#include<stdio.h>
int mod = 1000000007;
int dp[2][1000001];
main(){
    int N;
    scanf("%d",&N);
    dp[0][0] = 0;
    dp[0][1] = 1;
    dp[1][0] = 1;
    dp[1][1] = 1;
    for(int i = 2;i <= N;i++){
        dp[0][i] = (dp[1][i-1]+dp[1][i-2]) % mod;
        dp[1][i] = dp[0][i-1];
    }
    printf("%d\n",dp[0][N]);
}