D = [int(i) for i in input().split()]
L = len(D)
used = [False for i in range(L)]
S = [-1 for i in range(L)]
def dfs(n):
	if n == L:
		for i in range(L - 2):
			if (max(S[i:i + 2]) == S[i + 1] or min(S[i:i + 2]) == S[i + 1]) and S[i] < S[i + 2] and S[i] != S[i + 1] and S[i + 1] != S[i + 2]:
				continue
			return False
		return True
	for i in range(L):
		if used[i]:
			continue
		used[i] = True
		tmp = S[n]
		S[n] = D[i]
		if(dfs(n + 1)):
			return True
		used[i] = False
		S[n] = tmp
	return False
if dfs(0):
	print('YES')
else:
	print('NO')