結果
| 問題 |
No.1102 Remnants
|
| コンテスト | |
| ユーザー |
 takytank
|
| 提出日時 | 2020-07-04 00:22:58 |
| 言語 | C#(csc) (csc 3.9.0) |
| 結果 |
AC
|
| 実行時間 | 147 ms / 2,000 ms |
| コード長 | 10,143 bytes |
| コンパイル時間 | 926 ms |
| コンパイル使用メモリ | 120,028 KB |
| 実行使用メモリ | 42,112 KB |
| 最終ジャッジ日時 | 2024-09-17 05:16:25 |
| 合計ジャッジ時間 | 3,696 ms |
|
ジャッジサーバーID （参考情報） |
judge3 / judge2 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 25 |
コンパイルメッセージ
Microsoft (R) Visual C# Compiler version 3.9.0-6.21124.20 (db94f4cc) Copyright (C) Microsoft Corporation. All rights reserved.
ソースコード
using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.IO;
using System.Linq;
using System.Numerics;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
namespace AtCoder
{
public class Program
{
static void Main()
{
var cin = new Scanner();
int n = cin.Int();
int k = cin.Int();
var a = cin.ArrayInt(n);
ModCounting.InitializeFactorial(n + 1, true);
var nck = new ModInt[n + 1];
nck[0] = 1;
for (int i = 0; i < n; i++) {
nck[i + 1] = nck[i] * (k + i + 1);
nck[i + 1] *= ModCounting.Inverse(i + 1);
}
ModInt ans = 0;
for (int i = 0; i < n; i++) {
ans += nck[i] * nck[n - 1 - i] * a[i];
}
Console.WriteLine(ans);
}
}
public static class ModCounting
{
private const long p_ = ModInt.P;
private static ModInt[] factorial_;
private static ModInt[] inverseFactorial_;
private static ModInt[] inverse_;
public static void InitializeFactorial(long max, bool withInverse = false)
{
if (withInverse) {
factorial_ = new ModInt[max + 1];
inverseFactorial_ = new ModInt[max + 1];
inverse_ = new ModInt[max + 1];
factorial_[0] = factorial_[1] = 1;
inverseFactorial_[0] = inverseFactorial_[1] = 1;
inverse_[1] = 1;
for (int i = 2; i <= max; i++) {
factorial_[i] = factorial_[i - 1] * i;
inverse_[i] = p_ - inverse_[p_ % i] * (p_ / i);
inverseFactorial_[i] = inverseFactorial_[i - 1] * inverse_[i];
}
} else {
factorial_ = new ModInt[max + 1];
inverseFactorial_ = new ModInt[max + 1];
factorial_[0] = factorial_[1] = 1;
for (int i = 2; i <= max; i++) {
factorial_[i] = factorial_[i - 1] * i;
}
inverseFactorial_[max] = new ModInt(1) / factorial_[max];
for (long i = max - 1; i >= 0; i--) {
inverseFactorial_[i] = inverseFactorial_[i + 1] * (i + 1);
}
}
}
public static ModInt Factorial(long n)
{
if (n < 0) {
return 0;
}
return factorial_[n];
}
public static ModInt InverseFactorial(long n)
{
if (n < 0) {
return 0;
}
return inverseFactorial_[n];
}
public static ModInt Inverse(long n)
{
if (n < 0) {
return 0;
}
return inverse_[n];
}
public static ModInt Permutation(long n, long k)
{
if (n < k || (n < 0 || k < 0)) {
return 0;
}
return factorial_[n] * inverseFactorial_[n - k];
}
public static ModInt RepeatedPermutation(long n, long k)
{
long ret = 1;
for (k %= p_ - 1; k > 0; k >>= 1, n = n * n % p_) {
if ((k & 1) == 1) {
ret = ret * n % p_;
}
}
return ret;
}
public static ModInt Combination(long n, long k)
{
if (n < k || (n < 0 || k < 0)) {
return 0;
}
return factorial_[n] * inverseFactorial_[k] * inverseFactorial_[n - k];
}
public static ModInt CombinationK(long n, long k)
{
ModInt ret = 1;
for (int i = 0; i < k; i++) {
ret *= (n - i);
ret *= inverse_[i + 1];
}
return ret;
}
public static ModInt HomogeneousProduct(long n, long k)
{
if (n < 0 || k < 0) {
return 0;
}
return Combination(n + k - 1, k);
}
}
public struct ModInt
{
public const long P = 1000000007;
//public const long P = 998244353;
public static ModInt Inverse(ModInt value) => Pow(value, P - 2);
public static ModInt Pow(ModInt value, long k) => Pow(value.value_, k);
public static ModInt Pow(long value, long k)
{
long ret = 1;
for (k %= P - 1; k > 0; k >>= 1, value = value * value % P) {
if ((k & 1) == 1) {
ret = ret * value % P;
}
}
return new ModInt(ret);
}
private long value_;
public ModInt(long value)
=> value_ = value;
public ModInt(long value, bool mods)
{
if (mods) {
value %= P;
if (value < 0) {
value += P;
}
}
value_ = value;
}
public static ModInt operator +(ModInt lhs, ModInt rhs)
{
lhs.value_ = (lhs.value_ + rhs.value_) % P;
return lhs;
}
public static ModInt operator +(long lhs, ModInt rhs)
{
rhs.value_ = (lhs + rhs.value_) % P;
return rhs;
}
public static ModInt operator +(ModInt lhs, long rhs)
{
lhs.value_ = (lhs.value_ + rhs) % P;
return lhs;
}
public static ModInt operator -(ModInt lhs, ModInt rhs)
{
lhs.value_ = (P + lhs.value_ - rhs.value_) % P;
return lhs;
}
public static ModInt operator -(long lhs, ModInt rhs)
{
rhs.value_ = (P + lhs - rhs.value_) % P;
return rhs;
}
public static ModInt operator -(ModInt lhs, long rhs)
{
lhs.value_ = (P + lhs.value_ - rhs) % P;
return lhs;
}
public static ModInt operator *(ModInt lhs, ModInt rhs)
{
lhs.value_ = lhs.value_ * rhs.value_ % P;
return lhs;
}
public static ModInt operator *(long lhs, ModInt rhs)
{
rhs.value_ = lhs * rhs.value_ % P;
return rhs;
}
public static ModInt operator *(ModInt lhs, long rhs)
{
lhs.value_ = lhs.value_ * rhs % P;
return lhs;
}
public static ModInt operator /(ModInt lhs, ModInt rhs)
{
long exp = P - 2;
while (exp > 0) {
if (exp % 2 > 0) {
lhs *= rhs;
}
rhs *= rhs;
exp /= 2;
}
return lhs;
}
public static implicit operator ModInt(long n) => new ModInt(n, true);
public long ToLong() => value_;
public override string ToString() => value_.ToString();
}
public class HashMap<TKey, TValue> : Dictionary<TKey, TValue>
{
private readonly Func<TKey, TValue> initialzier_;
public HashMap(Func<TKey, TValue> initialzier)
: base()
{
initialzier_ = initialzier;
}
public HashMap(Func<TKey, TValue> initialzier, int capacity)
: base(capacity)
{
initialzier_ = initialzier;
}
new public TValue this[TKey key]
{
get
{
if (ContainsKey(key) == false) {
base[key] = initialzier_(key);
}
return base[key];
}
set { base[key] = value; }
}
}
public static class Helper
{
public static void UpdateMin<T>(ref T target, T value) where T : IComparable<T>
=> target = target.CompareTo(value) > 0 ? value : target;
public static void UpdateMin<T>(ref T target, T value, Action<T> onUpdated) where T : IComparable<T>
{
if (target.CompareTo(value) > 0) {
target = value;
onUpdated(value);
}
}
public static void UpdateMax<T>(ref T target, T value) where T : IComparable<T>
=> target = target.CompareTo(value) < 0 ? value : target;
public static void UpdateMax<T>(ref T target, T value, Action<T> onUpdated) where T : IComparable<T>
{
if (target.CompareTo(value) < 0) {
target = value;
onUpdated(value);
}
}
public static T[] Array<T>(int n, Func<int, T> init)
=> Enumerable.Range(0, n).Select(x => init(x)).ToArray();
public static List<T> List<T>(int n, Func<int, T> init)
=> Enumerable.Range(0, n).Select(x => init(x)).ToList();
public static T[,] Array2<T>(int n, int m, T init)
{
var array = new T[n, m];
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
array[i, j] = init;
}
}
return array;
}
public static T[,] Array2<T>(int n, int m, Func<int, int, T> initializer)
{
var array = new T[n, m];
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
array[i, j] = initializer(i, j);
}
}
return array;
}
public static T[,,] Array3<T>(int n1, int n2, int n3, T init)
{
var array = new T[n1, n2, n3];
for (int i1 = 0; i1 < n1; i1++) {
for (int i2 = 0; i2 < n2; i2++) {
for (int i3 = 0; i3 < n3; i3++) {
array[i1, i2, i3] = init;
}
}
}
return array;
}
private static readonly int[] delta4_ = { 1, 0, -1, 0, 1 };
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static void DoAt4(int i, int j, int imax, int jmax, Action<int, int> action)
{
for (int dn = 0; dn < 4; dn++) {
int d4i = i + delta4_[dn];
int d4j = j + delta4_[dn + 1];
if ((uint)d4i < (uint)imax && (uint)d4j < (uint)jmax) {
action(d4i, d4j);
}
}
}
private static readonly int[] delta8_ = { 1, 0, -1, 0, 1, 1, -1, -1, 1 };
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static void DoAt8(int i, int j, int imax, int jmax, Action<int, int> action)
{
for (int dn = 0; dn < 8; dn++) {
int d8i = i + delta8_[dn];
int d8j = j + delta8_[dn + 1];
if ((uint)d8i < (uint)imax && (uint)d8j < (uint)jmax) {
action(d8i, d8j);
}
}
}
}
public class Scanner
{
private readonly char[] delimiter_ = new char[] { ' ' };
private readonly string filePath_;
private readonly Func<string> reader_;
private string[] buf_;
private int index_;
public Scanner(string file = "")
{
if (string.IsNullOrWhiteSpace(file)) {
reader_ = Console.ReadLine;
} else {
filePath_ = file;
var fs = new StreamReader(file);
reader_ = fs.ReadLine;
}
buf_ = new string[0];
index_ = 0;
}
public string NextLine() => reader_();
public string Next()
{
if (index_ < buf_.Length) {
return buf_[index_++];
}
string st = reader_();
while (st == "") {
st = reader_();
}
buf_ = st.Split(delimiter_, StringSplitOptions.RemoveEmptyEntries);
if (buf_.Length == 0) {
return Next();
}
index_ = 0;
return buf_[index_++];
}
public int Int() => int.Parse(Next());
public long Long() => long.Parse(Next());
public double Double() => double.Parse(Next());
public int[] ArrayInt(int N, int add = 0)
{
int[] Array = new int[N];
for (int i = 0; i < N; i++) {
Array[i] = Int() + add;
}
return Array;
}
public long[] ArrayLong(int N, long add = 0)
{
long[] Array = new long[N];
for (int i = 0; i < N; i++) {
Array[i] = Long() + add;
}
return Array;
}
public double[] ArrayDouble(int N, double add = 0)
{
double[] Array = new double[N];
for (int i = 0; i < N; i++) {
Array[i] = Double() + add;
}
return Array;
}
public void Save(string text)
{
if (string.IsNullOrWhiteSpace(filePath_)) {
return;
}
File.WriteAllText(filePath_ + "_output.txt", text);
}
}
}