提出 #41775072

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ソースコード 拡げる

#include<bits/stdc++.h>
using namespace std;
const int md=998244353,N=600010,g3=(md+1)/3;
typedef long long LL;
int n,m,k,a[N],A[N],G[N],b[N],f[N];
inline void upd(int&a){a+=a>>31&md;}
inline int ksm(int a,int b){
	int r=1;
	for(;b;b>>=1,a=(LL)a*a%md)if(b&1)r=(LL)r*a%md;return r;
}
namespace poly{
	int lim,rev[N],inv[N];
	inline int poly_start(){
		inv[1]=1;
		for(int i=2;i<N;++i)inv[i]=(md-md/i)*(LL)inv[md%i]%md;
		return 1;
	}
	int __START__=poly_start();
	inline void init(int n){
		int l=-1;
		for(lim=1;lim<n;lim<<=1)++l;
		for(int i=1;i<lim;++i)rev[i]=(rev[i>>1]>>1)|((i&1)<<l);
	}
	void NTT(int*a,int f){
		for(int i=1;i<lim;++i)if(i<rev[i])std::swap(a[i],a[rev[i]]);
		for(int i=1;i<lim;i<<=1){
			const int gi=ksm(f?3:g3,(md-1)/(i<<1));
			for(int j=0;j<lim;j+=i<<1)
			for(int k=0,g=1;k<i;++k,g=(LL)g*gi%md){
				const int x=a[j+k],y=a[j+k+i]*(LL)g%md;
				upd(a[j+k]+=y-md),upd(a[j+k+i]=x-y);
			}
		}
		if(!f){
			const LL iv=inv[lim];
			for(int i=0;i<lim;++i)a[i]=a[i]*iv%md;
		}
	}
	void INV(const int*a,int*B,int n){
		if(n==1)*B=ksm(*a,md-2);else{
			INV(a,B,n+1>>1);
			init(n<<1);
			static int A[N];
			for(int i=0;i<n;++i)A[i]=a[i];
			for(int i=n;i<lim;++i)A[i]=0;
			NTT(A,1),NTT(B,1);
			for(int i=0;i<lim;++i)B[i]=B[i]*((2-(LL)A[i]*B[i]%md+md)%md)%md;
			NTT(B,0);
			for(int i=n;i<lim;++i)B[i]=0;
		}
	}
	void dao(const int*a,int*G,int n){
		G[n-1]=0;
		for(int i=1;i<n;++i)
		G[i-1]=(LL)i*a[i]%md;
	}
	void INT(const int*a,int*G,int n){
		*G=0;
		for(int i=n-1;~i;--i)G[i+1]=a[i]*(LL)inv[i+1]%md;
	}
	void LN(const int*a,int*B,int n){
		static int F[N];
		dao(a,F,n),INV(a,B,n);
		init(n<<1);
		for(int i=n;i<lim;++i)B[i]=F[i]=0;
		NTT(F,1),NTT(B,1);
		for(int i=0;i<lim;++i)F[i]=(LL)B[i]*F[i]%md;
		NTT(F,0);
		INT(F,B,n);
		for(int i=n;i<lim;++i)B[i]=0;
	}
	void EXP(const int*a,int*F,int n){
		if(n==1)*F=1;else{
			EXP(a,F,n+1>>1);
			static int F0[N],A[N];
			for(int i=0;i<=n<<1;++i)F0[i]=0,A[i]=a[i];
			LN(F,F0,n);
			init(n<<1);
			for(int i=n;i<lim;++i)A[i]=0;
			NTT(A,1),NTT(F0,1),NTT(F,1);
			for(int i=0;i<lim;++i)F[i]=F[i]*(A[i]+1LL-F0[i]+md)%md;
			NTT(F,0);
			for(int i=n;i<lim;++i)F[i]=0;
		}
	}
}
int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);cout.tie(0);
	cin>>n>>m;f[0]=1;
	for(int i=1;i<=n;i++)f[i]=1ll*f[i-1]*i%md;
	for(int i=0;i<m;i++)cin>>b[i],a[b[i]-1]=ksm(f[b[i]-1],md-2);
	poly::LN(a,A,n);
	for(int i=0;i<n;++i)A[i]=A[i]*(LL)n%md;
	for(int i=0;i<n;++i)a[i]=0;
	poly::EXP(A,a,n);
	cout<<1ll*a[n-2]*f[n-2]%md<<'\n';
	return 0;
}

提出情報

コンパイルエラー

./Main.cpp: In function ‘int ksm(int, int)’:
./Main.cpp:9:2: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation]
    9 |  for(;b;b>>=1,a=(LL)a*a%md)if(b&1)r=(LL)r*a%md;return r;
      |  ^~~
./Main.cpp:9:48: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘for’
    9 |  for(;b;b>>=1,a=(LL)a*a%md)if(b&1)r=(LL)r*a%md;return r;
      |                                                ^~~~~~
./Main.cpp: In function ‘void poly::INV(const int*, int*, int)’:
./Main.cpp:41:13: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses]
   41 |    INV(a,B,n+1>>1);
      |            ~^~
./Main.cpp: In function ‘void poly::EXP(const int*, int*, int)’:
./Main.cpp:74:13: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses]
   74 |    EXP(a,F,n+1>>1);
      |            ~^~

ジャッジ結果