N,M=map(int,input().split())
queue=[(0,0)]
seen=[[False]*N for x in range(N)]
seen[0][0]=True
while queue:
    x,y=queue.pop()
    for dx,dy in ((0,1),(1,0),(0,-1),(-1,0)):
        xx=x+dx
        yy=y+dy
        if (xx,yy)==(N-1,N-1):
            print("Yes")
            exit()
        if 0<=xx<N and 0<=yy<N and not seen[xx][yy]:
            print(xx+1,yy+1)
            S=input()
            if S=="Black":
                queue.append((xx,yy))
            seen[xx][yy]=True