';
    }
    in.close(), out.close();
    return 0;
}
/*
0 5 0 5     0   25  50  75
1 1 1 1
5 0 5 0     2   27  52  77
2 2 2 2
8 3 8 3     4   29  54  79
3 3 3 3
9 4 9 4     6   31  56  81
2 2 2 2
8 3 8 3     8   33  58  83
7 7 7 7
7 2 7 2     10  35  60  85
8 8 8 8
4 9 4 9     12  37  62  87
7 7 7 7
3 8 3 8     14  39  64  89
8 8 8 8
4 9 4 9     16  41  66  91
1 1 1 1
5 0 5 0     18  43  68  93
4 4 4 4
4 9 4 9     20  45  70  95
5 5 5 5
9 4 9 4     22  47  72  97
6 6 6 6
2 7 2 7     24  49  74  99
7 7 7 7
*/