#584654 (C++14) No.1193 Penguin Sequence

• 問題: No.1193 Penguin Sequence
• ユーザー: kotatsugame
• 提出日時: 2020-11-27 08:39:07
• 言語: C++14 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 144 ms / 2,000 ms
• コード長: 3,607 bytes
• コンパイル時間: 869 ms
• コンパイル使用メモリ: 79,140 KB
• 実行使用メモリ: 7,424 KB
• 最終ジャッジ日時: 2024-07-23 21:23:08
• 合計ジャッジ時間: 7,828 ms
• ジャッジサーバーID （参考情報）: judge3 / judge1

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	112 ms; 7,168 KB
testcase_01	AC	142 ms; 7,296 KB
testcase_02	AC	142 ms; 7,296 KB
testcase_03	AC	143 ms; 7,296 KB
testcase_04	AC	143 ms; 7,296 KB
testcase_05	AC	144 ms; 7,168 KB
testcase_06	AC	143 ms; 7,168 KB
testcase_07	AC	142 ms; 7,296 KB
testcase_08	AC	142 ms; 7,296 KB
testcase_09	AC	142 ms; 7,296 KB
testcase_10	AC	142 ms; 7,168 KB
testcase_11	AC	80 ms; 5,632 KB
testcase_12	AC	80 ms; 5,504 KB
testcase_13	AC	123 ms; 6,656 KB
testcase_14	AC	115 ms; 6,528 KB
testcase_15	AC	135 ms; 7,040 KB
testcase_16	AC	105 ms; 7,424 KB
testcase_17	AC	2 ms; 5,376 KB
testcase_18	AC	13 ms; 5,376 KB
testcase_19	AC	142 ms; 7,296 KB
testcase_20	AC	111 ms; 6,272 KB
testcase_21	AC	89 ms; 5,632 KB
testcase_22	AC	16 ms; 5,376 KB
testcase_23	AC	74 ms; 5,376 KB
testcase_24	AC	64 ms; 5,376 KB
testcase_25	AC	29 ms; 5,376 KB
testcase_26	AC	9 ms; 5,376 KB
testcase_27	AC	120 ms; 6,784 KB
testcase_28	AC	83 ms; 5,504 KB
testcase_29	AC	122 ms; 6,528 KB
testcase_30	AC	42 ms; 5,376 KB
testcase_31	AC	35 ms; 5,376 KB
testcase_32	AC	95 ms; 5,888 KB
testcase_33	AC	66 ms; 5,376 KB
testcase_34	AC	54 ms; 5,376 KB
testcase_35	AC	67 ms; 5,376 KB
testcase_36	AC	51 ms; 5,376 KB
testcase_37	AC	115 ms; 6,528 KB
testcase_38	AC	2 ms; 5,376 KB
testcase_39	AC	2 ms; 5,376 KB
testcase_40	AC	2 ms; 5,376 KB

コンパイルメッセージ

a.cpp:12:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]

ソースコード

#line 1 "a.cpp"
#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
#line 3 "/home/kotatsugame/library/math/modint.cpp"
#include<utility>
template<int m>
struct modint{
	unsigned int x;
	constexpr modint()noexcept:x(){}
	template<typename T>
	constexpr modint(T x_)noexcept:x((x_%=m)<0?x_+m:x_){}
	constexpr unsigned int val()const noexcept{return x;}
	constexpr modint&operator++()noexcept{if(++x==m)x=0;return*this;}
	constexpr modint&operator--()noexcept{if(x==0)x=m;--x;return*this;}
	constexpr modint operator++(int)noexcept{modint res=*this;++*this;return res;}
	constexpr modint operator--(int)noexcept{modint res=*this;--*this;return res;}
	constexpr modint&operator+=(const modint&a)noexcept{x+=a.x;if(x>=m)x-=m;return*this;}
	constexpr modint&operator-=(const modint&a)noexcept{if(x<a.x)x+=m;x-=a.x;return*this;}
	constexpr modint&operator*=(const modint&a)noexcept{x=(unsigned long long)x*a.x%m;return*this;}
	constexpr modint&operator/=(const modint&a)noexcept{return*this*=a.inv();}
	constexpr modint operator+()const noexcept{return*this;}
	constexpr modint operator-()const noexcept{return modint()-*this;}
	constexpr modint pow(long long n)const noexcept
	{
		if(n<0)return pow(-n).inv();
		modint x=*this,r=1;
		for(;n;x*=x,n>>=1)if(n&1)r*=x;
		return r;
	}
	constexpr modint inv()const noexcept
	{
		int s=x,t=m,x=1,u=0;
		while(t)
		{
			int k=s/t;
			s-=k*t;
			swap(s,t);
			x-=k*u;
			swap(x,u);
		}
		return modint(x);
	}
	friend constexpr modint operator+(const modint&a,const modint&b){return modint(a)+=b;}
	friend constexpr modint operator-(const modint&a,const modint&b){return modint(a)-=b;}
	friend constexpr modint operator*(const modint&a,const modint&b){return modint(a)*=b;}
	friend constexpr modint operator/(const modint&a,const modint&b){return modint(a)/=b;}
	friend constexpr bool operator==(const modint&a,const modint&b){return a.x==b.x;}
	friend constexpr bool operator!=(const modint&a,const modint&b){return a.x!=b.x;}
	friend ostream&operator<<(ostream&os,const modint&a){return os<<a.x;}
	friend istream&operator>>(istream&is,modint&a){long long v;is>>v;a=modint(v);return is;}
};
#line 1 "/home/kotatsugame/library/datastructure/BIT.cpp"
//1-indexed
#line 3 "/home/kotatsugame/library/datastructure/BIT.cpp"
template<typename T>
struct BIT{
	int n;
	vector<T>bit;
	BIT(int n_=0):n(n_),bit(n_+1){}
	T sum(int i)
	{
		T ans=0;
		for(;i>0;i-=i&-i)ans+=bit[i];
		return ans;
	}
	void add(int i,T a)
	{
		if(i==0)return;
		for(;i<=n;i+=i&-i)bit[i]+=a;
	}
	int lower_bound(T k)//k<=sum(ret)
	{
		if(k<=0)return 0;
		int ret=0,i=1;
		while((i<<1)<=n)i<<=1;
		for(;i;i>>=1)
			if(ret+i<=n&&bit[ret+i]<k)k-=bit[ret+=i];
		return ret+1;
	}
};
#line 7 "a.cpp"
using mint=modint<998244353>;
int N;
int A[2<<17];
mint fac[2<<17],inv[2<<17];
mint comb(int a,int b){return fac[a]*inv[b]*inv[a-b];}
main()
{
	cin>>N;
	fac[0]=1;
	for(int i=1;i<=N;i++)fac[i]=fac[i-1]*i;
	inv[N]=1/fac[N];
	for(int i=N;i--;)inv[i]=inv[i+1]*(i+1);
	vector<int>v(N);
	for(int i=0;i<N;i++)
	{
		cin>>A[i];
		v[i]=A[i];
	}
	if(N==1)
	{
		cout<<0<<endl;
		return 0;
	}
	sort(v.begin(),v.end());
	v.erase(unique(v.begin(),v.end()),v.end());
	mint x,y;
	BIT<int>P(N);
	for(int i=0;i<N;i++)
	{
		A[i]=upper_bound(v.begin(),v.end(),A[i])-v.begin();
		x+=i-P.sum(A[i]);
		P.add(A[i],1);
	}
	for(int i=0;i<N;i++)
	{
		y+=N-P.sum(A[i]);
	}
	mint all=1;
	for(int i=1;i<=N;i++)all*=comb(N,i);
	mint xp;
	for(int i=2;i<=N;i++)
	{
		xp+=mint(i)*(i-1);
	}
	xp/=mint(N)*(N-1);
	mint yp,zp;
	for(int i=1;i<=N;i++)
	{
		yp+=zp*i;
		zp+=i;
	}
	yp/=mint(N)*N;
	cout<<all*(xp*x+yp*y)<<endl;
}