#include <bits/stdc++.h>
using namespace std;
string s;
long long n, k, R, L;
void dif() {
  L -= k;
  if (L < 1) L = 1;
  R += k;
  if (R > n) R = n;
}
bool go(long long l, long long r) {
  cout << l << " " << r << endl;
  cin >> s;
  return (s == "Yes");
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  srand(time(0));
  cin >> n >> k;
  L = 1;
  R = n;
  while (true) {
    if (R - L + 1 > 50) {
      long long M = (L + R) / 2;
      if (go(L, M))
        R = M;
      else
        L = M + 1;
      dif();
    } else {
      int len = R - L + 1;
      long long x = L + (rand() % len);
      if (go(x, x)) return 0;
      dif();
    }
  }
  return 0;
}
