#include // c #include // io #include #include #include #include // container #include #include #include #include #include #include // other #include #include #include #include #include using namespace std; using i32=int32_t;using i64=int64_t;using ll =i64;using uint=uint32_t;using ull=uint64_t; template using matrix=vector >; #define ALL(c) (begin(c)),(end(c)) #define REP(i,n) FOR(i,0,n) #define REPr(i,n) FORr(i,0,n) #define FOR(i,l,r) for(int i=(int)(l);i<(int)(r);++i) #define FORr(i,l,r) for(int i=(int)(r)-1;i>=(int)(l);--i) #define EACH(it,o) for(auto it = (o).begin(); it != (o).end(); ++it) #define IN(l,v,r) ((l)<=(v) && (v)<(r)) #define UNIQUE(v) v.erase(unique(ALL(v)),v.end()) //debug #define DUMP(x) cerr << #x << " = " << (x) #define LINE() cerr<< " (L" << __LINE__ << ")" class range { private: struct Iter{ int v; int operator*(){return v;} bool operator!=(Iter& itr) {return v < itr.v;} void operator++() {++v;} }; Iter i, n; public: range(int n) : i({0}), n({n}) {} range(int i, int n) : i({i}), n({n}) {} Iter& begin() {return i;} Iter& end() {return n;} }; //output template ostream& operator << (ostream& os, const vector& as){REP(i,as.size()){if(i!=0)os<<" "; os< ostream& operator << (ostream& os, const vector>& as){REP(i,as.size()){if(i!=0)os< ostream& operator << (ostream& os, const set& ss){for(auto a:ss){if(a!=ss.begin())os<<" "; os< ostream& operator << (ostream& os, const pair& p){os< ostream& operator << (ostream& os, const map& m){bool isF=true;for(auto& p:m){if(!isF)os< ostream& operator << (ostream& os, const tuple& t){os << get<0>(t);return os;} template ostream& operator << (ostream& os, const tuple& t){os << get<0>(t)<<" "<(t);return os;} template ostream& operator << (ostream& os, const tuple& t){os << get<0>(t)<<" "<(t)<<" "<(t);return os;} template ostream& operator << (ostream& os, const tuple& t){os << get<0>(t)<<" "<(t)<<" "<(t)<<" "<(t);return os;} template ostream& operator << (ostream& os, const tuple& t){os << get<0>(t)<<" "<(t)<<" "<(t)<<" "<(t)<<" "<(t);return os;} template ostream& operator << (ostream& os, const tuple& t){os << get<0>(t)<<" "<(t)<<" "<(t)<<" "<(t)<<" "<(t)<<" "<(t);return os;} template ostream& operator << (ostream& os, const tuple& t){os << get<0>(t)<<" "<(t)<<" "<(t)<<" "<(t)<<" "<(t)<<" "<(t)<<" "<(t);return os;} //input char tmp[1000]; #define nextInt(n) scanf("%d",&n) #define nextLong(n) scanf("%lld",&n) //I64d #define nextDouble(n) scanf("%lf",&n) #define nextChar(n) scanf("%c",&n) #define nextString(n) scanf("%s",tmp);n=tmp // values template T INF(){assert(false);}; template<> int INF(){return 1<<28;}; template<> ll INF(){return 1LL<<58;}; template<> double INF(){return 1e16;}; template T EPS(){assert(false);}; template<> int EPS(){return 1;}; template<> ll EPS(){return 1LL;}; template<> double EPS(){return 1e-8;}; template<> long double EPS(){return 1e-8;}; template T pmod(T v,U M){return (v%M+M)%M;} ll gcd_positive(ll a,ll b) { return b == 0 ? a : gcd_positive(b,a%b); } ll gcd(ll a,ll b) { return gcd_positive(abs(a), abs(b)); } ll lcm(ll a,ll b){return a/gcd(a,b)*b;} class Main{ public: vector dp; void run(){ int K;cin >> K; double l=0,r=1e10; REP(t,200){ double m=(l+r)/2; //check vector dp(201); for(int n=1;n<=K;n++){ for(int j=1;j<=6;j++){ if(n-j>=0)dp[n]+=dp[n-j]; else dp[n]+=m; } dp[n]=dp[n]/6+1; } if(dp[K]>=m)l=m; else r=m; } cout << r <