#include <iostream>
using namespace std;
int main()
{
    int x,y,z ;
    cout<<"z=";
    cin>>z;
    cout<<"x=";
    cin>>x;
    while (x>0)
    {
          cout<<"y=";
          cin>>y;
          if (z<y-x)
          cout<<x%10<<endl;
          else 
          cout<<y%10<<endl;
          
          x=y;
          }
          system("pause");
          return 0; 
          }