import collections,sys,math,functools,operator,itertools,bisect,heapq,decimal,string,time,random
#https://github.com/shakayami/ACL-for-python/blob/master/two_sat.py
def two_sat(n,clause):
    answer=[0]*n
    edges=[]
    N=2*n
    for s in clause:
        i,f,j,g=s
        edges.append((2*i+(0 if f else 1),2*j+(1 if g else 0)))
        edges.append((2*j+(0 if g else 1),2*i+(1 if f else 0)))
    M=len(edges)
    start=[0]*(N+1)
    elist=[0]*M
    for e in edges:
        start[e[0]+1]+=1
    for i in range(1,N+1):
        start[i]+=start[i-1]
    counter=start[:]
    for e in edges:
        elist[counter[e[0]]]=e[1]
        counter[e[0]]+=1
    visited=[]
    low=[0]*N
    Ord=[-1]*N
    ids=[0]*N
    NG=[0,0]
    def dfs(v):
        stack=[(v,-1,0),(v,-1,1)]
        while stack:
            v,bef,t=stack.pop()
            if t:
                if bef!=-1 and Ord[v]!=-1:
                    low[bef]=min(low[bef],Ord[v])
                    stack.pop()
                    continue
                low[v]=NG[0]
                Ord[v]=NG[0]
                NG[0]+=1
                visited.append(v)
                for i in range(start[v],start[v+1]):
                    to=elist[i]
                    if Ord[to]==-1:
                        stack.append((to,v,0))
                        stack.append((to,v,1))
                    else:
                        low[v]=min(low[v],Ord[to])
            else:
                if low[v]==Ord[v]:
                    while(True):
                        u=visited.pop()
                        Ord[u]=N
                        ids[u]=NG[1]
                        if u==v:
                            break
                    NG[1]+=1
                low[bef]=min(low[bef],low[v])
    for i in range(N):
        if Ord[i]==-1:
            dfs(i)
    for i in range(N):
        ids[i]=NG[1]-1-ids[i]
    for i in range(n):
        if ids[2*i]==ids[2*i+1]:
            return None
        answer[i]=(ids[2*i]<ids[2*i+1])
    return answer
#sys.setrecursionlimit(10**9)
#sys.set_int_max_str_digits(0)
input = sys.stdin.readline
n = int(input())
#alist = list(map(int,input().split()))
#alist = []
#s = input()
#n,m = map(int,input().split())
#for i in range(n):
#    alist.append(list(map(int,input().split())))
co = collections.defaultdict(list)
x = 10**9
for i in range(n):
    a,b,c = map(int,input().split())
    co[a*x+b].append(i)
    co[b*x+c].append(i)
    co[a*x+c].append(~i)
cl = []
for i in co:
    if len(co[i]) >= 3:
        exit(print('NO'))
    if len(co[i]) == 2:
        z = 0
        if co[i][0] < 0:
            co[i][0] = ~co[i][0]
            z ^= 1
        if co[i][1] < 0:
            co[i][1] = ~co[i][1]
            z ^= 1
        if z == 0:
            cl.append((co[i][0],True,co[i][1],False))
            cl.append((co[i][0],False,co[i][1],True))
        else:
            cl.append((co[i][0],True,co[i][1],True))
            cl.append((co[i][0],False,co[i][1],False))

ans = two_sat(n,cl)
if ans != None:
    print('YES')
else:
    print('NO')