n = int(input())
xy = [[int(i) for i in input().split()] for j in range(n)]
a = [2,8]
b = [3,9]
c = [7,9]

for i in range(n):
    x1,y1,x2,y2 = xy[i]
    xy1 = [x1,y1]
    xy2 = [x2,y2]
    if xy1 == a:
        a = xy2
    elif xy1 == b:
        b = xy2
    elif xy1 == c:
        c = xy2

if a == [5,8] and b == [4,8] and c == [6,8]:
    print("YES")
else:
    print("NO")