#include <algorithm>
#include <array>
#include <cmath>
#include <cstdio>
#include <deque>
#include <iomanip>
#include <iostream>
#include <numeric>
#include <optional>
#include <queue>
#include <sstream>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

int main() {
    int32_t t;
    cin >> t;
    for (auto i = 0; i < t; ++i) {
        string s;
        cin >> s;
        while (s.size() > 1) {
            string ss = "";
            for (auto j = 0; j < s.size() - 1; ++j) {
                auto x = (s[j] - '0') + (s[j + 1] - '0');
                if (x >= 10)
                    x = 1 + x % 10;
                ss += to_string(x);
            }
            s = ss;
        }
        cout << s << endl;
    }
    return 0;
}