#include using namespace std; #define int long long #define rep(i, n) for (int i = 0; i < (int)(n); i++) #define REP(i, n) for (int i = 1; i <= (int)(n); i++) #define rev(i, n) for(int i = (int)(n - 1); i >= 0; i--) #define REV(i, n) for(int i = (int)(n); i > 0; i--) #define pb push_back #define all(v) (v).begin(), (v).end() #define vi vector #define vvi vector> #define vc vector #define vvc vector> #define vs vector #define vvs vector > #define pq priority_queue using ll = long long; /* ----------------よく使う数字や配列----------------- */ int dx[] = { 1,0,-1,0 }; int dy[] = { 0,1,0,-1 }; const int INF = 2000000000; constexpr ll mod = 1e9 + 7; constexpr long double pi = 3.141592653589793238462643383279; /* ----------------------end----------------------- */ /*---------------------template----------------------*/ /*----------------------end--------------------------*/ /* --------------------ライブラリ--------------------*/ bool isprime(ll a)//素数判定、primeならtrue,違うならfalse { if (a < 2) return false; else if (a == 2) return true; else if (a % 2 == 0) return false; double m = sqrt(a); for (int i = 3; i <= m; i += 2) { if (a % i == 0) { return false; } } // 素数である return true; } ll ketasum(ll n) { //各桁の和 ll sum = 0; while (n != 0) { sum += n % 10; n /= 10; } return sum; } /* ----------------------end----------------------- */ /*---------------------臨時関数----------------------*/ /*----------------------end-------------------------*/ signed main(){ int cnt=0; int N;cin>>N; int A=N/5; for(int i=A;i>=0;i--){ for(int j=i;j>=0;j--){ if((N-(i*5+j*2))%3==0&&(N-(i*5+j*2))/3>=0){ cnt++; } } } cout<