local ffi = require 'ffi'
local C, ct = ffi.C, ffi.typeof 'int64_t[1]'
ffi.cdef [[
int printf(const char *, ...);
int scanf(const char *, ...);
]]

C.printf("%ld\n", (function (n)
	C.scanf("%ld",n)
	local a,b,c=n[0],n[0],n[0]*2
	while a~=0 do local t=a/2 a,b,c=t,b+t,(2*t+a>c and 2*t+a or c) end
	return c-b>=0 and c-b or b-c
end)(ct()))