g=[input() for _ in range(3)]
def check(i,j):
    f=True
    dy=[1,0,-1,0];dx=[0,1,0,-1]
    for k in range(4):
        y=i+dy[k];x=j+dx[k]
        if 0<=y<3 and 0<=x<3:
            if g[i][j]==g[y][x]:
                f=False
    return f
ans=True
for i in range(3):
    for j in range(3):
        ans=ans and check(i,j)
print('Yes' if ans else 'No')