結果
| 問題 | No.75 回数の期待値の問題 |
| ユーザー |
 ysuzuki5321
|
| 提出日時 | 2020-03-23 21:59:25 |
| 言語 | C++14 (gcc 12.3.0 + boost 1.83.0) |
| 結果 |
AC
|
| 実行時間 | 36 ms / 5,000 ms |
| コード長 | 19,567 bytes |
| コンパイル時間 | 2,000 ms |
| コンパイル使用メモリ | 134,600 KB |
| 実行使用メモリ | 6,944 KB |
| 最終ジャッジ日時 | 2024-06-09 04:47:59 |
| 合計ジャッジ時間 | 3,116 ms |
|
ジャッジサーバーID （参考情報） |
judge2 / judge3 |
（要ログイン）
テストケース
テストケース表示| 入力 | 結果 | 実行時間 実行使用メモリ |
|---|---|---|
| testcase_00 | AC | 3 ms
6,812 KB |
| testcase_01 | AC | 3 ms
6,940 KB |
| testcase_02 | AC | 4 ms
6,940 KB |
| testcase_03 | AC | 4 ms
6,940 KB |
| testcase_04 | AC | 4 ms
6,940 KB |
| testcase_05 | AC | 3 ms
6,940 KB |
| testcase_06 | AC | 4 ms
6,940 KB |
| testcase_07 | AC | 4 ms
6,944 KB |
| testcase_08 | AC | 4 ms
6,940 KB |
| testcase_09 | AC | 4 ms
6,940 KB |
| testcase_10 | AC | 4 ms
6,944 KB |
| testcase_11 | AC | 5 ms
6,944 KB |
| testcase_12 | AC | 5 ms
6,940 KB |
| testcase_13 | AC | 5 ms
6,940 KB |
| testcase_14 | AC | 5 ms
6,940 KB |
| testcase_15 | AC | 6 ms
6,940 KB |
| testcase_16 | AC | 18 ms
6,940 KB |
| testcase_17 | AC | 29 ms
6,944 KB |
| testcase_18 | AC | 34 ms
6,940 KB |
| testcase_19 | AC | 36 ms
6,940 KB |
コンパイルメッセージ
main.cpp: In function 'int getArea(ll, ll)':
main.cpp:959:1: warning: control reaches end of non-void function [-Wreturn-type]
959 | }
| ^
ソースコード
#include <stdio.h>
#include <sstream>
#include <string.h>
#include <vector>
#include <map>
#include <algorithm>
#include <utility>
#include <set>
#include <cctype>
#include <queue>
#include <stack>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <deque>
#include <limits>
#include <iomanip>
#include <ctype.h>
#include <unordered_map>
#include <random>
#include <numeric>
#include <iostream>
#include <array>
#define _USE_MATH_DEFINES
#include <iostream>
#include <math.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ll, double> pld;
typedef pair<double, double> pdd;
typedef pair<double, ll> pdl;
typedef pair<int, char> pic;
typedef vector<ll> vl;
typedef vector<int> vi;
typedef priority_queue<ll, vector<ll>, greater<ll>> llgreaterq;
typedef priority_queue<pll, vector<pll>, greater<pll>> pllgreaterq;
typedef priority_queue<pair<ll, pll>, vector<pair<ll, pll>>, greater<pair<ll, pll>>> plpllgreaterq;
typedef priority_queue<vi, vector<vi>, greater<vi>> vigreaterq;
typedef priority_queue<vl, vector<vl>, greater<vl >> vlgreaterq;
int dx[] = { -1,0,1,0 };
int dy[] = { 0,-1,0,1 };
#define bit(x,v) ((ll)x << v)
#define rep(x,n) for(int x = 0;x < n;x++)
#define rep2(x,f,v) for(int x=f;x<v;x++)
// 許容する誤差ε
#define EPS (1e-10)
// 2つのスカラーが等しいかどうか
#define EQ(a,b) (std::abs(a-b) < EPS)
// 2つのベクトルが等しいかどうか
#define EQV(a,b) ( EQ((a).real(), (b).real()) && EQ((a).imag(), (b).imag()) )
#define all(a) a.begin(),a.end()
#define all0(a) memset(a,0,sizeof(a))
#define alm1(a) memset(a,-1,sizeof(a))
const ll INF = 1000000007;
const int MAX = 2000010;
const int MOD = 1000000007;
long long fac[MAX], finv[MAX], inv[MAX];
void COMinit() {
fac[0] = fac[1] = 1;
finv[0] = finv[1] = 1;
inv[1] = 1;
for (int i = 2; i < MAX; i++) {
fac[i] = fac[i - 1] * i % MOD;
inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
finv[i] = finv[i - 1] * inv[i] % MOD;
}
}
// 二項係数計算
long long COM(int n, int k) {
if (n < k) return 0;
if (n < 0 || k < 0) return 0;
return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}
ll gcd(ll a, ll b) {
if (b == 0) return a;
return gcd(b, a % b);
}
int pr[100010];
int lank[100010];
void uini(int n) {
for (size_t i = 0; i <= n; i++)
{
pr[i] = i;
lank[i] = 1;
}
}
int parent(int x) {
if (x == pr[x]) return x;
return pr[x] = parent(pr[x]);
}
int same(int x, int y) {
return parent(x) == parent(y);
}
bool unit(int x, int y) {
int px = parent(x);
int py = parent(y);
if (px == py) return false;
if (lank[py] < lank[px]) {
pr[py] = px;
lank[px] += lank[py];
}
else {
pr[px] = py;
lank[py] += lank[px];
}
return true;
}
ll bit[200010];
int max_n = 200000;
int pm = 0;
void add(int x) {
while (max_n >= x)
{
bit[x]++;
x += x & -x;
}
}
void sub(int x) {
while (max_n >= x)
{
bit[x]--;
x += x & -x;
}
}
ll merge(ll* a, int left, int mid, int right) {
ll n1 = mid - left;
ll n2 = right - mid;
vector<int> L(n1 + 1);
vector<int> R(n2 + 1);
for (size_t i = 0; i < n1; i++)
{
L[i] = a[left + i];
}
for (size_t i = 0; i < n2; i++)
{
R[i] = a[mid + i];
}
L[n1] = INF;
R[n2] = INF;
ll i = 0;
ll j = 0;
ll r = 0;
for (size_t k = left; k < right; k++)
{
if (L[i] <= R[j]) {
a[k] = L[i];
i++;
}
else {
a[k] = R[j];
r += n1 - i;
j++;
}
}
return r;
}
ll merge2(pair<int, char>* a, int left, int mid, int right) {
ll n1 = mid - left;
ll n2 = right - mid;
vector<pair<int, char>> L(n1 + 1);
vector<pair<int, char>> R(n2 + 1);
for (size_t i = 0; i < n1; i++)
{
L[i] = a[left + i];
}
for (size_t i = 0; i < n2; i++)
{
R[i] = a[mid + i];
}
L[n1] = make_pair(INF, ' ');
R[n2] = make_pair(INF, ' ');
ll i = 0;
ll j = 0;
ll r = 0;
for (size_t k = left; k < right; k++)
{
if (L[i].first <= R[j].first) {
a[k] = L[i];
i++;
}
else {
a[k] = R[j];
r += n1 - i;
j++;
}
}
return r;
}
ll mergeSort2(pair<int, char>* a, int left, int right) {
ll res = 0;
if (left + 1 < right) {
int mid = (left + right) / 2;
res = mergeSort2(a, left, mid);
res += mergeSort2(a, mid, right);
res += merge2(a, left, mid, right);
}
return res;
}
ll mergeSort(ll* a, int left, int right) {
ll res = 0;
if (left + 1 < right) {
int mid = (left + right) / 2;
res = mergeSort(a, left, mid);
res += mergeSort(a, mid, right);
res += merge(a, left, mid, right);
}
return res;
}
int partition(pair<int, char>* a, int p, int r) {
pair<int, char> x = a[r];
int i = p - 1;
for (size_t j = p; j < r; j++)
{
if (a[j].first <= x.first) {
i++;
swap(a[i], a[j]);
}
}
swap(a[i + 1], a[r]);
return i + 1;
}
void quick(pair<int, char>* a, int p, int r) {
if (p < r) {
int q = partition(a, p, r);
quick(a, p, q - 1);
quick(a, q + 1, r);
}
}
ll n;
int ci = 0;
ll P[1000010];
struct Node {
int key;
int priority;
Node* parent, * left, * right;
Node(int key, int priority);
Node() {}
};
Node NIL;
Node::Node(int key, int priority) : key(key), priority(priority) {
left = &NIL;
right = &NIL;
}
Node* root = new Node();
void cenrec(Node* k) {
if (k->key == NIL.key) return;
cenrec(k->left);
cout << " " << k->key;
cenrec(k->right);
}
void fastrec(Node* k)
{
if (k->key == NIL.key) return;
cout << " " << k->key;
fastrec(k->left);
fastrec(k->right);
}
void insert(Node* v) {
Node* y = &NIL;
Node* x = root;
while (x->key != NIL.key)
{
y = x;
if (v->key < x->key) {
x = x->left;
}
else {
x = x->right;
}
}
v->parent = y;
if (y->key == NIL.key) {
root = v;
}
else if (v->key < y->key) {
y->left = v;
}
else {
y->right = v;
}
}
Node* find(Node* k, ll v)
{
if (k->key == NIL.key) return &NIL;
if (k->key == v) return k;
if (v < k->key) return find(k->left, v);
return find(k->right, v);
}
void delp12(Node* x) {
if (x->key == NIL.key) return;
Node* l = x->left;
Node* r = x->right;
Node* pr = x->parent;
if (l->key == NIL.key
&& r->key == NIL.key) {
if (pr->left == x) {
pr->left = &NIL;
}
else pr->right = &NIL;
}
else if (l->key != NIL.key) {
if (pr->left == x) {
pr->left = l;
}
else pr->right = l;
l->parent = pr;
}
else if (r->key != NIL.key) {
if (pr->left == x) {
pr->left = r;
}
else pr->right = r;
r->parent = pr;
}
}
Node* get_next(Node* k) {
if (k->key == NIL.key) return &NIL;
Node* res = get_next(k->left);
if (res->key != NIL.key) return res;
return k;
}
void del(Node* x) {
if (x->key == NIL.key) return;
Node* l = x->left;
Node* r = x->right;
Node* pr = x->parent;
if (l->key != NIL.key && r->key != NIL.key) {
Node* nex = get_next(r);
x->key = nex->key;
delp12(nex);
}
else {
delp12(x);
}
}
Node* rightRotate(Node* t) {
Node* s = t->left;
t->left = s->right;
s->right = t;
return s;
}
Node* leftRotate(Node* t) {
Node* s = t->right;
t->right = s->left;
s->left = t;
return s;
}
Node* _insert(Node* t, int key, int priority) {
if (t->key == NIL.key) {
return new Node(key, priority);
}
if (key == t->key) {
return t;
}
if (key < t->key) {
t->left = _insert(t->left, key, priority);
if (t->priority < t->left->priority) {
t = rightRotate(t);
}
}
else {
t->right = _insert(t->right, key, priority);
if (t->priority < t->right->priority) {
t = leftRotate(t);
}
}
return t;
}
Node* delete1(Node* t, int key);
Node* _delete(Node* t, int key) {
if (t->left->key == NIL.key && t->right->key == NIL.key) {
return &NIL;
}
else if (t->left->key == NIL.key) {
t = leftRotate(t);
}
else if (t->right->key == NIL.key) {
t = rightRotate(t);
}
else
{
if (t->left->priority > t->right->priority) {
t = rightRotate(t);
}
else
t = leftRotate(t);
}
return delete1(t, key);
}
Node* delete1(Node* t, int key) {
if (t->key == NIL.key) {
return &NIL;
}
if (key < t->key) {
t->left = delete1(t->left, key);
}
else if (key > t->key) {
t->right = delete1(t->right, key);
}
else return _delete(t, key);
return t;
}
int H;
int left(int i) {
return i * 2 + 1;
}
int right(int i) {
return i * 2 + 2;
}
struct edge {
int from, to;
ll val;
edge(int from, int to, ll val) : from(from), to(to), val(val) {}
};
ll k;
int _rank[1010];
int temp[1010];
bool compare_sa(int i, int j) {
if (_rank[i] != _rank[j]) return _rank[i] < _rank[j];
else {
int ri = i + k <= n ? _rank[i + k] : -1;
int rj = j + k <= n ? _rank[j + k] : -1;
return ri < rj;
}
}
void construct_sa(string S, int* sa) {
n = S.length();
for (size_t i = 0; i <= n; i++)
{
sa[i] = i;
_rank[i] = i < n ? S[i] : -1;
}
for (k = 1; k <= n; k *= 2)
{
sort(sa, sa + n + 1, compare_sa);
// saはソート後の接尾辞の並びになっている、rankは元の位置のindexを保持したまま、更新されている。
// ピンとこなかった部分
temp[sa[0]] = 0;
for (size_t i = 1; i <= n; i++)
{
temp[sa[i]] = temp[sa[i - 1]] + (compare_sa(sa[i - 1], sa[i]) ? 1 : 0);
}
for (size_t i = 0; i <= n; i++)
{
_rank[i] = temp[i];
}
}
}
bool contain(string S, int* sa, string T) {
int a = 0, b = S.length();
// sa は 接尾辞が辞書順に並んでいる、入っているのはその位置のインデックス
while (b - a > 1) {
int c = (a + b) / 2;
if (S.compare(sa[c], T.length(), T) < 0) a = c;
else b = c;
}
return S.compare(sa[b], T.length(), T) == 0;
}
#define bit(x,v) ((ll)x << v)
class BIT {
static const int MAX_N = 500010;
public:
BIT() { memset(bit, 0, sizeof(bit)); }
ll bit[MAX_N + 1], n;
ll sum(int i) {
ll s = 0;
while (i > 0)
{
s += bit[i];
i -= i & -i;
}
return s;
}
void add(int i, int x) {
while (i <= n)
{
bit[i] += x;
i += i & -i;
}
}
};
struct UnionFind {
vector<int> A;
UnionFind(int n) : A(n, -1) {}
int find(int x) {
if (A[x] < 0) return x;
return A[x] = find(A[x]);
}
void unite(int x, int y) {
x = find(x), y = find(y);
if (x == y) return;
if (A[x] > A[y]) swap(x, y);
A[x] += A[y];
A[y] = x;
}
int ngroups() {
int ans = 0;
for (auto a : A) if (a < 0) ans++;
return ans;
}
};
void yes() { cout << "Yes\n"; exit(0); }
void no() { cout << "No\n"; exit(0); }
vector<ll> getp(ll n) {
vector<ll> res;
ll a = 2;
if (n % 2 == 0) {
res.push_back(2);
while (n % 2 == 0)n /= 2;
}
for (ll i = 3; i * i <= n; i += 2)
{
if (n % i == 0) {
res.push_back(i);
while (n % i == 0)n /= i;
}
}
if (n != 1) res.push_back(n);
return res;
}
vector<ll> getp2(ll n) {
vector<ll> res;
ll a = 2;
if (n % 2 == 0) {
while (n % 2 == 0) { n /= 2; res.push_back(2); }
}
for (ll i = 3; i * i <= n; i += 2)
{
if (n % i == 0) {
while (n % i == 0) { n /= i; res.push_back(i); }
}
}
if (n != 1) res.push_back(n);
return res;
}
vector<pll> getp3(ll n) {
vector<pll> res;
ll a = 2;
int si = 0;
if (n % 2 == 0) {
res.push_back(make_pair(2, 0));
while (n % 2 == 0) { n /= 2; res[si].second++; }
si++;
}
for (ll i = 3; i * i <= n; i += 2)
{
if (n % i == 0) {
res.push_back(make_pair(i, 0));
while (n % i == 0) { n /= i; res[si].second++; }
si++;
}
}
if (n != 1) { res.push_back(make_pair(n,1)); }
return res;
}
vector<ll> getDivisors(ll n) {
vector<ll> res;
ll a = 2;
res.push_back(1);
for (ll i = 2; i * i <= n; i++)
{
if (n % i == 0) {
res.push_back(i);
if (n / i != i)
res.push_back(n / i);
}
}
return res;
}
struct ve {
public:
vector<ve> child;
int _t = INF;
ve(int t) :_t(t) {}
ve(ve _left, ve _right) {
_t = _left._t + _right._t;
child.push_back(_left);
child.push_back(_right);
}
bool operator<(const ve& t) const {
return _t > t._t;
}
};
vector<bool> elas(ll n) {
vector<bool> r(n);
fill(r.begin(), r.end(), 1);
r[0] = 0;
r[1] = 0;
for (ll i = 2; i * i < n; i++)
{
if (!r[i]) continue;
ll ti = i * 2;
while (ti < n)
{
r[ti] = false;
ti += i;
}
}
return r;
}
bool isPrime(ll v) {
for (ll i = 2; i * i <= v; i++)
{
if (v % i == 0) return false;
}
return true;
}
ll getpow(ll b,ll x, ll md) {
ll t = b;
ll res = 1;
while (x > 0)
{
if (x & 1) {
res *= t;
res %= md;
}
x >>= 1;
t *= t;
t %= md;
}
return res;
}
ll getpow(ll b, ll x) {
return getpow(b, x, INF);
}
class SegTree {
public :
const static int MAX_N = 100010;
const static int DAT_SIZE = (1 << 18) - 1;
int N, Q;
int A[MAX_N];
ll data[DAT_SIZE], datb[DAT_SIZE];
void init(int _n) {
N = 1;
while (N < _n) N <<= 1;
memset(data, 0, sizeof(data));
memset(datb, 0, sizeof(datb));
}
void init(int _n,ll iv) {
N = 1;
while (N < _n) N <<= 1;
rep(i, DAT_SIZE) {
data[i] = iv;
datb[i] = iv;
}
}
void add(int a, int b, int x) {
add(a, b + 1, x, 0, 0, N);
}
void add(int a, int b, int x, int k, int l, int r) {
if (a <= l && r <= b) {
data[k] += x;
}
else if (l < b && a < r) {
datb[k] += (min(b, r) - max(a, l)) * x;
add(a, b, x, k * 2 + 1, l, (l + r) / 2);
add(a, b, x, k * 2 + 2, (l + r)/2, r);
}
}
void change(int a, int b, int x) {
change(a, b + 1, x, 0, 0, N);
}
void change(int a, int b, int x, int k, int l, int r) {
if (a <= l && r <= b) {
data[k] = x;
}
else if (l < b && a < r) {
datb[k] = x;
change(a, b, x, k * 2 + 1, l, (l + r) / 2);
change(a, b, x, k * 2 + 2, (l + r) / 2, r);
}
}
ll sum(int a, int b) {
return sum(a, b + 1, 0, 0, N);
}
ll sum(int a, int b, int k, int l, int r) {
if (b <= l || r <= a) {
return 0;
}
if (a <= l && r <= b) {
return data[k] * (r - l) + datb[k];
}
ll res = (min(b, r) - max(a, l)) * data[k];
res += sum(a, b, k * 2 + 1, l, (l + r) / 2);
res += sum(a, b, k * 2 + 2, (l + r) / 2, r);
return res;
}
};
class Segment;
class Circle;
class Point {
public:
double x, y;
Point(double x = 0, double y = 0) :x(x), y(y) {}
Point operator + (Point p) { return Point(x + p.x, y + p.y); }
Point operator - (Point p) { return Point(x - p.x, y - p.y); }
Point operator * (double a) { return Point(a * x, a * y); }
Point operator / (double a) { return Point(x / a, y /a); }
double abs() { return sqrt(norm()); }
double norm() { return x * x + y * y; }
bool operator < (const Point& p)const {
return x != p.x ? x < p.x : y < p.y;
}
bool operator == (const Point& p) const {
return fabs(x - p.x) < EPS && fabs(y - p.y) < EPS;
}
static double dot(Point a, Point b) {
return a.x * b.x + a.y * b.y;
}
static double cross(Point a, Point b) {
return a.x * b.y - a.y * b.x;
}
static bool isOrthogonal(Point a, Point b) {
return EQ(dot(a, b), 0.0);
}
static bool isOrthogonal(Point a1, Point a2, Point b1, Point b2) {
return isOrthogonal(a1 - a2, b1 - b2);
}
static bool isOrthogonal(Segment s1, Segment s2);
static bool isPalallel(Point a, Point b) {
return EQ(cross(a, b), 0.0);
}
static bool isPalallel(Point a1, Point a2, Point b1, Point b2) {
return isPalallel(a1 - a2, b1 - b2);
}
static bool isPalallel(Segment s1, Segment s2);
static const int COUNTER_CLOCKWISE = 1;
static const int CLOCKWISE = -1;
static const int ONLINE_BACK = 2;
static const int ONLINE_FRONT = -2;
static const int ON_SEGMENT = 0;
static int ccw(Point p0, Point p1, Point p2) {
Point a = p1 - p0;
Point b = p2 - p0;
if (cross(a, b) > EPS) return COUNTER_CLOCKWISE;
if (cross(a, b) < -EPS) return CLOCKWISE;
if (dot(a, b) < -EPS) return ONLINE_BACK;
if (a.norm() < b.norm()) return ONLINE_FRONT;
return ON_SEGMENT;
}
static bool intersect(Point p1, Point p2, Point p3, Point p4) {
return (ccw(p1, p2, p3) * ccw(p1, p2, p4) <= 0
&& ccw(p3, p4, p1) * ccw(p3, p4, p2) <= 0);
}
static bool intersect(Segment s1, Segment s2);
static Point project(Segment s, Point p);
static Point reflect(Segment s, Point p);
static Point getDistance(Point a, Point b) {
return (a - b).abs();
}
static double getDistanceLP(Segment s, Point p);
static double getDistanceSP(Segment s, Point p);
static double getDistance(Segment s1, Segment s2);
static Point getIntersection(Segment s1, Segment s2);
static pair<Point, Point> crossPoints(Circle c, Segment s);
};
class Segment {
public:
Point p1, p2;
Segment() {}
Segment(Point p1, Point p2) :p1(p1), p2(p2) {}
Point p1tp2() {
return p2 - p1;
}
Point p2tp1() {
return p1 - p2;
}
double abs() {
return std::abs(norm());
}
double norm() {
return (p2 - p1).norm();
}
};
bool Point::isOrthogonal(Segment s1, Segment s2) {
return EQ(dot(s1.p2 - s1.p1, s2.p2 - s2.p1), 0.0);
}
bool Point::isPalallel(Segment s1, Segment s2) {
return EQ(cross(s1.p2 - s1.p1, s2.p2 - s2.p1), 0.0);
}
bool Point::intersect(Segment s1, Segment s2) {
return intersect(s1.p1,s1.p2,s2.p1,s2.p2);
}
Point Point::project(Segment s, Point p) {
Point base = s.p2 - s.p1;
double r = Point::dot(p - s.p1, base) / base.norm();
return s.p1 + base * r;
}
Point Point::reflect(Segment s, Point p) {
return (project(s, p) * 2) - p;
}
double Point::getDistanceLP(Segment s, Point p) {
return std::abs(cross(s.p2 - s.p1,p-s.p1) / (s.p2 - s.p1).abs());
}
double Point::getDistanceSP(Segment s, Point p) {
if (dot(s.p2 - s.p1, p - s.p1) < 0.0) return (p - s.p1).abs();
if (dot(s.p1 - s.p2, p - s.p2) < 0.0) return (p - s.p2).abs();
return getDistanceLP(s,p);
}
double Point::getDistance(Segment s1, Segment s2) {
if (intersect(s1, s2)) return 0.0;
return min({ getDistanceSP(s1,s2.p1),getDistanceSP(s1,s2.p2)
,getDistanceSP(s2,s1.p1),getDistanceSP(s2,s1.p2) });
}
Point Point::getIntersection(Segment s1, Segment s2) {
// (s1.p1 - s2.p1).norm()
auto bs = s1.p2 - s1.p1;
auto n1 = s2.p1 - s1.p1;
auto n2 = s2.p2 - s1.p1;
auto c1 = std::abs(cross(n1, bs)) / bs.norm();
auto c2 = std::abs(cross(n2, bs)) / bs.norm();
return s2.p1 + (s2.p2 - s2.p1) * (c1 / (c1 + c2));
// c1:c2=t:1-t
// c2t=(1-t)c1
// t/(1-t)=c1/(c1+c2)
//
}
double arg(Point p) { return atan2(p.y, p.x); }
Point polar(double a, double r) { return Point(cos(r) * a, sin(r) * a); }
class Circle {
public:
Point c;
double r;
Circle(Point c=Point(),double r = 0.0) : c(c),r(r){}
static pair<Point, Point> getCrossPoints(Circle c1, Circle c2) {
double d = (c1.c - c2.c).abs(); // 中心点どうしの距離
double a = acos((c1.r * c1.r + d * d - c2.r * c2.r) / (2 * c1.r * d));
double t = arg(c2.c - c1.c);
return make_pair(c1.c + polar(c1.r, t + a), c1.c + polar(c1.r, t - a));
}
};
pair<Point, Point> Point::crossPoints(Circle c, Segment s) {
auto pp = project(s, c.c);
auto f = (pp - c.c).norm();
auto mu = sqrt(c.r * c.r - f );
auto e = s.p1tp2() / s.p1tp2().abs();
return make_pair(pp + e * mu, pp - e * mu);
}
ll divRm(string s, ll x) {
ll r = 0;
for (size_t i = 0; i < s.size(); i++)
{
r *= 10;
r += s[i] - '0';
r %= x;
}
return r;
}
ll cmbi(ll x, ll b) {
ll res = 1;
for (size_t i = 0; i < b; i++)
{
res *= x - i;
res %= INF;
res *= inv[b - i];
res %= INF;
}
return res;
}
double digsum(ll x) {
ll res = 0;
while (x > 0)
{
res += x % 10;
x /= 10;
}
return res;
}
bool maching(char a, char b) {
return (a == b || a == '?' || b == '?');
}
int getArea(ll x, ll v) {
for (size_t i = 1; i <= 3; i++)
{
if (x < v * i) return i - 1;
}
}
void solv() {
cin >> n;
double hi = 200;
double lo = 0;
rep (i,10000)
{
double mid = (hi + lo) / 2.0;
double dp[210];
all0(dp);
rep2(j,1, n + 1) {
dp[j] = 1;
for (int t = 1; t <= 6; t++)
{
if (j - t < 0)dp[j] += mid / 6.0;
else dp[j] += dp[j - t] / 6.0;
}
}
if (dp[n] > mid) {
lo = mid;
}
else {
hi = mid;
}
}
cout << fixed << setprecision(10) << lo << endl;
}
int main() {
//COMinit();
solv();
return 0;
}