#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e18;
const long long mod = 1e17 + 7;
const long long N = 2e5 + 5;
long long n, k, l, r, m, f = 0;
string s;
void sh() {
  while (r - l > max(20LL, 5 * k)) {
    m = (l + r) / 2;
    cout << l << " " << m << endl;
    cout.flush();
    cin >> s;
    if (s[0] == 'Y') {
      l = l - k;
      r = m + k;
    } else {
      l = m - k;
      r = r + k;
    }
    l = max(l, 1LL);
    r = min(r, n);
  }
}
void guess() {
  long long x = r - l + 1;
  long long kx = rand();
  kx %= x;
  kx += l;
  cout << kx << " " << kx << endl;
  cout.flush();
  cin >> s;
  if (s[0] == 'Y') f = 1;
}
int main() {
  ios_base::sync_with_stdio(false);
  srand(time(NULL));
  cin >> n >> k;
  l = 1;
  r = n;
  while (1) {
    sh();
    long long ix = 3;
    while (ix--) {
      guess();
      if (f) return 0;
      l -= k;
      r += k;
      l = max(l, 1LL);
      r = min(n, r);
    }
  }
}
