#include <vector> #include <list> #include <map> #include <set> #include <queue> #include <deque> #include <stack> #include <bitset> #include <algorithm> #include <functional> #include <numeric> #include <utility> #include <sstream> #include <iostream> #include <iomanip> #include <cstdio> #include <cmath> #include <cstdlib> #include <cctype> #include <string> #include <cstring> #include <ctime> #include <fstream> using namespace std; inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v; } template<class T> inline string toString(T x) { ostringstream sout; sout << x; return sout.str(); } template<class T> inline T sqr(T x) { return x*x; } typedef vector<int> vi; typedef vector<vi> vvi; typedef vector<long long int> vll; typedef vector<string> vs; typedef pair<int, int> pii; typedef long long ll; //repetition //------------------------------------------ #define FOR(i,a,b) for(int i=(a);i<(b);++i) #define rep(i,n) FOR(i,0,n) #define P(p) cout<<(p)<<endl; #define VEC_2D(a,b) vector<vector<int> >(a, vector<int>(b, 0)) #define ALL(a) (a).begin(),(a).end() #define RALL(a) (a).rbegin(), (a).rend() #define pb push_back #define mp make_pair #define INF (1100000000) #define SZ(a) int((a).size()) #define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i) #define EXIST(s,e) ((s).find(e)!=(s).end()) #define SORT(c) sort((c).begin(),(c).end()) #define MOD 1000000007LL #define FSP(a) cout << fixed << setprecision(a) int gcd(int x, int y) { if (y == 0) return x; else return gcd(y, x%y); } ll lcm(ll a, ll b) { return a / gcd(a, b) * b; } bool is_prime(int n) { for (int i = 2; i * i <= n; i++) { if (n % i == 0) return false; } return n != 1; } map<int, int> prime_factor(int n) { map<int, int> res; for (int i = 2; i * i <= n; i++) { while (n % i == 0) { ++res[i]; n /= i; } } if (n != 1) res[n] = 1; return res; } int extgcd(int a, int b, int& x, int& y) {// int d = a; if (b != 0) { d = extgcd(b, a%b, y, x); y -= (a / b)*x; } else { x = 1; y = 0; } return d; } ll mod_pow(ll x, ll n, ll mod) { if (n == 0) return 1; ll res = mod_pow(x * x % mod, n / 2, mod); if (n & 1) res = res * x % mod; return res; } vector<string> split(const string &str, char delim) { vector<string> res; size_t current = 0, found; while ((found = str.find_first_of(delim, current)) != string::npos) { res.push_back(string(str, current, found - current)); current = found + 1; } res.push_back(string(str, current, str.size() - current)); return res; } bool is_kadomatsu(int a, int b, int c) { if (a == b || a == c || b == c)return false; if (a > b && c > b) return true; if (a < b && c < b)return true; return false; } struct UF { int n; vi d; UF(){} UF(int n):n(n),d(n,-1){} int root(int v) { if (d[v] < 0) return v; return d[v] = root(d[v]); } bool unite(int x, int y) { x = root(x); y = root(y); if (x == y) return false; if (size(x) < size(y)) swap(x, y); d[x] += d[y]; d[y] = x; return true; } int size(int v) { return -d[root(v)]; } }; vector<int> divisor(int n) { if (n == 1) return{}; vi res; for (int i = 1; i*i <= n; i++) { if (n%i == 0) { res.emplace_back(i); if (i != 1 && i != n / i)res.emplace_back(n / i); } } return res; } //------------------------------------------------------------- int main() { cin.tie(0); ios::sync_with_stdio(false); string s = "1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991"; int n; cin >> n; vi d; int size = s.size(); rep(i, size) { d.push_back(s[i] - '0'); } int val = 0; for (int i = size - 1; i >= 0; i--) { d[i] = d[i] * n + val; val = d[i] / 10; d[i] %= 10; } cout << val << "."; rep(i, size)cout << d[i]; cout << endl; return 0; //ifstream ifs("soc-LiveJournal1.txt"); //グラフの読み込み //ofstream output("soc-LiveJournal2.txt"); //int u, v; //string s; //bool is_0_start = false; //int count = 0; //rep(i, 4) getline(ifs, s); //for (; ifs >> u >> v;) { // if (u == 0) is_0_start = true; // if (!is_0_start) { // u--; // v--; // } // count++; // if(count%10000==0)cout << count << endl; // output << u << " " << v << endl; //} }