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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#16078#5. 在线 O(1) 逆元Prean100 ✓3941ms23632kbC++1.0kb2021-11-17 18:31:002024-11-05 21:46:17

Judging History

你现在查看的是最新测评结果

  • [2024-11-05 21:46:17]
  • 管理员手动重测本题所有提交记录
  • 测评结果:100
  • 用时:3941ms
  • 内存:23632kb
  • [2024-11-05 21:42:50]
  • 管理员手动重测本题所有提交记录
  • 测评结果:80
  • 用时:4645ms
  • 内存:23504kb
  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2022-05-03 22:51:31]
  • 评测
  • 测评结果:70
  • 用时:1433ms
  • 内存:22972kb
  • [2021-11-17 18:31:00]
  • 提交

answer

#include "inv.h"
typedef unsigned ui;
typedef unsigned long long ull;
const ui mod=998244353,M1=1000,M2=M1*M1;
const double invM1=1./M1+1e-15,INV=1.*M2/mod+1e-15;
ui T,len,fra[M2+5],Inv[M2+5],sum[M2+5];
ui q[M2+5];ull p[M2+5];
inline ull abs(const ull&a){
	return a>>63?-a:a;
}
inline void Init(){
	ui i,j,x;
	for(i=1;i^M1;++i){
		const double&INV=1./i+1e-15;
		for(j=0;j^i;++j)if(!sum[x=1ull*j*M2*INV])sum[x]=1,fra[x]=M1*i+j;
	}
	for(i=0;i<=M2;++i){
		if(sum[i])++len,q[len]=fra[i]*invM1,p[len]=1ull*(fra[i]-q[len]*M1)*mod;
		if(i)sum[i]+=sum[i-1];Inv[i]=i>1?1ull*(mod-mod/i)*Inv[mod%i]%mod:i;
	}
}
inline ui Qry(const ui&a){
	static ui q,k;static ull t;
	if(a<=M2)return Inv[a];if(mod-a<=M2)return mod-Inv[mod-a];k=sum[ui(a*INV)];
	if(k<=len){
		q=::q[k];t=1ull*a*q-p[k];
		if(abs(t)<=M2)return 1ull*q*(t>>63?mod-Inv[-t]:Inv[t])%mod;
	}
	if(++k<=len){
		q=::q[k];t=1ull*a*q-p[k];
		if(abs(t)<=M2)return 1ull*q*(t>>63?mod-Inv[-t]:Inv[t])%mod;
	}
	return-1;
}
void init(int p){
	Init();
}
int inv(int x){
	return Qry(x);
}

Details


Pretests


Final Tests

Test #1:

score: 10
Accepted
time: 18ms
memory: 22364kb

Test #2:

score: 20
Accepted
time: 382ms
memory: 21160kb

Test #3:

score: 30
Accepted
time: 1858ms
memory: 22328kb

Test #4:

score: 20
Accepted
time: 3040ms
memory: 21332kb

Test #5:

score: 20
Accepted
time: 3941ms
memory: 23632kb