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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
#383582#6736. Alice and Bobyouxiao#AC ✓115ms165488kbC++201.0kb2024-04-09 15:37:132024-04-09 15:37:14

Judging History

你现在查看的是最新测评结果

  • [2024-04-09 15:37:14]
  • 评测
  • 测评结果:AC
  • 用时:115ms
  • 内存:165488kb
  • [2024-04-09 15:37:13]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N=11000000;
const double eps=1e-5;
const int mod=998244353;
#define endl '\n'

ll ksm(ll a,ll b,ll p=mod){
    ll res=1;
    for(;b;b>>=1,a=a*a%p){
        if(b&1)res=a*res%p;
    }
    return res;
}

ll fac[N],infac[N];
void init(){
    fac[0]=fac[1]=1;
    for(int i=2;i<=10000000;i++)fac[i]=fac[i-1]*i%mod;
    infac[10000000]=ksm(fac[10000000],mod-2);
    for(int i=10000000;i>=1;i--)infac[i-1]=infac[i]*i%mod;
}
int main(){
    #ifdef LOCAL
    freopen("input.in","r",stdin);
    freopen("output.out","w",stdout);
    #endif
    ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
    int n;
    init();
    cin>>n;
    ll ans=0;
    for(int i=1;i<=n;i++){
        if(n-i<i-1){
            // ans=ans+fac[n-1];
            // if(ans>=mod)ans%=mod;
        }
        else{
            ans=ans+((fac[n-i]*fac[n-1-(i-1)]%mod*infac[n-i-(i-1)])%mod+mod);
            if(ans>=mod)ans%=mod;
        }
    }
    cout<<ans<<endl;

}

详细

Test #1:

score: 100
Accepted
time: 79ms
memory: 162904kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 49ms
memory: 161960kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 83ms
memory: 165408kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 99ms
memory: 162344kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 98ms
memory: 163612kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 55ms
memory: 162392kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 59ms
memory: 163660kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 74ms
memory: 161624kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 94ms
memory: 162848kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 83ms
memory: 161920kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 82ms
memory: 161692kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 67ms
memory: 162152kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 69ms
memory: 162856kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 70ms
memory: 162056kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 79ms
memory: 161856kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 61ms
memory: 165488kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 107ms
memory: 165332kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 110ms
memory: 163016kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 105ms
memory: 162552kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 92ms
memory: 162880kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 115ms
memory: 161972kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 111ms
memory: 162464kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 63ms
memory: 162276kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"