def scc(N, G):
    order = []
    used = [False]*N
    group = [None]*N
    RG = [[] for _ in range(N)]
    for i in range(N):
        for j in G[i]:
            RG[j].append(i)
    
    def dfs(pos):
        stack = [(1, pos), (0, pos)]
        while stack:
            t, pos = stack.pop()
            if t == 0:
                if used[pos]:
                    stack.pop()
                    continue
                used[pos] = True
                for npos in G[pos]:
                    if not used[npos]:
                        stack.append((1, npos))
                        stack.append((0, npos))
            else:
                order.append(pos)

    def rdfs(pos, col):
        stack = [pos]
        group[pos] = col
        used[pos] = True
        while stack:
            pos = stack.pop()
            for npos in RG[pos]:
                if not used[npos]:
                    used[npos] = True
                    group[npos] = col
                    stack.append(npos)
                    
    for i in range(N):
        if not used[i]:
            dfs(i)
    used = [False]*N
    label = 0
    for s in reversed(order):
        if not used[s]:
            rdfs(s, label)
            label += 1
    return label, group

class Two_SAT:
    def __init__(self, n):
        self.n = n
        self.G = [[] for _ in range(2 * n)]
    
    # a V B
    # pos_i = True -> a = i
    # pos_i = False -> a = ¬i
    def add_edge(self, i, pos_i, j, pos_j):
        i0 = i
        i1 = i + self.n
        if not pos_i:
            i0, i1 = i1, i0
        j0 = j
        j1 = j + self.n
        if not pos_j:
            j0, j1 = j1, j0
        self.G[i1].append(j0)
        self.G[j1].append(i0)
            
    def const(self):
        _, self.group = scc(2 * self.n, self.G)
    
    def check(self):
        for i in range(self.n):
            if self.group[i] == self.group[i + self.n]:
                return False
        return True
        
    def assign(self):
        ret = [False] * self.n
        for i in range(self.n):
            if self.group[i] > self.group[i + self.n]:
                ret[i] = True
        return ret

n = int(input())
RC = [list(map(int, input().split())) for _ in range(n)]
TS = Two_SAT(n)

for i in range(n):
    r0, c0, r1, c1 = RC[i]
    for j in range(i + 1, n):
        r2, c2, r3, c3 = RC[j]
        for ii, p0 in enumerate([(r0, c0), (r1, c1)]):
            for jj, p1 in enumerate([(r2, c2), (r3, c3)]):
                if p0 == p1:
                    TS.add_edge(i, ii, j, jj)

TS.const()
if TS.check():
    print("YES")
else:
    print("NO")