from collections import *

N, M = map(int, input().split())
Q = deque()
Q.append((0, 0))
dx = [1, 0, -1, 0]
dy = [0, 1, 0, -1]
seen = [[0] * N for _ in range(N)]
seen[0][0] = 1

def query(x, y):
    print(x, y, flush=True)
    return input() == "Black"

while Q:
    px, py = Q.popleft()
    for k in range(4):
        x = px + dx[k]
        y = py + dy[k]
        if x < 0 or x > N - 1 or y < 0 or y > N - 1:
            continue
        if seen[x][y]:
            continue
        seen[x][y] = 1
        if query(x, y):
            Q.append((x, y))
            
print("Yes") if seen[N-1][N-1] else print("No")