#include <bits/stdc++.h>
template<class T> inline bool chmin(T&a, T b){if(a > b){a = b; return true;}else{return false;}}
template<class T> inline bool chmax(T&a, T b){if(a < b){a = b; return true;}else{return false;}}
#define ll long long
#define double long double
#define rep(i,n) for(int i=0;i<(n);i++)
#define REP(i,n) for(int i=1;i<=(n);i++)
#define mod (ll)(1e9+7)
#define inf (ll)(3e18+7)
#define eps (double)(1e-9)
#define pi (double) acos(-1)
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
using namespace std;

int ask(int a, int b){
    string ret;
    cout << a+1 << " " << b+1 << endl;
    cin >> ret;
    assert(ret != "-1");
    return (ret == "Black" ? 1 : 0);
}

int dx[4] = {0, 0, 1, -1};
int dy[4] = {1, -1, 0, 0};

int main(){
    int n, m;
    cin >> n >> m;
    vector<vector<int>> dp(n, vector<int>(n, -1));
    bool ans = false;
    queue<pair<int, int>> que;
    que.push({0, 0});
    dp[0][0] = true;
    while(!que.empty()){
        pair<int, int> p = que.front();
        que.pop();
        int x = p.first, y = p.second;
        dp[x][y] = 1;
        rep(i, 4){
            int nx = x + dx[i];
            int ny = y + dy[i];
            if(nx < 0 || nx >= n || ny < 0 || ny >= n)continue;
            if(dp[nx][ny] != -1)continue;
            if(ask(nx, ny)){
                dp[nx][ny] = 1;
                que.push({nx, ny});
            }else{
                dp[nx][ny] = 0;
            }
        }
    }
    cout << (dp[n-1][n-1] == 1 ? "Yes" : "No") << endl;
}