#include <algorithm>
#include <cstdio>
#include <iostream>
#include <iomanip>
#include <vector>
#include <map>
#include <set>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cstring>
#include <string>
#include <sstream>
#include <queue>
#include <bitset>
#include <fstream>
#include <stack>
#include <deque>
#include <utility>
#include <numeric>

using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
const int N = 50;
const int LIM = 5e5;

string s[N];
bool used[LIM];

int main() {
    freopen("input.txt", "r", stdin);
    ios_base::sync_with_stdio(false);
    int n;
    cin >> n;
    cout << 2 << "\n";
    cout.flush();
    cin >> s[1];
    if (s[1] == "OK") return 0;
    for (int i = 2; i <= 41; i++) {
        cout << 2 << "\n";
        cout.flush();
        cin >> s[i];
    }
    for (int i = 2; i <= n; i++) {
        if (used[i]) continue;
        for (ll f = 1LL * i * i; f <= n; f += i) used[f] = true;
    }
    for (int t = n; t >= 3; t--) {
        if (used[t]) continue;
        int l = 1, r = t - 1;
        for (int i = 1; i <= 41; i++) {
            int m = (l + r) / 2;
            if (s[i] == ">") r = m; else l = m + 1;
            if (l == r) break;
        }
        if (l >= t) continue;
        int x0 = l, x = l, nom;
        for (int i = 1; i <= 41; i++) if (s[i] == "<") {
            nom = i + 1;
            break;
        }
        else x *= 2;
        l = 1, r = t - 1;
        for (int i = nom; i <= 41; i++) {
            int m = (l + r) / 2;
            if (s[i] == ">") r = m; else l = m + 1;
            if (l == r) break;
        }
        if (l >= t) continue;
        int p = 2 * x - l;
        if (p != t) continue;
        bool ok = true;
        for (int i = 1; i <= 41; i++) {
            x = x0 * 2;
            if (x >= p) x -= p;
            if ((x > x0 && s[i] == "<") || (x < x0 && s[i] == ">")) {
                ok = false;
                break;
            }
            x0 = x;
        }
        if (!ok) continue;
        cout << p << "\n";
        cout.flush();
        cin >> s[42];
        break;
    }
    return 0;
}