local ffi = require("ffi")
local C = ffi.C
ffi.cdef[[
long long atoll(const char*);
]]

local function lltonumber(str)
  return C.atoll(str)
end
local n = lltonumber(io.read())
local ret = 0LL
local mul = 1LL
while 0LL < n do
  if n % 2LL == 1LL then
    ret = mul
  end
  mul = mul * 2LL
  n = n / 2LL
end
ret = tostring(ret):gsub("LL", "")
print(ret)