#include<iostream> #include<iomanip> #include<cmath> #include<string> #include<cstring> #include<vector> #include<list> #include<algorithm> #include<map> #include<set> #include<queue> #include<stack> using namespace std; typedef long long ll; #define fi first #define se second #define mp make_pair #define mt make_tuple #define pqueue priority_queue const int inf=1e9+7; const ll mod=1e9+7; const ll mod1=998244353; const ll big=1e18; const double PI=2*asin(1); int main() { int N; cin>>N; int ans = 0; for(int i=0;i<=N;++i) { for(int j=0;j<=i;++j) { if(N>=5*i+2*j && (N-5*i-2*j)%3==0) ans++; } } cout<<ans<<endl; }