import strutils, math

proc fn(i: int): int =
  i mod (10 ^ 9 + 7)

let
  N = stdin.readLine.parseInt
  n = N mod 2
var
  k1, k2, p: array[2, int]


k1[1] = 1
for i in 2 .. N:
  let j = i mod 2

  k1[j] = p[j xor 1]
  k2[j] = k1[j xor 1]
  p[j] = (k1[j xor 1] + k2[j xor 1]).fn


echo (k1[n] + k2[n] + p[n]).fn