# input
import sys
input = sys.stdin.readline
II = lambda : int(input())
MI = lambda : map(int, input().split())
LI = lambda : [int(a) for a in input().split()]
SI = lambda : input().rstrip()
LLI = lambda n : [[int(a) for a in input().split()] for _ in range(n)]
LSI = lambda n : [input().rstrip() for _ in range(n)]
MI_1 = lambda : map(lambda x:int(x)-1, input().split())
LI_1 = lambda : [int(a)-1 for a in input().split()]

def graph(n:int, m:int, dir:bool=False, index:int=-1) -> list[set[int]]:
    edge = [set() for i in range(n+1+index)]
    for _ in range(m):
        a,b = map(int, input().split())
        a += index
        b += index
        edge[a].add(b)
        if not dir:
            edge[b].add(a)
    return edge

def graph_w(n:int, m:int, dir:bool=False, index:int=-1) -> list[set[tuple]]:
    edge = [set() for i in range(n+1+index)]
    for _ in range(m):
        a,b,c = map(int, input().split())
        a += index
        b += index
        edge[a].add((b,c))
        if not dir:
            edge[b].add((a,c))
    return edge

mod = 998244353
inf = 1001001001001001001
ordalp = lambda s : ord(s)-65 if s.isupper() else ord(s)-97
ordallalp = lambda s : ord(s)-39 if s.isupper() else ord(s)-97
yes = lambda : print("Yes")
no = lambda : print("No")
yn = lambda flag : print("Yes" if flag else "No")
def acc(a:list[int]):
    sa = [0]*(len(a)+1)
    for i in range(len(a)):
        sa[i+1] = a[i] + sa[i]
    return sa

prinf = lambda ans : print(ans if ans < 1000001001001001001 else -1)
alplow = "abcdefghijklmnopqrstuvwxyz"
alpup = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
alpall = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
URDL = {'U':(-1,0), 'R':(0,1), 'D':(1,0), 'L':(0,-1)}
DIR_4 = [[-1,0],[0,1],[1,0],[0,-1]]
DIR_8 = [[-1,0],[-1,1],[0,1],[1,1],[1,0],[1,-1],[0,-1],[-1,-1]]
DIR_BISHOP = [[-1,1],[1,1],[1,-1],[-1,-1]]
prime60 = [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59]
sys.set_int_max_str_digits(0)
sys.setrecursionlimit(10**6)
# import pypyjit
# pypyjit.set_param('max_unroll_recursion=-1')

from collections import defaultdict
from heapq import heappop,heappush
from bisect import bisect_left,bisect_right
DD = defaultdict
BSL = bisect_left
BSR = bisect_right


m = II()
flag = True
edge = defaultdict(lambda: list())

tri = []
for i in range(m):
    a,b,c = MI()
    # 向きは正順でいれる
    edge[(a,b)].append(i)
    edge[(b,c)].append(i)
    edge[(a,c)].append(i)
    tri.append((a,b,c))


que = []
for e,idxs in edge.items():
    if len(idxs) >= 3:
        print("NO")
        exit()
    if len(idxs) == 1:
        que.append(e)


use = set()
dirdict = dict()

# 正方向 大きい方向とする
def solve(idx):
    idxque = [idx]
    a,b,c = tri[idx]
    while idxque:
        idx = idxque.pop()
        if idx in use:
            continue
        use.add(idx)
        a,b,c = tri[idx]
        
        # 決まっている向きと逆方向
        # print(dirdict)
        nowdir = [0,0,0]
        if (a,b) in dirdict:
            nowdir[0] = dirdict[(a,b)] * -1
        if (b,c) in dirdict:
            nowdir[1] = dirdict[(b,c)] * -1
        if (a,c) in dirdict:
            nowdir[2] = dirdict[(a,c)] # c->a方向にしておく
        
        if 1 in nowdir and -1 in nowdir:
            # print(a,b,c,nowdir)
            # print(dirdict)
            return False
        
        if 1 in nowdir: # すべてこの方向にする
            ndir = 1
        elif -1 in nowdir:
            ndir = -1
        else:
            ndir = 1
        
        if not (a,b) in dirdict:
            dirdict[(a,b)] = ndir
            if len(edge[(a,b)]) == 2:
                s,t = edge[(a,b)]
                idxque.append(s+t-idx)
                
        if not (b,c) in dirdict:
            dirdict[(b,c)] = ndir
            if len(edge[(b,c)]) == 2:
                s,t = edge[(b,c)]
                idxque.append(s+t-idx)
                
        if not (a,c) in dirdict:
            dirdict[(a,c)] = ndir*-1
            if len(edge[(a,c)]) == 2:
                s,t = edge[(a,c)]
                idxque.append(s+t-idx)
        # print(a,b,c, nowdir, dirdict)
    return True

for i in range(m):
    if i in use:
        continue
    if not solve(i): # 使っていない三角形について解いてみる
        print("NO")
        exit()

print("YES")
exit()