QOJ.ac

QOJ

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
#840212#5. 在线 O(1) 逆元Graygoo30 1476ms81824kbC++14693b2025-01-02 16:20:252025-01-02 16:20:26

Judging History

你现在查看的是最新测评结果

  • [2025-01-02 16:20:26]
  • 评测
  • 测评结果:30
  • 用时:1476ms
  • 内存:81824kb
  • [2025-01-02 16:20:25]
  • 提交

answer

#include<bits/stdc++.h>
//#include"inv.h"
using namespace std;
#define ll long long
const ll mod = 998244353;
const ll magic = 68996401;
int prime[]={2,3,5,7,11};
ll iv[10000005];
ll qpow(ll a,int w){
    ll ans=1;
    while(w){
        if(w&1)ans=ans*a%mod;
        w>>=1;a=a*a%mod;
    }
    return ans;
}
void init(int p){
    iv[1]=1;
    for(int i=2;i<=10000000;i++)iv[i]=(mod-iv[mod%i]*(mod/i)%mod)%mod;
    return ;
}
int inv(int x){
    ll ans=magic;x=x*magic%mod;
    for(int i=0;i<5;i++){
        while(x%prime[i]==0)ans=ans*iv[prime[i]]%mod,x/=prime[i];
    }
    if(x<=10000000)ans=ans*iv[x]%mod;
    else ans=ans*qpow(x,mod-2)%mod;
    return ans;
}

详细


Pretests


Final Tests

Test #1:

score: 10
Accepted
time: 113ms
memory: 81816kb

Test #2:

score: 20
Accepted
time: 1476ms
memory: 81824kb

Test #3:

score: 0
Time Limit Exceeded

Test #4:

score: 0
Time Limit Exceeded

Test #5:

score: 0
Time Limit Exceeded