#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i = 0; i < n; i++)
#define rep2(i, x, n) for(int i = x; i <= n; i++)
#define rep3(i, x, n) for(int i = x; i >= n; i--)
#define each(e, v) for(auto &e: v)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
using ll = long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
const int MOD = 1000000007;
//const int MOD = 998244353;
const int inf = (1<<30)-1;
const ll INF = (1LL<<60)-1;
template<typename T> bool chmax(T &x, const T &y) {return (x < y)? (x = y, true) : false;};
template<typename T> bool chmin(T &x, const T &y) {return (x > y)? (x = y, true) : false;};

struct io_setup{
    io_setup(){
        ios_base::sync_with_stdio(false);
        cin.tie(NULL);
        cout << fixed << setprecision(15);
    }
} io_setup;

int query(int i, int j){
    cout << i+1 << ' ' << j+1 << endl;
    string S; cin >> S;
    return (S == "Black"? 1 : 0);
}

int main(){
    int N, M; cin >> N >> M;

    vector<vector<int>> d(N, vector<int>(N, inf));
    d[0][0] = 0;

    queue<pii> que;
    que.emplace(0, 0);

    vector<int> dx = {1, 0, -1, 0}, dy = {0, 1, 0, -1};

    while(!empty(que)){
        auto [x, y] = que.front(); que.pop();

        rep(k, 4){
            int nx = x+dx[k], ny = y+dy[k];
            if(nx < 0 || nx >= N || ny < 0 || ny >= N) continue;
            if(d[nx][ny] != inf || d[x][y]+1+(N-1-nx)+(N-1-ny) >= M) continue;

            if(query(nx, ny)){
                d[nx][ny] = d[x][y]+1;
                que.emplace(nx, ny);
            }
        }

        if(d[N-1][N-1] != inf){
            cout << "Yes" << endl;
            return 0;
        }
    }

    cout << "No" << endl;
}