public class Solution {
      public static void main(String[] args) throws IOException
    {
        String fname;
        Scanner scan = new Scanner(System.in);
        fname = scan.nextLine();
        FileInputStream in = new FileInputStream(fname);
        int temp=in.read();
        int c=0;
        while(in.available()>0)
        {
            int data=in.read();
            if(data==temp){
                temp=data;
            }
            System.out.print(" "+temp);
        }
        in.close();

}

}