#include <bits/stdc++.h>
using namespace std;

// macros
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define MIN(a,b) (a>b?b:a)
#define MAX(a,b) (a>b?a:b)
#define INT_IN(a) int a; cin >> a
#define STR_IN(s) string s; cin >> s
#define PRINTLN(s) cout << s << endl
#define PRINTDOUBLELN(s) cout << setprecision(12) << (s) << endl;

// util functions
template<class T> inline T sqr(T x) {return x*x;}

inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}

template <typename T>inline T max(vector<T> v){T max=v[0]; FOR(i, 1, v.size())max=MAX(v[i], max); return max;}
template <typename T>inline T min(vector<T> v){T min=v[0]; FOR(i, 1, v.size())min=MIN(v[i], min); return min;}
template <typename T>inline vector<T> concat(vector<T> a, vector<T> b){vector<T> ab; ab.reserve(a.size()+b.size());ab.insert(ab.end(),a.begin(),a.end());ab.insert(ab.end(),b.begin(),b.end());return ab;}

// types
typedef long long LL;

// consts
const double EPS = 1e-10;
const double PI  = acos(-1.0);

//debug
#define dump(x)  #x << " = " << (x) << endl
#define debug(x) #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl

int combination(int n, int r){
    if(n == r) return 1;
    if((r << 1) > n) r = n - r;
    if(r == 0) return 1;

    int res = n;
    FOR(i, 2, r + 1){
        res *= n - i + 1;
        res /= i;
    }
    return res;
}

int main(){
    INT_IN(T);
    REP(i, T){
        STR_IN(S);
        int l = S.length();
        if(l == 1){
            PRINTLN(S);
        }else{
            vector<int> iS;
            REP(j, l){
                iS.push_back(S[j] - '0');
            }
            while(l-- > 1){
                vector<int> niS;
                REP(j, l){
                    int s = iS[j] + iS[j + 1];
                    if(s > 9)s -= 9;
                    cerr << debug(s);
                    niS.push_back(s);
                }
                iS = niS;
            }
            PRINTLN(iS[0]);
        }
    }
    return 0;
}