#include <bits/stdc++.h>
using namespace std;
long long int cons;
long long int check(long long int a) {
  if (a >= cons) a %= cons;
  return a;
}
long long int check2(long long int a) {
  a %= cons;
  if (a < 0) a += cons;
  return a;
}
long long int fast_check(long long int a) {
  if (a >= cons) a -= cons;
  return a;
}
long long int GCD(long long int a, long long int b) {
  while (a && b) {
    a = a % b;
    if (a != 0) b = b % a;
  }
  return a + b;
}
long long int exp(long long int a, long long int n) {
  long long int ans = 1;
  a = check(a);
  while (n) {
    if (n & 1) ans = check(ans * a);
    a = check(a * a);
    n = (n >> 1);
  }
  return ans;
}
void print_pair(pair<int, int> p) {
  cout << p.first << " " << p.second << endl;
}
long long int nc2(long long int a) { return (a * (a - 1)) / 2; }
const int N = 1e5 + 10;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cons = 1e9 + 7;
  long long int n, k;
  cin >> n >> k;
  srand(time(NULL));
  int h;
  long long int lef = 1, rig = n;
  long long int one = 1;
  int coun = 0;
  while (lef <= rig) {
    coun++;
    assert(coun <= 4500);
    if (lef == rig) {
      cout << lef << " " << rig << endl;
      return 0;
    }
    if (rig - lef <= 4 * k + 1) {
      long long int temp = rig - lef + 1;
      long long int rr = rand() % temp;
      long long int mid = lef + rr;
      cout << mid << " " << mid << endl;
      string s;
      cin >> s;
      if (s == "Yes") return 0;
      lef = max(one, lef - k);
      rig = min(n, rig + k);
      continue;
    }
    long long int mid = (lef + rig) / 2;
    cout << lef << " " << mid << endl;
    string s;
    cin >> s;
    if (s == "Yes") {
      if (lef == mid) {
        return 0;
      }
      lef = max(one, lef - k);
      rig = min(n, mid + k);
    } else {
      lef = max(one, mid - k);
      rig = min(n, rig + k);
    }
  }
  return 0;
}
