R,O=range,print
J=lambda:list(map(int,input().split()))
M,*_=J()
ABC=[J()for m in R(M)]
def hash(A,B):return A|B<<30
edge_num={}
vertex=[]
edge=[[]for m in R(M)]
for m,ABCm in zip(R(M),ABC):
	for i in R(2):
		for j in R(i+1,3):
			e=hash(ABCm[i],ABCm[j])
			if e in edge_num:
				v=vertex[edge_num[e]]
				v+[m]
				if len(v)>2:exit(O("NO"))
				else:edge[m]+=[v[0]];edge[v[0]]+=[m]
			else:size=len(edge_num);edge_num[e]=size;vertex+=[[m]]
dfs=[0]*M
sigma=set()
for m in R(M):
	if dfs[m]:continue
	dfs[m],stack=1,[m]
	while stack:
		n=stack.pop();ABCn=ABC[n];
		positive=all(not hash(ABCn[i],ABCn[(i+1)%3]) in sigma for i in R(3))
		negative=all(not hash(ABCn[(i+1)%3],ABCn[i]) in sigma for i in R(3))
		if not positive and not negative:exit(O("NO"))
		if positive:
			for i in R(3):sigma.add(hash(ABCn[i],ABCn[(i+1)%3]))
		else:
			for i in R(3):sigma.add(hash(ABCn[(i+1)%3],ABCn[i]))
		for l in edge[n]:
			if not dfs[l]:dfs[l]=1;stack+=[l]
print("YES")