#include <cstdio>
#include <algorithm>
#include <iostream>
#include <vector>
#include <iomanip>
#include <typeinfo>
#include <string>
using namespace std;


int main(void){

  int T,i,j,k;
  string S;
  int s[1010100];
  int t;
  cin>>T;
  char c;
  getchar();

  while(T>=1){
    k=0;
    while((c=getchar())!='\n'){
      s[k]=c-'0';
      k++;
    }
    for(i=0;i<k-1;i++){
      for(j=0;j<k-1-i;j++){
        s[j]=s[j]+s[j+1];
        if(s[j]>9) s[j]-=9;
      }
    }
    cout<<s[0]<<endl;
    T--;
  }

  return 0;
}