#include #include #include using namespace std; #define MOD 1e9+7 #define int long long signed main(){ int N; cin>>N; int mod = MOD; vector dp(N+1); dp = {0,1,2,2}; for(int i=4;i<=N;i++){ dp[i] = (dp[i-2] + dp[i-3]) % mod; } cout<