import sys
input = sys.stdin.readline

def Nand(a, b):
	if(a == 1 and b == 1):
		return 0
	return 1

a = list(map(int, input().split()))
lis = sorted(set(a))
ans = False
for bit in range(1 << len(lis)):
	var = {}
	for i, k in enumerate(lis):
		var[k] = (bit >> i) & 1
	if(Nand(Nand(Nand(var[a[0]], var[a[1]]), var[a[2]]), Nand(Nand(var[a[3]], var[a[4]]), var[a[5]])) == 1):
		ans = True
		break

if(ans):
	print("YES")
else:
	print("NO")