import java.io.*;
import java.util.*;

public class Main {

    public static void main(String[] args) throws IOException {

        new Main().go();
    }

    PrintWriter out;
    Reader in;
    BufferedReader br;

    Main() throws IOException {

        try {

            //br = new BufferedReader( new FileReader("input.txt") );
            in = new Reader("input.txt");
            out = new PrintWriter( new BufferedWriter(new FileWriter("output.txt")) );
        }
        catch (Exception e) {

            //br = new BufferedReader( new InputStreamReader( System.in ) );
            in = new Reader();
            out = new PrintWriter( new BufferedWriter(new OutputStreamWriter(System.out)) );
        }
    }

    void go() throws IOException {

        int t = 1;
        while (t > 0) {
            solve();
            //out.println();
            t--;
        }

        out.flush();
        out.close();
    }

    int inf = 2000000000;
    int mod = 1000000007;
    double eps = 0.000000001;

    int n;
    int m;

    //ArrayList<Integer>[] g = new ArrayList[1000000];

    HashMap<Integer, Integer> map = new HashMap<>();

    void solve() throws IOException {

        int n = in.nextInt();

        int l = 1;
        int r = n-1;

        System.out.println(0);
        String t = in.nextLine();
        if (t.equals("Vacant")) {
            return;
        }

        while (l < r) {

            int x = (l+r)/2;

            System.out.println(x);
            String s = in.nextLine();
            if (s.equals("Vacant")) {
                return;
            }
            if (x%2 == 0 && s.equals(t)) {
                l = x + 1;
            }
            else
            if (x%2 == 1 && !s.equals(t)) {
                l = x + 1;
            }
            else {
                r = x - 1;
            }
        }

        System.out.println(l);
    }


    class Pair implements Comparable<Pair>{

        int a;
        int b;

        Pair(int a, int b) {

            this.a = a;
            this.b = b;
        }

        public int compareTo(Pair p) {

            if (a > p.a) return 1;
            if (a < p.a) return -1;
            if (b > p.b) return 1;
            if (b < p.b) return -1;
            return 0;
        }
    }

    class Item {

        int a;
        int b;
        int c;

        Item(int a, int b, int c) {
            this.a = a;
            this.b = b;
            this.c = c;
        }

    }

    class Reader {

        BufferedReader  br;
        StringTokenizer tok;

        Reader(String file) throws IOException {
            br = new BufferedReader( new FileReader(file) );
        }

        Reader() throws IOException {
            br = new BufferedReader( new InputStreamReader(System.in) );
        }

        String next() throws IOException {

            while (tok == null || !tok.hasMoreElements())
                tok = new StringTokenizer(br.readLine());
            return tok.nextToken();
        }

        int nextInt() throws NumberFormatException, IOException {
            return Integer.valueOf(next());
        }

        long nextLong() throws NumberFormatException, IOException {
            return Long.valueOf(next());
        }

        double nextDouble() throws NumberFormatException, IOException {
            return Double.valueOf(next());
        }


        String nextLine() throws IOException {
            return br.readLine();
        }

    }

}

Measured memory_bytes: 23740