#include <iostream>
#include <string>
using namespace std;

int main() {
  int t;
  cin >> t;

  string s, tmp;
  for (int i=0; i<t; i++) {
    cin >> s;

    while (s.size()>1) {
      for (int j=1; j<s.size(); j++) {
        int t;
        t=s[j]-'0'+s[j-1]-'0';

        if (t>=10) t=1+(t%10);
        tmp+=(t+'0');
      }
      s=tmp;
      tmp="";
    }
    
    cout << s << endl;
  }

}