#include #include #include #include #include #include #include #include using namespace std; #define REP(i,a,b) for(int i=a;i<(int)b;i++) #define rep(i,n) REP(i,0,n) typedef long long ll; int main() { unordered_map mp; int P[] = {2,3,5,7,11,13}; int C[] = {4,6,8,9,10,12}; rep(i, 6) rep(j, 6) { mp[P[i]*C[j]]++; } int K; cin >> K; cout << mp[K] / 36.0 << endl; return 0; }