local mfl, mce = math.floor, math.ceil
local a, b = io.read("*n", "*n")
local lim = 40
for i = 1, lim do
  local ta = a % 10
  a = mfl(a / 10)
  local tb = b % 10
  b = mfl(b / 10)
  if ta < tb then
    print("No") os.exit()
  end
end
print("Yes")