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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#463889#6349. Is This FFT?zyz07WA 6268ms76364kbC++174.1kb2024-07-05 15:39:262024-07-05 15:39:26

Judging History

你现在查看的是最新测评结果

  • [2024-07-05 15:39:26]
  • 评测
  • 测评结果:WA
  • 用时:6268ms
  • 内存:76364kb
  • [2024-07-05 15:39:26]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define For(Ti,Ta,Tb) for(auto Ti=(Ta);Ti<=(Tb);++Ti)
#define Dec(Ti,Ta,Tb) for(auto Ti=(Ta);Ti>=(Tb);--Ti)
#define range(Tx) begin(Tx),end(Tx)
#define debug(...) fprintf(stderr,__VA_ARGS__)
using ll=long long;
struct FastMod{
	using ull=unsigned long long;
	using L=__int128;
	ull b,m;
	FastMod(ull b):b(b),m(ull((L(1)<<64)/b)){}
	ull reduce(ull a) const{
		ull q=(ull)((L(m)*a)>>64),r=a-q*b;
		return r>=b?r-b:r;
	}
}Mod(2);
template<typename T,typename=enable_if_t<is_integral_v<T>>>
T operator%(T x,const FastMod& Mod){
	return Mod.reduce(x);
}
template<typename T,typename=enable_if_t<is_integral_v<T>>>
T& operator%=(T& x,const FastMod& Mod){
	return x=Mod.reduce(x);
}
ll power(ll x,ll y){
	ll r=1;
	for(;y;y>>=1,x=x*x%Mod){
		if(y&1) r=r*x%Mod;
	}
	return r;
}
int C2(int x){
	return x*(x-1)>>1;
}
namespace NTT{
	unsigned P;
	int G;
	const int N=1<<16;
	template<typename T>
	void mod(T& x){
		x=(x>=P?x-P:x);
	}
	unsigned long long W[N],IW[N];
	void init(int n){
		const int IG=power(G,P-2);
		for(int l=2,mid=1;l<=n;l<<=1,mid<<=1)
			for(int i=0,wn=power(G,(P-1)/l),iwn=power(IG,(P-1)/l),w=1,iw=1;i<mid;i++)
				W[mid+i]=w,IW[mid+i]=iw,w=((ll)w*wn)%P,iw=((ll)iw*iwn)%P;
	}
	void dft(unsigned long long* f,int n){
		unsigned long long x,y;
		for(int l=n,mid=l>>1;l>=2;l>>=1,mid>>=1)
			for(int p=0;p<n;p+=l){
				#pragma GCC unroll 16
				for(int i=0;i<mid;i++)
					x=f[p+i],y=f[p+mid+i],mod(f[p+i]+=y),f[p+mid+i]=W[mid+i]*(P+x-y)%Mod;
			}
	}
	void idft(unsigned long long* f,int n){
		unsigned long long x,y;
		for(int l=2,mid=1;l<=n;l<<=1,mid<<=1)
			for(int p=0;p<n;p+=l){
				#pragma GCC unroll 16
				for(int i=0;i<mid;i++)
					x=f[p+i],y=f[p+mid+i]*IW[mid+i]%Mod,mod(f[p+i]+=y),mod(f[p+i+mid]=P+x-y);
			}
		for(int i=0,invn=power(n,P-2);i<n;i++){
			f[i]=f[i]*invn%Mod;
		}
	}
	int gt(int l){
		int n=1;
		while(n<l)n<<=1;
		return n;
	}
}
const int N=255;
int n,mod;
ll f[N][N*N/2];
unsigned long long g[N*N],g_[N*N/2],a1[N*N],a2[N*N],dft[N][1<<15];
ll fac[N*N],inv[N*N],ifac[N*N];
void init_fac(){
	fac[0]=1;
	For(i,1,N*N-1) fac[i]=fac[i-1]*i%Mod;
	inv[1]=1;
	For(i,2,N*N-1) inv[i]=(mod-mod/i)*inv[mod%i]%Mod;
	ifac[0]=ifac[1]=1;
	For(i,2,N*N-1) ifac[i]=ifac[i-1]*inv[i]%Mod;
}
void findrt(){
	int t=mod-1;
	vector<int> vs;
	for(int i=2;i<=t&&i*i<=mod;i++){
		if(t%i==0){
			vs.push_back(i);
			while(t%i==0) t/=i;
		}
	}
	if(t!=1) vs.push_back(t);
	for(int i=2;i<=mod;i++){
		bool flag=true;
		for(int j:vs){
			if(power(i,(mod-1)/j)==1){
				flag=false;
				break;
			}
		}
		if(flag)return NTT::G=i,void();
	}
}
int main(){
	cin.tie(nullptr)->sync_with_stdio(false);
	cin>>n>>mod;
	Mod=FastMod(mod);
	NTT::P=mod;
	findrt();
	NTT::init(1<<15);
	const int m=1<<14;
	init_fac();
	f[0][0]=1;
	For(i,1,n){
		For(j,0,(i-1)/2){
			int cnt=(j+1)*(i-j)-1,l1=C2(j),l2=C2(i-1-j);
			if(min(l1,l2)>300){
				copy(range(dft[j]),a1);
				copy(range(dft[i-1-j]),a2);
				For(k,0,m-1){
					g[k]=a1[k]*a2[k]%Mod;
				}
				NTT::idft(g,m);
				int w=1+((i-1)%2||j<(i-1)/2);
				For(k,0,C2(j)+C2(i-1-j)){
					(f[i][k+cnt]+=g[k]*fac[C2(j+1)+C2(i-j)-k]*w)%=Mod;
				}
			}else{
				memset(g_,0,sizeof(g_));
				For(k,0,l1){
					a1[k]=f[j][k]*ifac[C2(j+1)-k]%Mod;
				}
				For(k,0,l2){
					a2[k]=f[i-1-j][k]*ifac[C2(i-j)-k]%Mod;
				}
				For(k1,0,l1){
					#pragma GCC unroll 16
					For(k2,0,l2){
						g_[k1+k2]+=a1[k1]*a2[k2];
					}
					if(k1==l1||!(k1&15)){
						#pragma GCC unroll 16
						For(k,0,l1+l2){
							g_[k]%=Mod;
						}
					}
				}
				int w=1+((i-1)%2||j<(i-1)/2);
				For(k,0,C2(j)+C2(i-1-j)){
					(f[i][k+cnt]+=g_[k]*fac[C2(j+1)+C2(i-j)-k]*w)%=Mod;
				}
			}
		}
		Dec(j,C2(i),0){
			f[i][j]=(f[i][j]*fac[j]+f[i][j+1])%Mod;
		}
		For(j,0,C2(i)){
			(f[i][j]*=ifac[j])%=Mod;
		}
		if(C2(i)>300){
			For(j,0,C2(i)){
				dft[i][j]=f[i][j]*ifac[C2(i+1)-j]%Mod;
			}
			NTT::dft(dft[i],m);
		}
	}
	For(i,1,n-1){
		ll ans=f[i][0],inv=2;
		For(j,1,i+1){
			(ans*=j)%=Mod;
		}
		For(j,1,i*(i+1)/2){
			(inv*=j)%=Mod;
		}
		cout<<ans*power(inv,mod-2)%Mod<<'\n';
	}
	return 0;
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 12748kb

input:

10 998244353

output:

1
1
532396989
328786831
443364983
567813846
34567523
466373946
474334062

result:

ok 9 numbers

Test #2:

score: -100
Wrong Answer
time: 6268ms
memory: 76364kb

input:

250 998244353

output:

1
1
532396989
328786831
443364983
567813846
34567523
466373946
474334062
289137877
768923227
177538883
440227465
101981224
874960215
35275208
664066979
334444870
46651494
799130693
122319095
913072242
44703442
965640306
52873544
461938281
263838691
777326453
356621754
560569747
812581766
46147702
12...

result:

wrong answer 207th numbers differ - expected: '888624150', found: '712504328'