#include <bits/stdc++.h>
using namespace std;
long long N;
int K;
pair<long long, long long> expand(pair<long long, long long> p) {
  return pair<long long, long long>(max(1ll, p.first - K),
                                    min(N, p.second + K));
}
bool query(pair<long long, long long> p) {
  printf("%lld %lld\n", p.first, p.second);
  fflush(stdout);
  char tmp[99];
  scanf("%s", tmp);
  if (tmp[0] == 'Y') {
    return true;
  } else if (tmp[0] == 'N') {
    return false;
  } else {
    exit(0);
    return false;
  }
}
int main() {
  scanf("%lld%d", &N, &K);
  srand(420);
  pair<long long, long long> p = {1, N};
  while (true) {
    if (p.second - p.first + 1 <= 6 * K) {
      long long x = p.first + rand() % (p.second - p.first + 1);
      if (query(pair<long long, long long>(x, x))) {
        return 0;
      }
      p = expand(p);
    } else {
      long long mi = (p.first + p.second) / 2;
      pair<long long, long long> l = {p.first, mi}, r = {mi + 1, p.second};
      if (query(l)) {
        if (l.first == l.second) {
          return 0;
        }
        p = expand(l);
      } else {
        p = expand(r);
      }
    }
  }
}
