#include <bits/stdc++.h>
using namespace std;
long long gcd(long long a, long long b) {
  if (a == 0LL) return b;
  return gcd(b, a % b);
}
void solve(long long n, long long l, long long r, long long k) {
  long long len = r - l + 1LL, temp;
  string s;
  if (len <= (k + 1LL) * 6LL) {
    temp = l + (rand() % len);
    cout << temp << " " << temp << "\n";
    fflush(stdout);
    cin >> s;
    if (s == "Yes") return;
    l = l - k;
    r = r + k;
    l = max(1LL, l);
    r = min(r, n);
    solve(n, l, r, k);
    return;
  }
  long long l1, r1, l2, r2, mid;
  mid = (l + r) / 2LL;
  l1 = l - k;
  r1 = mid;
  l1 = max(l1, 1LL);
  r1 = min(r1, n);
  cout << l1 << " " << r1 << "\n";
  fflush(stdout);
  cin >> s;
  if (s == "Yes") {
    if (l1 == r1) return;
    l1 -= k;
    r1 += k;
    l1 = max(l1, 1LL);
    r1 = min(r1, n);
    solve(n, l1, r1, k);
  } else {
    l2 = r1 + 1LL - k;
    r2 = max(r, r1) + 2LL * k;
    l2 = max(l2, 1LL);
    r2 = min(r2, n);
    solve(n, l2, r2, k);
  }
  return;
}
int main() {
  ios::sync_with_stdio(false);
  srand(time(NULL));
  long long n, k;
  cin >> n >> k;
  solve(n, 1, n, k);
  return 0;
}
