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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#183574#6736. Alice and Bobxz1195160770#AC ✓199ms238048kbC++201012b2023-09-19 17:45:432023-09-19 17:45:43

Judging History

你现在查看的是最新测评结果

  • [2023-09-19 17:45:43]
  • 评测
  • 测评结果:AC
  • 用时:199ms
  • 内存:238048kb
  • [2023-09-19 17:45:43]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
using i64=long long;
using ll=long long;
const int N=1e7+10,mod=998244353;
int n;
ll fac[N],infac[N],inv[N];
ll qpow(ll a,ll b,ll p){
    ll res=1;
    while(b){
        if(b&1) res=res*a%mod;
        a=a*a%mod;
        b>>=1;
    }
    return res;
}
void init(int n=N-1){
    fac[0]=1;
    for(int i=1;i<=n;i++) fac[i]=fac[i-1]*i%mod;
    infac[n-1]=qpow(fac[n-1],mod-2,mod);
    for(int i=n-2;i>=0;i--)
        infac[i]=infac[i+1]*(i+1)%mod;
    inv[0]=inv[1]=1;
    for(int i=2;i<=n;i++) inv[i]=(mod-mod/i*inv[mod%i]%mod)%mod;
}
ll C(ll a,ll b){
    if(a<b) return 0;
    return fac[a]*infac[b]%mod*infac[a-b]%mod;
}
void solve(){
    cin>>n;
    ll ans=0;
    for(int i=1;i<=n;i++){
        ans+=C(n-i,i-1)*fac[n-i]%mod*fac[i-1]%mod;
        ans%=mod;
    }
    cout<<ans<<endl;
}
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0),cout.tie(0);
    int t=1;
    init();
    //cin>>t;
    while(t--) solve();
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 131ms
memory: 238020kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 182ms
memory: 238048kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 179ms
memory: 237960kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 178ms
memory: 237960kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 125ms
memory: 238024kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 155ms
memory: 238012kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 185ms
memory: 237956kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 178ms
memory: 237960kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 148ms
memory: 238016kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 178ms
memory: 238028kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 179ms
memory: 238028kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 148ms
memory: 238020kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 104ms
memory: 237948kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 146ms
memory: 238020kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 180ms
memory: 237952kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 197ms
memory: 237992kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 199ms
memory: 238024kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 146ms
memory: 237996kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 164ms
memory: 238016kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 157ms
memory: 238024kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 185ms
memory: 238032kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 180ms
memory: 238024kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 136ms
memory: 237980kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"