結果
| 問題 |
No.1300 Sum of Inversions
|
| コンテスト | |
| ユーザー |
 keymoon
|
| 提出日時 | 2020-11-27 21:47:17 |
| 言語 | C#(csc) (csc 3.9.0) |
| 結果 |
AC
|
| 実行時間 | 997 ms / 2,000 ms |
| コード長 | 6,197 bytes |
| コンパイル時間 | 5,221 ms |
| コンパイル使用メモリ | 119,992 KB |
| 実行使用メモリ | 70,512 KB |
| 最終ジャッジ日時 | 2024-07-26 12:12:05 |
| 合計ジャッジ時間 | 27,510 ms |
|
ジャッジサーバーID （参考情報） |
judge2 / judge3 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 34 |
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.IO;
using System.Linq;
using System.Numerics;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using static System.Math;
using MethodImplAttribute = System.Runtime.CompilerServices.MethodImplAttribute;
using MethodImplOptions = System.Runtime.CompilerServices.MethodImplOptions;
public static class P
{
public static void Main()
{
int n = int.Parse(Console.ReadLine());
var a = Console.ReadLine().Split().Select(int.Parse).ToArray();
var ordered = a.Distinct().OrderBy(x => x).ToArray();
var dic = ordered.Select((elem, ind) => (elem, ind)).ToDictionary(x => x.elem, x => x.ind);
a = a.Select(x => dic[x]).ToArray();
(ModInt val, ModInt cnt)[] lRes = new (ModInt val, ModInt cnt)[n];
{
var segTree = new SegmentTree<(ModInt, ModInt)>(ordered.Length, (0, 0), (x, y) => (x.Item1 + y.Item1, x.Item2 + y.Item2));
for (int i = 0; i < lRes.Length; i++)
{
lRes[i] = segTree.Query(a[i] + 1, ordered.Length - 1);
segTree.Operate(a[i], (ordered[a[i]], 1));
}
}
(ModInt val, ModInt cnt)[] rRes = new (ModInt val, ModInt cnt)[n];
{
var segTree = new SegmentTree<(ModInt, ModInt)>(ordered.Length, (0, 0), (x, y) => (x.Item1 + y.Item1, x.Item2 + y.Item2));
for (int i = rRes.Length - 1; i >= 0; i--)
{
rRes[i] = segTree.Query(0, a[i] - 1);
segTree.Operate(a[i], (ordered[a[i]], 1));
}
}
ModInt res = 0;
for (int i = 0; i < n; i++)
{
var (lVal, lCnt) = lRes[i];
var (rVal, rCnt) = rRes[i];
var sum = lVal * rCnt + rVal * lCnt + ordered[a[i]] * lCnt * rCnt;
res += sum;
}
Console.WriteLine(res);
}
}
class SegmentTree<T>
{
public int Size { get; private set; }
T Identity;
T[] Data;
Func<T, T, T> Merge;
int LeafCount;
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public SegmentTree(int size, T identity, Func<T, T, T> merge)
{
Init(size, identity, merge);
for (int i = 1; i < Data.Length; i++) Data[i] = identity;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public SegmentTree(T[] elems, T identity, Func<T, T, T> merge)
{
Init(elems.Length, identity, merge);
elems.CopyTo(Data, LeafCount);
for (int i = elems.Length + LeafCount; i < Data.Length; i++) Data[i] = identity;
for (int i = LeafCount - 1; i >= 1; i--) Data[i] = Merge(Data[i << 1], Data[(i << 1) | 1]);
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private void Init(int size, T identity, Func<T, T, T> merge)
{
Size = size;
Identity = identity;
Merge = merge;
LeafCount = 1;
while (LeafCount < size) LeafCount <<= 1;
Data = new T[LeafCount << 1];
}
public T this[int index]
{
[MethodImpl(MethodImplOptions.AggressiveInlining)]
get { return Data[LeafCount + index]; }
[MethodImpl(MethodImplOptions.AggressiveInlining)]
set { Update(index, value); }
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public void Update(int i, T x) { Data[i += LeafCount] = x; while (0 < (i >>= 1)) Data[i] = Merge(Data[i << 1], Data[(i << 1) | 1]); }
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public void Operate(int i, T x) { i += LeafCount; Data[i] = Merge(Data[i], x); while (0 < (i >>= 1)) Data[i] = Merge(Data[i << 1], Data[(i << 1) | 1]); }
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public T Query(int l, int r)
{
T lRes = Identity, rRes = Identity;
for (l += LeafCount, r += LeafCount; l <= r; l = (l + 1) >> 1, r = (r - 1) >> 1)
{
if ((l & 1) == 1) lRes = Merge(lRes, Data[l]); if ((r & 1) == 0) rRes = Merge(Data[r], rRes);
}
return Merge(lRes, rRes);
}
}
struct ModInt
{
public const int Mod = 998244353;
const long POSITIVIZER = ((long)Mod) << 31;
long Data;
public ModInt(long data) { if ((Data = data % Mod) < 0) Data += Mod; }
public static implicit operator long(ModInt modInt) => modInt.Data;
public static implicit operator ModInt(long val) => new ModInt(val);
public static ModInt operator +(ModInt a, int b) => new ModInt() { Data = (a.Data + b + POSITIVIZER) % Mod };
public static ModInt operator +(ModInt a, long b) => new ModInt(a.Data + b);
public static ModInt operator +(ModInt a, ModInt b) { long res = a.Data + b.Data; return new ModInt() { Data = res >= Mod ? res - Mod : res }; }
public static ModInt operator -(ModInt a, int b) => new ModInt() { Data = (a.Data - b + POSITIVIZER) % Mod };
public static ModInt operator -(ModInt a, long b) => new ModInt(a.Data - b);
public static ModInt operator -(ModInt a, ModInt b) { long res = a.Data - b.Data; return new ModInt() { Data = res < 0 ? res + Mod : res }; }
public static ModInt operator *(ModInt a, int b) => new ModInt(a.Data * b);
public static ModInt operator *(ModInt a, long b) => a * new ModInt(b);
public static ModInt operator *(ModInt a, ModInt b) => new ModInt() { Data = a.Data * b.Data % Mod };
public static ModInt operator /(ModInt a, ModInt b) => new ModInt() { Data = a.Data * GetInverse(b) % Mod };
public static bool operator ==(ModInt a, ModInt b) => a.Data == b.Data;
public static bool operator !=(ModInt a, ModInt b) => a.Data != b.Data;
public override string ToString() => Data.ToString();
public override bool Equals(object obj) => (ModInt)obj == this;
public override int GetHashCode() => (int)Data;
static long GetInverse(long a)
{
long div, p = Mod, x1 = 1, y1 = 0, x2 = 0, y2 = 1;
while (true)
{
if (p == 1) return x2 + Mod; div = a / p; x1 -= x2 * div; y1 -= y2 * div; a %= p;
if (a == 1) return x1 + Mod; div = p / a; x2 -= x1 * div; y2 -= y1 * div; p %= a;
}
}
}