q198446077

a, p1, b, p2, c, p3, d = raw_input().split()
if (a>=0 and a<=255 and b>=0 and b<=255 and c>=0 and c<=255 and d>=0 and d<=255 and
    p1 == '.' and p2 == '.' and p3 == '.'):
  print('YES')
else:
  print('NO')