#include <iostream>
#include <algorithm>
#include <queue>
#include <string>
using namespace std;

int r[509][509], dx[4] = { 1, 0, -1, 0 }, dy[4] = { 0, 1, 0, -1 };
queue<pair<int, int> > q;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m; cin >> n >> m;
    q.push(make_pair(1, 1));
    r[1][1] = 1;
    while (!q.empty()) {
        int y = q.front().first, x = q.front().second; q.pop();
        for (int i = 0; i < 4; i++) {
            int tx = x + dx[i], ty = y + dy[i];
            if (tx < 1 || tx > n || ty < 1 || ty > n || r[ty][tx]) continue;
            cout << ty << " " << tx << endl;
            string s; cin >> s;
            if (s[0] == 'B') {
                r[ty][tx] = 1;
                q.push(make_pair(ty, tx));
            }
            else
                r[ty][tx] = -1;
        }
    }
    if (r[n][n] == 1) cout << "Yes" << endl;
    else cout << "No" << endl;
    return 0;
}