from itertools import *
from bisect import *
from math import *
from collections import *
from heapq import *
from random import *
import numpy as np
import sys

sys.setrecursionlimit(10 ** 6)
int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.readline())
def MI(): return map(int, sys.stdin.readline().split())
def MI1(): return map(int1, sys.stdin.readline().split())
def MF(): return map(float, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LF(): return list(map(float, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
dij=[(1,0),(0,1),(-1,0),(0,-1)]

def main():
    def check(aa):
        for a0,a1,a2 in zip(aa,aa[1:],aa[2:]):
            if a0==a1 or a1==a2 or a0==a2:return False
            if a0<=a1<=a2:return False
        return True

    dd=LI()
    dd.sort()
    for i in range(5):
        if dd[i]==dd[i+1]==dd[i+2]:
            print("NO")
            exit()
    small=[]
    big=[]
    si=-1
    while len(small)<3:
        si+=1
        if si!=0 and dd[si]==dd[si-1]:
            big.append(dd[si])
            continue
        small.append(dd[si])
    for i in range(si+1,7):
        big.append(dd[i])

    aa=[]
    for i in range(4):
        aa.append(big[i])
        if i==3:break
        aa.append(small[i])
    if check(aa):
        print("YES")
        exit()

    small=[]
    big=[]
    si=-1
    while len(small)<4:
        si+=1
        if si!=0 and dd[si]==dd[si-1]:
            big.append(dd[si])
            continue
        small.append(dd[si])
    for i in range(si+1,7):
        big.append(dd[i])

    aa=[]
    for i in range(4):
        aa.append(small[i])
        if i==3:break
        aa.append(big[i])
    if check(aa):
        print("YES")
        exit()
    print("NO")

main()