#include<iostream>
using namespace std;
const int N = 1e9 + 7;
int main() {
int n;
cin >> n;
if (n <= 2) {
cout << 1 %N << endl;
return 0;
}
long long a = 1, b = 1;
for (int i = 3; i <= n; i++) {
long long c = (a + b) %N;
a = b;
b = c;
}
cout << b % N << endl;
return 0;
}