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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#413426#6736. Alice and BobSSHL#AC ✓135ms159904kbC++141.1kb2024-05-17 15:16:522024-05-17 15:16:52

Judging History

你现在查看的是最新测评结果

  • [2024-05-17 15:16:52]
  • 评测
  • 测评结果:AC
  • 用时:135ms
  • 内存:159904kb
  • [2024-05-17 15:16:52]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
constexpr int N=1e5+1;
constexpr ll mod=998244353;
constexpr int maxn=1e7+10;
ll fac[maxn],inv[maxn];
ll pow(ll a,ll b)
{
    ll res=1;
    a%=mod;
    while(b)
    {
        if(b&1)
        res=res*a%mod;
        a=a*a%mod;
        b>>=1;
    }
    return res;
}
void pre()
{
    fac[0]=1;
    for(int i=1;i<maxn;i++)
    {
        fac[i]=fac[i-1]*i%mod;

    }
    inv[maxn-1]=pow(fac[maxn-1],mod-2);
    for(int i=maxn-2;i>=0;i--)
    {
        inv[i]=inv[i+1]*(i+1)%mod;
    }
}
ll c(ll a,ll b)
{
    if(b>a||b<0)
    return 0;
    return fac[a]*inv[b]%mod*inv[a-b]%mod;
}
void solve()
{
    pre();
    ll n;
    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<<c(n-i,i-1)<<' '<<fac[n-i]<<'\n';
    }
    cout<<ans%mod;
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    // cin >> t;
    while (t--)
        solve();
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 90ms
memory: 159904kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 83ms
memory: 159900kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 82ms
memory: 159832kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 85ms
memory: 159844kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 82ms
memory: 159788kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 86ms
memory: 159780kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 78ms
memory: 159772kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 85ms
memory: 159844kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 85ms
memory: 159780kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 85ms
memory: 159788kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 82ms
memory: 159784kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 81ms
memory: 159772kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 85ms
memory: 159900kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 100ms
memory: 159900kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 127ms
memory: 159784kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 134ms
memory: 159856kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 115ms
memory: 159896kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 98ms
memory: 159784kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 127ms
memory: 159784kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 92ms
memory: 159840kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 128ms
memory: 159852kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 128ms
memory: 159860kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 135ms
memory: 159848kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"