#include <stdio.h>
#define m 1000000007
int n, dp[100010][2];

int main()
{
    freopen(".15.in","r",stdin);
    freopen(".15.out","w",stdout);
    scanf("%d", &n);
    dp[0][0] = dp[0][1] = 1;
    for(int i = 1 ; i < n ; i++ )
        for(int j = 0 ; j < 2 ; j++ )
            if( j == 1 ) dp[i][j] = (dp[i-1][1]+dp[i-1][0])%m;
            else dp[i][j] = dp[i-1][1]%m;
    printf("%d\n", (dp[n-1][0]+dp[n-1][1])%m );
    return 0;
}