import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Stack;

public class Main2 {
    public static void main(String[] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        String str = in.readLine();
        int n = Integer.parseInt(str);
        String[] input = new String[n];
        int[] numbers = new int[n];
        for (int i = 0; i < n; i++) {
            input[i] = in.readLine();
            numbers[i] = Integer.parseInt(input[i].replaceAll("[^0-9]", ""));
        }
        Stack<Integer> nested = new Stack<>();
        StringBuilder stringBuilder = new StringBuilder();

        for (int i = 0; i < n; i++) {
            if (nested.size()==0) {
                stringBuilder.append(String.format("<%s>\n", input[i]));
                nested.push(i);
                continue;
            }
            if (numbers[i] > numbers[i - 1]) {
                for (int j = 0; j < nested.size(); j++) stringBuilder.append(" ");
                stringBuilder.append(String.format("<%s>\n", input[i]));
                nested.push(i);
            } else {
                while (nested.size()!=0 && numbers[nested.peek()] >= numbers[i]) {
                    for (int h = 0; h < nested.size()-1; h++) stringBuilder.append(" ");
                    stringBuilder.append(String.format("</%s>\n", input[nested.pop()]));
                }

                for (int j = 0; j < nested.size(); j++) stringBuilder.append(" ");
                stringBuilder.append(String.format("<%s>\n", input[i]));
                nested.push(i);
            }
        }
        while (!nested.isEmpty()) {
            for (int h = 0; h < nested.size()-1; h++) stringBuilder.append(" ");
            stringBuilder.append(String.format("</%s>\n", input[nested.pop()]));
        }

        System.out.println(stringBuilder.toString());
    }
}