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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#394190#6736. Alice and BobTrappedGhost#AC ✓635ms81528kbC++141.1kb2024-04-20 09:57:262024-04-20 09:57:26

Judging History

你现在查看的是最新测评结果

  • [2024-04-20 09:57:26]
  • 评测
  • 测评结果:AC
  • 用时:635ms
  • 内存:81528kb
  • [2024-04-20 09:57:26]
  • 提交

answer

#include<iostream>
#define ll long long
#include<algorithm>
#include<vector>
#include<iomanip>
#include<map>

const double eps = 1e-4;
const ll mod = 998244353;

ll exgcd(ll a, ll b, ll& x, ll& y) 
{ 
    if (b == 0) return x = 1, y = 0, a; 
    ll r = exgcd(b, a % b, x, y); 
    std::tie(x, y) = std::make_tuple(y, x - (a/b)*y); 
    return r; 
}

ll niyuan(ll n,ll mod)
{
    ll x,y;
    ll r=exgcd(n,mod,x,y);
    x=(x%mod+mod)%mod;
    return x;
}

void solve()
{
    ll n;
    std::cin>>n;
    ll x=1;
    ll ans=0;
    std::vector<ll> v(n+1);
    v[0]=1;
    for(int i=1;i<=n;i++)
    {
        x*=i;
        x%=mod;
        v[i]=x;
    }
    for(int i=1;i<=(n+1)/2;i++)
    {
        ll a =((v[n-i]*niyuan(v[n-i - (i-1)],mod))%mod) * v[n-(i)]%mod;
        //std::cout<<n-i<<" "<<n-i - (i-1)<<" "<<n-(i-1)<<"\n";
        ans+=a;
        ans%=mod;
    }
    std::cout<<ans<<"\n";

}

int main(){
    std::ios::sync_with_stdio(0);
    std::cin.tie(0);
    std::cout.tie(0);
    ll test=1;
    //std::cin>>test;
    while(test--){
        solve();
    }
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3680kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3648kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3528kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3580kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3804kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3868kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 3580kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3640kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3876kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3648kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3676kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 0ms
memory: 3592kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3584kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 88ms
memory: 13944kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 481ms
memory: 62556kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 512ms
memory: 66776kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 388ms
memory: 51156kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 219ms
memory: 30488kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 437ms
memory: 57524kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 182ms
memory: 25808kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 635ms
memory: 81528kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 630ms
memory: 81404kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 631ms
memory: 81360kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"