#include <bits/stdc++.h>
using namespace std;
long long INF = 1e9 + 7;
long long binpow(long long x, long long n) {
  if (n == 0) {
    return 1;
  }
  if (n % 2 == 0) {
    long long a = binpow(x, n >> 1) % INF;
    return (a * a) % INF;
  } else {
    return (x * binpow(x, n - 1) % INF);
  }
}
long long C(long long n, long long k) {
  if (k == 0 or n == k) {
    return 1;
  } else {
    return C(n - 1, k - 1) + C(n - 1, k);
  }
}
void YES() { cout << "YES\n"; }
void NO() { cout << "NO\n"; }
void Yes() { cout << "Yes\n"; }
void No() { cout << "No\n"; }
bool check(long long l, long long r) {
  cout << l << " " << r << "\n";
  cout.flush();
  string s;
  cin >> s;
  return (s == "Yes");
}
void solve() {}
int32_t main() {
  long long n, k;
  cin >> n >> k;
  srand(time(0));
  long long l = 1;
  long long r = n;
  while (true) {
    l = max(1ll, l - k);
    r = min(n, r + k);
    if (r - l <= 40) {
      long long random = rand() % (r - l + 1);
      if (check(l + random, l + random)) {
        return 0;
      }
    } else {
      long long m = (l + r) >> 1;
      if (check(l, m)) {
        r = m;
      } else {
        l = m + 1;
      }
    }
  }
  return 0;
}
