public class Solution
{
    public static void main(String[] args) {
        readData();
    }

    public static void readData() {
        BufferedReader reader = new BufferedReader (new InputStreamReader(System.in));
        ArrayList list = new ArrayList();
        try{
        while (true){
                String fig = reader.readLine();
                int nFig = Integer.parseInt(fig);
                list.add(nFig);
            }
        }
        catch (Exception e){
            for (int i = 0; i < list.length; i++){
                System.out.println (i);
            }
        }
    }
}