#include <bits/stdc++.h>
using namespace std;
using lli = long long;
using ld = long double;
mt19937 rnd(time(nullptr));
bool Ask(lli l, lli r) {
  cout << l << ' ' << r << endl;
  string ans;
  cin >> ans;
  return (ans[0] == 'Y');
}
inline void Solve() {
  lli n = 0, k = 0;
  cin >> n >> k;
  lli l = 1, r = n;
  while (true) {
    if (r - l + 1 <= 4LL * k + 9) {
      lli id = l + rnd() % (r - l + 1);
      if (Ask(id, id)) exit(0);
      l = max(1LL, l - k);
      r = min(n, r + k);
    } else {
      lli m = (l + r) / 2;
      if (Ask(l, m)) {
        l = max(1LL, l - k);
        r = min(n, m + k);
      } else {
        l = max(1LL, m - k + 1);
        r = min(n, r + k);
      }
    }
  }
}
signed main() {
  Solve();
  return 0;
}
