from collections import deque

N, M = map(int, input().split())
grid = [[None]*N for _ in range(N)]
grid[0][0] = True
grid[-1][-1] = True
M -= 2

q = deque()
q.append((0, 0))
move = [(-1, 0), (1, 0), (0, 1), (0, -1)]

def ques(y, x):
    print(x+1, y+1)
    s = input()
    if s == 'Black':
        return True
    else:
        return False


flag = False
qs = 0
while q and M:
    y, x = q.popleft()
    for dy, dx in move:
        ny, nx = dy+y, dx+x
        if 0 <= ny < N and 0 <= nx < N and grid[nx][ny] is None:
            if nx == ny == N-1:
                flag = True
                q = deque()
                break
            if ques(ny, nx):
                grid[ny][nx] = True
                q.append((ny, nx))
                qs += 1
                if qs == 3000:
                    q = deque()
                    break
                M -= 1
            else:
                grid[ny][nx] = False


if flag:
    print('Yes')
else:
    print('No')