first_string = input()
num_s = first_string.split(" ")

a_fir = int(num_s[0])
a_sec = int(num_s[1])
a_thi = int(num_s[2])
a_for = int(num_s[3])

if a_fir < a_sec and a_thi > a_for:
	print("YES")
else:
	print("NO")