using System; using System.Collections.Generic; using System.Linq; using System.IO; using System.Text; using System.Numerics; using System.Threading; using System.Runtime.CompilerServices; using System.Diagnostics; using static System.Math; using static System.Array; using static AtCoder.Cout; using static AtCoder.Tool; using static AtCoder.Graph; using ModInt = AtCoder_MOD.ModInt;using static AtCoder_MOD.ModCalc; //using ModInt = AtCoder_MOD.ModInt;using static AtCoder_MOD.ModCalc; namespace AtCoder { class AC { static readonly int MOD = ModInt.GetMod(); const int INF = int.MaxValue / 2; const long SINF = long.MaxValue / 3; static readonly int[] dI = { 0, 1, 0, -1, 1, -1, -1, 1 }; static readonly int[] dJ = { 1, 0, -1, 0, 1, 1, -1, -1 }; static void Main(string[] args) { //var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false }; Console.SetOut(sw); /*var th = new Thread(Run, 1 << 26); th.Start(); th.Join();*/ Run(); Console.Out.Flush(); } static void Run() { int Testcase = 1; //Testcase = Cin.Int; for (var _ = 0; _ < Testcase; _++) Solve(); } static void Solve() { int N = Cin.Int; var L = Cin.ReadSplit_Double; var K = Cin.Long; double l = 0, r = L.Max(); while (r - l > 1e-9) { var mid = (l + r) / 2; long cnt = 0; for(var i = 0; i < N; i++) { cnt += (long)(L[i] / mid); } if (cnt >= K) l = mid; else r = mid; } OutL(l); } } static class Permutation { private static void Search(List perms, Stack stack, T[] a) { int N = a.Length; if (N == 0) { perms.Add(stack.Reverse().ToArray()); } else { var b = new T[N - 1]; Array.Copy(a, 1, b, 0, N - 1); for (int i = 0; i < a.Length; ++i) { stack.Push(a[i]); Search(perms, stack, b); if (i < b.Length) { b[i] = a[i]; } stack.Pop(); } } } public static IEnumerable All(IEnumerable src) { var perms = new List(); Search(perms, new Stack(), src.ToArray()); return perms; } } public struct Edge { public int from, to; public long w; public double dw; public Edge(int to, long weight) { this.to = to; w = weight; from = -1; dw = -1; } public Edge(int from, int to, long weight) { this.from = from; this.to = to; w = weight; dw = -1; } public Edge(int to, double weight) { this.to = to; from = -1; w = -1; dw = weight; } } public static class Graph { const long inf = long.MaxValue / 3; public static List> Gen_Graph(int size) { var ret = new List>(); for (var i = 0; i < size; i++) ret.Add(new List()); return ret; } public static long[] Dijkstra(List> G, int st) { int N = G.Count(); long[] ret = new long[N]; var V = new Priority_Queue>((x, y) => Sig(x.Item1 - y.Item1)); for (var i = 0; i < N; i++) ret[i] = inf; ret[st] = 0; V.Enqueue(new Tuple(0, st)); while (V.Any()) { var cur = V.Dequeue(); int v = cur.Item2; long cd = cur.Item1; if (ret[v] < cd) continue; foreach (var ed in G[v]) { if (ret[ed.to] > cd + ed.w) { ret[ed.to] = cd + ed.w; V.Enqueue(new Tuple(ret[ed.to], ed.to)); } } } return ret; } public static long[] Bellman_Frod(List E, int st, int N, out bool neg_close) { var ret = new long[N]; for (var i = 0; i < N; i++) ret[i] = inf; ret[st] = 0; for (var i = 0; i < N; i++) { foreach (var ed in E) { if (ret[ed.from] != inf && ret[ed.to] > ret[ed.from] + ed.w) { if (i == N - 1) { neg_close = true; return ret; } ret[ed.to] = ret[ed.from] + ed.w; } } } neg_close = false; return ret; } } public class SCC { int n; struct Edge_S { public int from, to; public Edge_S(int f, int t) { from = f; to = t; } } List E; int[] id; public SCC(int size) { n = size; E = new List(); } public void Add_Edge(int from, int to) { E.Add(new Edge_S(from, to)); } public int[][] Scc_Result() { var start = new int[n + 1]; var nxt = new int[E.Count]; //var scc = new List>(); foreach (var ed in E) start[ed.from + 1]++; for (var i = 0; i < n; i++) start[i + 1] += start[i]; var itr = new int[n + 1]; for (var i = 0; i <= n; i++) itr[i] = start[i]; foreach (var ed in E) nxt[itr[ed.from]++] = ed.to; int now = 0; int[] ord = new int[n]; int[] low = new int[n]; id = new int[n]; var V = new Stack(); for (var i = 0; i < n; i++) ord[i] = -1; int nowid = 0; Action DFS = null; DFS = (v) => { low[v] = ord[v] = now++; V.Push(v); for (var i = start[v]; i < start[v + 1]; i++) { var nx = nxt[i]; if (ord[nx] == -1) { DFS(nx); low[v] = Min(low[v], low[nx]); } else { low[v] = Min(low[v], ord[nx]); } } if (low[v] == ord[v]) { while (true) { var u = V.Pop(); id[u] = nowid; ord[u] = n + 1; if (u == v) break; } nowid++; } }; for (var i = 0; i < n; i++) if (ord[i] == -1) DFS(i); for (var i = 0; i < n; i++) { id[i] = nowid - 1 - id[i]; itr[i] = 0; } var scc = new int[nowid][]; for (var i = 0; i < n; i++) itr[id[i]]++; for (var i = 0; i < nowid; i++) scc[i] = new int[itr[i]]; for (var i = 0; i < n; i++) scc[id[i]][--itr[id[i]]] = i; /* for (var i = 0; i < nowid; i++) scc.Add(new List()); for (var i = 0; i < n; i++) scc[id[i]].Add(i);*/ return scc; } public int v_id(int v) => id[v]; } public class Two_SAT { // use with SCC Library int n; bool[] result; SCC scc; readonly int md; public Two_SAT(int size) { n = size; result = new bool[n]; scc = new SCC(n << 1); md = n << 1; } public void Add_Closure(int i, bool fi, int j, bool fj) { if (!fi) i += n; if (!fj) j += n; scc.Add_Edge((i + n) % md, j); scc.Add_Edge((j + n) % md, i); } public bool Satisfy() { scc.Scc_Result(); for (var i = 0; i < n; i++) { int j = scc.v_id(i), k = scc.v_id(i + n); if (j == k) return false; result[i] = j > k; } return true; } public bool[] ans() => result; } public class Dinic { readonly int n; const int inf = int.MaxValue / 2; public class Edge_F { public int _to { get; set; } public long _cap { get; set; } public int _rev { get; set; } public Edge_F(int to, long cap, int rev) { _to = to; _cap = cap; _rev = rev; } } List> G; int[] level, itr; public Dinic(int vertice) { n = vertice; level = new int[n]; itr = new int[n]; G = new List>(); for (var _ = 0; _ < n; _++) G.Add(new List()); } /*================ ^ _ ^ ==================*/ //辺の追加(from->to,容量cap) public void Add_Edge(int from, int to, long cap) { G[from].Add(new Edge_F(to, cap, G[to].Count())); G[to].Add(new Edge_F(from, 0, G[from].Count() - 1)); } //bfsパート(levelの設定) void Bfs(int s) { //Fillはバージョン古いと使えないため... for (var i = 0; i < n; i++) level[i] = -1; level[s] = 0; var Q = new Queue(); Q.Enqueue(s); while (Q.Any()) { int v = Q.Dequeue(); foreach (var ed in G[v]) { if (ed._cap > 0 && level[ed._to] == -1) { level[ed._to] = level[v] + 1; Q.Enqueue(ed._to); } } } } //dfsパート(増加パスの探索) long Dfs(int v, int t, long f) { if (v == t) return f; for (var i = itr[v]; i < G[v].Count(); i++) { itr[v] = i; var ed = G[v][i]; if (ed._cap > 0 && level[v] < level[ed._to]) { var d = Dfs(ed._to, t, Min(f, ed._cap)); if (d > 0) { ed._cap -= d; G[ed._to][ed._rev]._cap += d; return d; } } } return 0; } //s->tの最大流を返す //一般:O(N^2M) //二部グラフマッチング:O(M*Sqrt(N)) //辺の容量が全て同じ:O(min(n^{2/3},m^{1/2})*m) //になるらしい public long Max_Flow(int s, int t) { long ret = 0; for (; ; ) { Bfs(s); if (level[t] == -1) return ret; for (var i = 0; i < n; i++) itr[i] = 0; var flow = 0L; do { ret += flow; flow = Dfs(s, t, inf); } while (flow > 0); } } //グラフの状況を返す public List> GetGraph() => G; } public class MinCostFlow { const long inf = long.MaxValue / 3; int n; public class Edge { public int _to, _cap, _rev; public long _cost; public bool _isrev; public Edge(int to, int cap, long cost, int rev, bool isrev) { _to = to; _cap = cap; _rev = rev; _cost = cost; _isrev = isrev; } } List> G; public MinCostFlow(int size) { n = size; G = new List>(); for (var i = 0; i < n; i++) G.Add(new List()); } /*辺の追加*/ public void Add_Edge(int s, int t, int cap, long cost) { G[s].Add(new Edge(t, cap, cost, G[t].Count(), false)); G[t].Add(new Edge(s, 0, -cost, G[s].Count() - 1, true)); } public long MinCost(int s, int t, int f) { long ret = 0; var h = new long[n]; var dist = new long[n]; var pre_v = new int[n]; var pre_e = new int[n]; var V = new Priority_Queue<(long, int)>((x, y) => Sig(x.Item1 - y.Item1)); while (f > 0) { for (var i = 0; i < n; i++) { dist[i] = inf; pre_v[i] = pre_e[i] = -1; } dist[s] = 0; V.Enqueue((0, s)); while (V.Any()) { var (cd, v) = V.Dequeue(); if (dist[v] < cd) continue; for (var i = 0; i < G[v].Count(); i++) { var ed = G[v][i]; if (ed._cap <= 0) continue; if (dist[ed._to] + h[ed._to] > cd + h[v] + ed._cost) { dist[ed._to] = cd + ed._cost + h[v] - h[ed._to]; pre_v[ed._to] = v; pre_e[ed._to] = i; V.Enqueue((dist[ed._to], ed._to)); } } } if (dist[t] == inf) { return -inf; } for (var i = 0; i < n; i++) h[i] += dist[i]; var nowflow = f; for (var now = t; now != s; now = pre_v[now]) { nowflow = Min(nowflow, G[pre_v[now]][pre_e[now]]._cap); } f -= nowflow; ret += nowflow * h[t]; for (var now = t; now != s; now = pre_v[now]) { var rv = G[pre_v[now]][pre_e[now]]._rev; G[pre_v[now]][pre_e[now]]._cap -= nowflow; G[now][rv]._cap += nowflow; } } return ret; } public List> GetEdges() => G; } public class LCA { List> G1; List> G2; int n; bool isweighted; int[] dist; long[] dist_w; int[,] par; public LCA(List> G) { G1 = G; G2 = null; n = G1.Count(); isweighted = false; dist = new int[n]; dist_w = null; par = new int[25, n]; } public LCA(List> G) { G1 = null; G2 = G; n = G2.Count(); isweighted = true; dist = new int[n]; dist_w = new long[n]; par = new int[25, n]; } public void Lca_Build(int root) { for (var i = 0; i < n; i++) { dist[i] = -1; if (isweighted) dist_w[i] = -1; } var dfs = new Stack(); dfs.Push(root); dist[root] = 0; if (isweighted) dist_w[root] = 0; par[0, root] = -1; while (dfs.Any()) { int v = dfs.Pop(); if (isweighted) { foreach (var ed in G2[v]) { if (dist[ed.to] != -1) continue; par[0, ed.to] = v; dist_w[ed.to] = dist[v] + ed.w; dist[ed.to] = dist[v] + 1; dfs.Push(ed.to); } } else { foreach (var nx in G1[v]) { if (dist[nx] != -1) continue; par[0, nx] = v; dist[nx] = dist[v] + 1; dfs.Push(nx); } } } for (var i = 1; i < 25; i++) { for (var j = 0; j < n; j++) { if (par[i - 1, j] == -1) par[i, j] = -1; else par[i, j] = par[i - 1, par[i - 1, j]]; } } } public int Lca(int u, int v) { if (dist[u] < dist[v]) { var kep = u; u = v; v = kep; } for (var i = 0; i < 30; i++) { if ((((dist[u] - dist[v]) >> i) & 1) != 0) { u = par[i, u]; } } if (u == v) return u; for (var i = 24; i >= 0; i--) { if (par[i, u] != par[i, v]) { u = par[i, u]; v = par[i, v]; } } return par[0, u]; } public int[] GetDist() => dist; public long[] GetWeightedDist() => dist_w; } public class Priority_Queue { private List Q; private readonly Comparison Func_Compare; public Priority_Queue(Comparison comp) { Func_Compare = comp; Q = new List(); } private void PushHeap(T item) { int n = Q.Count(); Q.Add(item); while (n != 0) { int pIndex = (n - 1) / 2; if (Func_Compare(Q[n], Q[pIndex]) < 0) { Swap(n, pIndex); } else { break; } n = pIndex; } } private void PopHeap() { int n = Q.Count() - 1; Q[0] = Q[n]; Q.RemoveAt(n); int cur = 0; int comp; while (2 * cur + 1 <= n - 1) { int c1 = 2 * cur + 1; int c2 = 2 * (cur + 1); if (c1 == n - 1) { comp = c1; } else { comp = Func_Compare(Q[c1], Q[c2]) < 0 ? c1 : c2; } if (Func_Compare(Q[cur], Q[comp]) > 0) { Swap(cur, comp); } else { break; } cur = comp; } } [MethodImpl(MethodImplOptions.AggressiveInlining)] private void Swap(int a, int b) { T keep = Q[a]; Q[a] = Q[b]; Q[b] = keep; } [MethodImpl(MethodImplOptions.AggressiveInlining)] public void Enqueue(T value) => PushHeap(value); [MethodImpl(MethodImplOptions.AggressiveInlining)] public T Dequeue() { T ret = Q[0]; PopHeap(); return ret; } public T Peek() => Q[0]; public int Count() => Q.Count(); public bool Any() => Q.Any(); } public class SegmentTree { //1-indexed type int n; T[] Tree; Func f; T ex; int len; [MethodImpl(MethodImplOptions.AggressiveInlining)] public SegmentTree(int size, Func fun, T exvalue) { ex = exvalue; f = fun; len = size; n = 1; while (n < size) n <<= 1; Tree = new T[n << 1]; for (var i = 0; i < Tree.Length; i++) Tree[i] = ex; } [MethodImpl(MethodImplOptions.AggressiveInlining)] public void Set_All() { for (var i = n - 1; i >= 1; i--) Tree[i] = f(Tree[i << 1], Tree[(i << 1) | 1]); } [MethodImpl(MethodImplOptions.AggressiveInlining)] public void Assign(int idx, T nxt) => Tree[idx + n] = nxt; [MethodImpl(MethodImplOptions.AggressiveInlining)] public void Update(int idx) { int now = idx + n; while (now > 1) { now >>= 1; Tree[now] = f(Tree[now << 1], Tree[now << 1 | 1]); } } [MethodImpl(MethodImplOptions.AggressiveInlining)] public void Query_Update(int idx, T nxt) { Assign(idx, nxt); Update(idx); } [MethodImpl(MethodImplOptions.AggressiveInlining)] public void Query_Update_func(int idx, T y) { Assign(idx, f(Peek(idx), y)); Update(idx); } [MethodImpl(MethodImplOptions.AggressiveInlining)] public T Query_Fold(int l, int r) { int L = n + l; int R = n + r; T vL = ex, vR = ex; while (L < R) { if (L % 2 == 1) { vL = f(vL, Tree[L]); L++; } if (R % 2 == 1) { vR = f(Tree[R - 1], vR); R--; } L >>= 1; R >>= 1; } return f(vL, vR); } [MethodImpl(MethodImplOptions.AggressiveInlining)] public T Peek(int idx) => Tree[idx + n]; [MethodImpl(MethodImplOptions.AggressiveInlining)] public void Display(int len) { for (var i = 0; i < len; i++) Console.Write($"{Tree[i + n]} "); Console.WriteLine(); } [MethodImpl(MethodImplOptions.AggressiveInlining)] public int MaxRight(int l, Func ok) { if (l == len) { return len; } l += n; var sum = ex; do { while (l % 2 == 0) l >>= 1; if (!ok(f(sum, Tree[l]))) { while (l < n) { l <<= 1; if (ok(f(sum, Tree[l]))) { sum = f(sum, Tree[l++]); } } return l - n; } sum = f(sum, Tree[l++]); } while ((l & (-l)) != l); return len; } [MethodImpl(MethodImplOptions.AggressiveInlining)] public int MinLeft(int r, Func ok) { if (r == 0) return 0; r += n; var sum = ex; do { r--; while (r > 1 && (r % 2) != 0) r >>= 1; if (!ok(f(Tree[r], sum))) { while (r < n) { r = (r << 1 | 1); if (ok(f(Tree[r], sum))) { sum = f(Tree[r--], sum); } } return r + 1 - n; } sum = f(Tree[r], sum); } while ((r & (-r)) != r); return 0; } } public class LazySegmentTree { int n, L; X[] Tree; A[] lazy; Func fxx; Func faa; Func fxa; X exx; A exa; public LazySegmentTree(int size, Func funcxx, Func funcaa, Func funcxa, X exval, A exlaz) { n = size; L = (n << 1) - 1; Tree = new X[n << 1]; lazy = new A[n << 1]; fxx = funcxx; faa = funcaa; fxa = funcxa; exx = exval; exa = exlaz; for (var i = 0; i <= L; i++) { Tree[i] = exx; lazy[i] = exa; } } public X eval(int id) => fxa(Tree[id], lazy[id]); [MethodImpl(MethodImplOptions.AggressiveInlining)] public void propagate(int id) { int h = 0; while ((1 << (h + 1)) <= id) h++; for (var n = h; n > 0; n--) { int i = id >> n; Tree[i] = eval(i); lazy[i << 1] = faa(lazy[i << 1], lazy[i]); lazy[i << 1 | 1] = faa(lazy[i << 1 | 1], lazy[i]); lazy[i] = exa; } } [MethodImpl(MethodImplOptions.AggressiveInlining)] public void re_calc(int id) { while (id > 1) { id >>= 1; Tree[id] = fxx(eval(id << 1), eval(id << 1 | 1)); } } public void Range_Update(int l, int r, A op) { int L = n + l, R = n + r; int ll = L / (L & (-L)); int rr = R / (R & (-R)); propagate(ll); propagate(rr - 1); while (L < R) { if ((L & 1) == 1) { lazy[L] = faa(lazy[L], op); L++; } if ((R & 1) == 1) { R--; lazy[R] = faa(lazy[R], op); } L >>= 1; R >>= 1; } re_calc(ll); re_calc(rr - 1); } public X Range_Get(int l, int r) { int L = n + l, R = n + r; X vL = exx, vR = exx; propagate(L / (L & (-L))); propagate(R / (R & (-R)) - 1); while (L < R) { if ((L & 1) == 1) { vL = fxx(vL, eval(L)); L++; } if ((R & 1) == 1) { R--; vR = fxx(eval(R), vR); } L >>= 1; R >>= 1; } return fxx(vL, vR); } public void Point_Update(int idx, X nxt) { int id = idx + n; propagate(id); Tree[id] = nxt; re_calc(id); } /*======================*/ public void Assign(int idx, X nxt) => Tree[n + idx] = nxt; public void Set_All() { for (var i = n - 1; i >= 1; i--) { Tree[i] = fxx(Tree[i << 1], Tree[i << 1 | 1]); lazy[i] = faa(lazy[i << 1], lazy[i << 1 | 1]); } } public X Peek(int idx) => Range_Get(idx, idx + 1); public void Display(int len) { for (var i = 0; i < len; i++) Console.Write($"{Range_Get(i, i + 1)} "); Console.WriteLine(); } public void Displayall() { //木の形で表示、nが2冪でない時は注意 int e = 0; while ((1 << e) <= n) { for (var i = (1 << e); i < (1 << e) + (1 << e); i++) Console.Write($"{Tree[i]}/{lazy[i]} "); Console.WriteLine(); e++; } } } public class StringTools { public static int[] Z_algorithm(string S) { int L = S.Length; var ret = new int[L]; int i = 1, j = 0; ret[0] = L; while (i < L) { while (i + j < L && (S[i + j] == S[j])) j++; ret[i] = j; if (j == 0) { i++; continue; } int k = 1; while (i + k < L && (k + ret[k] < j)) { ret[i + k] = ret[k]; k++; } i += k; j -= k; } return ret; } } public class Rolling_Hash { const ulong m30 = (1UL << 30) - 1; const ulong m31 = (1UL << 31) - 1; const ulong MOD = (1UL << 61) - 1; const ulong Pl = (MOD << 1) << 1; private uint B; private string S; ulong[] hash; ulong[] pw; public Rolling_Hash(string str) { S = str; B = (uint)new Random().Next(1 << 12 + 1, int.MaxValue); int L = S.Length; hash = new ulong[L + 1]; pw = new ulong[L + 1]; hash[0] = 0; pw[0] = 1; for (var i = 0; i < L; i++) { hash[i + 1] = CalcMod(Mul(hash[i], B) + S[i]); pw[i + 1] = CalcMod(Mul(pw[i], B)); } } [MethodImpl(MethodImplOptions.AggressiveInlining)] public ulong GetHashValue(int idx) => hash[idx]; [MethodImpl(MethodImplOptions.AggressiveInlining)]//segment [l,r] public ulong Hash_fold(int l, int r) => CalcMod(Pl + hash[r + 1] - Mul(hash[l], pw[r - l + 1])); [MethodImpl(MethodImplOptions.AggressiveInlining)]//segment[start,start+len-1] public ulong Hash_sub(int start, int len) => CalcMod(Pl + hash[start + len] - Mul(hash[start], pw[len])); [MethodImpl(MethodImplOptions.AggressiveInlining)] public ulong[] GetHashArray() => hash; [MethodImpl(MethodImplOptions.AggressiveInlining)] ulong Mul(ulong a, ulong b) { ulong au = a >> 31; ulong ad = a & m31; ulong bu = b >> 31; ulong bd = b & m31; ulong mid = ad * bu + au * bd; ulong midu = mid >> 30; ulong midd = mid & m30; return au * bu * 2 + midu + (midd << 31) + ad * bd; } [MethodImpl(MethodImplOptions.AggressiveInlining)] ulong CalcMod(ulong x) { ulong xu = x >> 61; ulong xd = x & MOD; ulong res = xu + xd; if (res >= MOD) res -= MOD; return res; } } public class UnionFind { private int[] parent; private int[] rank; private int[] size; public UnionFind(int n) { parent = new int[n]; rank = new int[n]; size = new int[n]; for (var i = 0; i < n; i++) { parent[i] = i; rank[i] = 0; size[i] = 1; } } public int Root(int x) { return parent[x] == x ? x : parent[x] = Root(parent[x]); } public bool SameRoot(int x, int y) { return Root(x) == Root(y); } public void Unite(int x, int y) { x = Root(x); y = Root(y); if (x == y) { return; } if (rank[x] < rank[y]) { parent[x] = y; size[y] += size[x]; size[x] = 0; } else { parent[y] = x; if (rank[x] == rank[y]) { rank[x]++; } size[x] += size[y]; size[y] = 0; } } public int SizeOf(int x) { return size[Root(x)]; } } static class Cin { public static string[] ReadSplit => Console.ReadLine().Split(); public static int[] ReadSplitInt => ConvertAll(ReadSplit, int.Parse); public static long[] ReadSplitLong => ConvertAll(ReadSplit, long.Parse); public static double[] ReadSplit_Double => ConvertAll(ReadSplit, double.Parse); public static string Str => Console.ReadLine(); public static int Int => int.Parse(Console.ReadLine()); public static long Long => long.Parse(Console.ReadLine()); public static double Double => double.Parse(Console.ReadLine()); public static T Conv(string input) { return (T)Convert.ChangeType(input, typeof(T)); } public static void Scanf(out T a) => a = Conv(Console.ReadLine()); public static void Scanf(out T a, out U b) { var q = ReadSplit; a = Conv(q[0]); b = Conv(q[1]); } public static void Scanf(out T a, out U b, out V c) { var q = ReadSplit; a = Conv(q[0]); b = Conv(q[1]); c = Conv(q[2]); } public static void Scanf(out T a, out U b, out V c, out W d) { var q = ReadSplit; a = Conv(q[0]); b = Conv(q[1]); c = Conv(q[2]); d = Conv(q[3]); } public static void Scanf(out T a, out U b, out V c, out W d, out X e) { var q = ReadSplit; a = Conv(q[0]); b = Conv(q[1]); c = Conv(q[2]); d = Conv(q[3]); e = Conv(q[4]); } } static class Cout { public static void OutL(object s) => Console.WriteLine(s); public static void Out_Sep(IEnumerable s) => Console.WriteLine(string.Join(" ", s)); public static void Out_Sep(IEnumerable s, string sep) => Console.WriteLine(string.Join($"{sep}", s)); public static void Out_Sep(params object[] s) => Console.WriteLine(string.Join(" ", s)); public static void Out_One(object s) => Console.Write($"{s} "); public static void Out_One(object s, string sep) => Console.Write($"{s}{sep}"); public static void Endl() => Console.WriteLine(); } public static class Tool { static public void Initialize(ref T[] array, T initialvalue) { array = ConvertAll(array, x => initialvalue); } static public void Swap(ref T a, ref T b) { T keep = a; a = b; b = keep; } static public void Display(T[,] array2d, int n, int m) { for (var i = 0; i < n; i++) { for (var j = 0; j < m; j++) { Console.Write($"{array2d[i, j]} "); } Console.WriteLine(); } } static public long Gcd(long a, long b) { if (a == 0 || b == 0) return Max(a, b); return a % b == 0 ? b : Gcd(b, a % b); } static public long Lcm(long a, long b) => a / Gcd(a, b) * b; static public long ExtGcd(long a, long b, ref long x, ref long y) { if (b == 0) { x = 1; y = 0; return a; } long d = ExtGcd(b, a % b, ref y, ref x); y -= a / b * x; return d; } static public long LPow(int a, int b) => (long)Pow(a, b); static public bool Bit(long x, int dig) => ((1L << dig) & x) != 0; static public int Sig(long a) => a == 0 ? 0 : (int)(a / Abs(a)); } } namespace AtCoder_MOD { public interface IMod { int Mod { get; } // isprime ? } public interface INTTFriendly { int primitive_root { get; } } public readonly struct Mod1000000007 : IMod { public int Mod => 1000000007; } public readonly struct Mod998244353 : IMod, INTTFriendly { public int Mod => 998244353; public int primitive_root => 3; } public struct ModInt where T : IMod { private int value; // 0 <= x < mod 以外でも OK public ModInt(int x) { if (x < 0) x = (x % default(T).Mod) + default(T).Mod; else if (x >= default(T).Mod) x %= default(T).Mod; value = x; } public ModInt(long x) { if (x < 0) x = (x % default(T).Mod) + default(T).Mod; else if (x >= default(T).Mod) x %= default(T).Mod; value = (int)x; } // 0 <= x < mod public ModInt(uint x) => value = (int)x; public static ModInt operator +(ModInt a, ModInt b) { var nv = a.value + b.value; if (nv >= default(T).Mod) nv -= default(T).Mod; return new ModInt((uint)nv); } public static ModInt operator -(ModInt a, ModInt b) { var nv = a.value - b.value; if (nv < 0) nv += default(T).Mod; return new ModInt((uint)nv); } public static ModInt operator *(ModInt a, ModInt b) => new ModInt((uint)(((long)a.value * b.value) % default(T).Mod)); //符号 public static ModInt operator +(ModInt a) => a; public static ModInt operator -(ModInt a) => a.value == 0 ? a : new ModInt((uint)(default(T).Mod - a.value)); public ModInt Pow(long n) { if (n < 0) return Pow(-n).Pow(default(T).Mod - 2); var p = this; var ret = new ModInt(1u); while (n > 0) { if ((n & 1) != 0) ret *= p; p *= p; n >>= 1; } return ret; } public ModInt Inverse() { Debug.Assert(value != 0); int x, u, s, t, k; x = 1; u = 0; t = default(T).Mod; s = value; while (t > 0) { k = s / t; s -= k * t; (s, t) = (t, s); x -= k * u; (x, u) = (u, x); } return new ModInt((uint)(x < 0 ? x + default(T).Mod : x)); } public static ModInt operator /(ModInt a, ModInt b) => (a * b.Inverse()); public static bool operator ==(ModInt a, ModInt b) => a.value == b.value; public static bool operator !=(ModInt a, ModInt b) => a.value != b.value; public override bool Equals(object obj) => obj is ModInt && this == (ModInt)obj; public override int GetHashCode() => value.GetHashCode(); public override string ToString() => value.ToString(); //キャスト public static implicit operator ModInt(int n) => new ModInt(n); public static implicit operator ModInt(long n) => new ModInt(n); public static explicit operator int(ModInt a) => a.value; public static explicit operator long(ModInt a) => a.value; public static int GetMod() => default(T).Mod; } public static class ModCalc where T : IMod { static readonly List> fac = new List>() { 1 }; static List> facinv; static int MAX_N; // Do Use Init(Max_n) Before using other functions public static void Init_Mod(int n) { MAX_N = n; for (int i = 1; i <= n; i++) fac.Add(fac.Last() * i); facinv = new List>() { fac[n].Inverse() }; for (int i = n; i > 0; i--) facinv.Add(facinv.Last() * i); facinv.Reverse(); } public static void Reset() { MAX_N = -1; fac.Clear(); facinv.Clear(); } public static ModInt Fac(int n) { Debug.Assert(n <= MAX_N); return fac[n]; } public static ModInt Finv(int n) { Debug.Assert(n <= MAX_N); return facinv[n]; } public static ModInt Comb(int n, int r) { Debug.Assert(n <= MAX_N); if (n < 0 || r < 0 || n < r) return 0; return fac[n] * facinv[n - r] * facinv[r]; } public static ModInt ModPow(long x, long n) => new ModInt(x).Pow(n); public static ModInt ModPow(int x, long n) => new ModInt((uint)x).Pow(n); public static ModInt ModPow(ModInt x, long n) => x.Pow(n); public static ModInt Inv(long x) => new ModInt(x).Inverse(); public static ModInt Inv(int x) => new ModInt((uint)x).Inverse(); public static List> GetFac() => fac; public static List> GetFacInv() => facinv; } public class MOD_NTT where T : IMod, INTTFriendly { private readonly int mod; private readonly int root; public MOD_NTT() { mod = default(T).Mod; root = default(T).primitive_root; } void NTT(ref ModInt[] a, bool rev = false) { var n = a.Length; if (n == 1) return; var b = new ModInt[n]; var s = new ModInt(root).Pow(rev ? mod - 1 - (mod - 1) / n : (mod - 1) / n); var kp = new List>() { 1 }; int i, j, k, l, r; for (i = 0; i < (n >> 1); ++i) kp.Add(kp.Last() * s); for (i = 1, l = (n >> 1); i < n; i <<= 1, l >>= 1) { for (j = 0, r = 0; j < l; ++j, r += i) { for (k = 0, s = kp[i * j]; k < i; ++k) { var p = a[k + r]; var q = a[k + r + n / 2]; b[k + 2 * r] = (p + q); b[k + 2 * r + i] = ((p - q) * s); } } (a, b) = (b, a); } if (rev) { s = new ModInt(n).Inverse(); for (i = 0; i < n; ++i) a[i] *= s; } } public ModInt[] Convolution_MOD(ModInt[] a, ModInt[] b) { int N = a.Length + b.Length - 1; int t = 1; while (t < N) t <<= 1; var nxa = new ModInt[t]; var nxb = new ModInt[t]; for (var i = 0; i < a.Length; ++i) nxa[i] = a[i]; for (var i = 0; i < b.Length; ++i) nxb[i] = b[i]; NTT(ref nxa); NTT(ref nxb); for (var i = 0; i < t; i++) nxa[i] *= nxb[i]; NTT(ref nxa, true); return nxa[0..N]; } public ModInt[] Convolution_MOD(long[] a, long[] b) { int N = a.Length + b.Length - 1; int t = 1; while (t < N) t <<= 1; var nxa = new ModInt[t]; var nxb = new ModInt[t]; for (var i = 0; i < a.Length; ++i) nxa[i] = a[i]; for (var i = 0; i < b.Length; ++i) nxb[i] = b[i]; NTT(ref nxa); NTT(ref nxb); for (var i = 0; i < t; i++) nxa[i] *= nxb[i]; NTT(ref nxa, true); return nxa[0..N]; } } //次数固定、NTT対応modのみ public struct FormalPowerSeries where T : IMod, INTTFriendly { int n; ModInt[] P; static readonly MOD_NTT C = new MOD_NTT(); public FormalPowerSeries(int n) { this.n = n; P = new ModInt[n + 1]; } public int Length => n; public ModInt this[int id] { set { Debug.Assert(0 <= id && id <= n); P[id] = value; } get { Debug.Assert(0 <= id && id <= n); return P[id]; } } //Add //O(min(n,m)) public static FormalPowerSeries operator +(FormalPowerSeries F, FormalPowerSeries G) { int m = Math.Min(F.Length, G.Length); for (var i = 0; i <= m; i++) F[i] += G[i]; return F; } //O(1) public static FormalPowerSeries operator +(FormalPowerSeries F, ModInt a) { F[0] += a; return F; } //Subtract //O(min(n,m)) public static FormalPowerSeries operator -(FormalPowerSeries F, FormalPowerSeries G) { int m = Math.Min(F.Length, G.Length); for (var i = 0; i <= m; i++) F[i] -= G[i]; return F; } //O(1) public static FormalPowerSeries operator -(FormalPowerSeries F, ModInt a) { F[0] -= a; return F; } // Multiply //O(nlog(n)) //下位 n 項のみ残すことに注意 public static FormalPowerSeries operator *(FormalPowerSeries F, FormalPowerSeries G) { F.P = C.Convolution_MOD(F.P, G.P)[0..(F.n + 1)]; return F; } //O(n) public static FormalPowerSeries operator *(FormalPowerSeries F, ModInt a) { for (var i = 0; i <= F.n; i++) F[i] *= a; return F; } //Divide //Todo F/=G //O(n+log(mod)) public static FormalPowerSeries operator /(FormalPowerSeries F, ModInt a) { var inv = a.Inverse(); for (var i = 0; i <= F.n; i++) F[i] *= inv; return F; } } }