arr = []
arr.push gets.chomp
arr.push gets.chomp
x = arr[0].split('.')
y = arr[1].split('.')
if x[0] == y[0]
  puts arr.sort.reverse == arr ? 'YES' : 'NO'
else
  puts x[0].to_i > y[0].to_i ? 'YES' : 'NO'
end