/* 
 *     Author:  srtry
 *     Created: 2025-05-10T18:42:06+09:00
 *     Coding:  utf-8-unix
 */

use proconio::input;
use std::io::{stdout,Write,BufWriter};

const BIG:usize = 1000000007;

fn main() {
    input!{
        n:usize
    }

    let out = stdout();
    let mut out = BufWriter::new(out.lock());
    // 0:K 1:P
    let mut dp:Vec<Vec<usize>> = vec![vec![0,0];n+1];
    dp[1] = vec![1,0];
    dp[2] = vec![1,1];
    dp[3] = vec![1,1];

    for i in 4..=n {
        dp[i][0] = (dp[i-1][1] + dp[i-2][1])%BIG;
        dp[i][1] = (dp[i-2][1] + dp[i-3][1])%BIG;
    }
    write!(out, "{}", (dp[n][0]+dp[n][1])%BIG).unwrap();
}