#include <bits/stdc++.h>
using namespace std;
long long n, k;
string ans;
int main() {
  cin >> n >> k;
  srand(time(0));
  long long l = 1LL;
  long long r = n;
  while (true) {
    while (r - l + 1 > 6 * k + 10) {
      long long mid = (l + r) / 2;
      cout << mid << ' ' << r << endl;
      cin >> ans;
      if (ans == "Bad") return 0;
      if (ans == "Yes")
        l = mid - k, r += k;
      else
        l -= k, r = mid + k;
      l = max(l, 1LL);
      r = min(r, n);
    }
    long long kk = l + (rand() % (r - l + 1));
    cout << kk << ' ' << kk << endl;
    cin >> ans;
    l -= k;
    r += k;
    l = max(l, 1LL);
    r = min(r, n);
    if (ans == "Yes") return 0;
    if (ans == "Bad") return 0;
  }
}
