#include<iostream>
#include<cstdio>
using namespace std;
unsigned long long k,f1=1,f2=1,f;
int main()
{
scanf("%d",&k);
if(k==0) cout<<"0"<<endl;
else if(k==1 || k==2) cout<<"1"<<endl;
else{
	for(int i=3;i<=k;i++){
		f=f1+f2;
		f1=f2;
		f2=f;
	}
	printf("%d",f%1000000007);
}
return 0;
}