#include <iostream>
#include <algorithm>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <string.h>
#include <vector>
#include <queue>
#include <cmath>
#include <bitset>
#include <complex>
#include <functional>
#include <numeric>
#include <iomanip>

// output
#define SPBR(w, n) std::cout<<(w + 1 == n ? '\n' : ' ');
#define YES cout << "YES" << endl
#define Yes cout << "Yes" << endl
#define NO cout << "NO" << endl
#define No cout << "No" << endl
// utility
#define ALL(i) (i).begin(), (i).end()
#define FOR(i, a, n) for(int i=(a);i<(n);++i)
#define RFOR(i, a, n) for(int i=(n)-1;i>=(a);--i)
#define REP(i, n) for(int i=0;i<int(n);++i)
#define RREP(i, n) for(int i=int(n)-1;i>=0;--i)
#define IN(a, x, b) (a<=x && x<b)
#define OUT(a, x, b) (x<a || b<=x)
template<class T> inline T chmax(T & a, const T b) { return a = (a < b) ? b : a; }
template<class T> inline T chmin(T& a, const T b) { return a = (a > b) ? b : a; }

// type/const
#define int ll
using ll = long long;
using ull = unsigned long long;
using ld = long double;
const int MOD = 1000000007;
/* const int MOD = 998244353; */
const int INF = 1e18;
const double PI = acos(-1);

using namespace std;


signed main() {
  int N;
  cin >> N;

  cout << 0 << "\n";
  string p;
  int pos = 0;
  cin >> p;
  if(p[0] == 'V'){
    cout << 0 << "\n";
    return 0;
  }

  int le = N+1;
  int ri = 0;
  while(1){
    int mid = (ri+le)/2;
    cout << mid << "\n";
    string s;
    cin >> s;
    if(s[0] == 'V'){
      return 0;
    }

    if(abs(pos-mid)%2 == 0){
      if(s == p) ri = mid;
      else le = mid;
    }else{
      if(s != p) ri = mid;
      else le = mid;
    }
  }

  return 0;
}
#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
using namespace std;
using ll = long long;
using P = pair<int,int>;

int main() {
  int n;
  scanf("%d", &n);
  int l = 0, r = n;
  printf("%d\n", l);
  fflush(stdout);
  string sl;
  cin >> sl;
  while (sl != "Vacant") {
    int m = (l + r) / 2;
    printf("%d\n", m);
    fflush(stdout);
    string sm;
    cin >> sm;
    if (sm == "Vacant" || l % 2 == m % 2 && sl == sm || l % 2 != m % 2 && sl != sm) {
      l = m;
      sl = sm;
    } else {
      r = m;
    }
  }
  printf("%d\n", l);
  fflush(stdout);
  return 0;
}