#region Header #!/usr/bin/env python3 # from typing import * import sys import io import math import collections import decimal import itertools from queue import PriorityQueue import bisect import heapq def input(): return sys.stdin.readline()[:-1] sys.setrecursionlimit(1000000) #endregion # _INPUT = """# paste here... # """ # sys.stdin = io.StringIO(_INPUT) MOD = 1000000007 def main(): N = int(input()) dp = [[0, 0, 0] for _ in range(max(N, 3))] dp[0][0] = 0 dp[0][1] = 1 dp[0][2] = 0 dp[1][0] = 1 dp[1][1] = 0 dp[1][2] = 1 dp[2][0] = 1 dp[2][1] = 1 dp[2][2] = 0 for i in range(3, N): dp[i][0] = dp[i-1][1] + dp[i-1][2] dp[i][1] = dp[i-1][0] dp[i][2] = dp[i-1][1] print(sum(dp[N-1]) % MOD) if __name__ == '__main__': main()