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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
#412554#6736. Alice and BobSunlight9#AC ✓211ms159872kbC++20774b2024-05-16 16:04:262024-05-16 16:04:26

Judging History

你现在查看的是最新测评结果

  • [2024-05-16 16:04:26]
  • 评测
  • 测评结果:AC
  • 用时:211ms
  • 内存:159872kb
  • [2024-05-16 16:04:26]
  • 提交

answer

#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int MAXN=1e7+7;
ll mod=998244353LL;
ll sum[MAXN],inv[MAXN];
int n;
inline ll ksm(ll x,ll y)
{
    ll res=1LL;
    while(y)
    {
        if(y&1LL) res=(res*x)%mod;
        x=(x*x)%mod;y=y>>1LL;
    }
    return res;
}
inline ll A(int x,int y)
{
    if(y>x) return 0;
    ll res=sum[x]*inv[x-y];
    return res%mod;
}
int main()
{
    cin>>n;
    sum[0]=1LL;
    for(int i=1;i<=n;i++) sum[i]=(sum[i-1]*(ll) i)%mod;
    inv[n]=ksm(sum[n],mod-2LL);
    for(int i=n-1;i>=1;i--) inv[i]=(inv[i+1]*(ll) (i+1LL))%mod;
    inv[0]=1LL;
    ll ans=0LL;
    for(int i=1;i<=n;i++)
    {
        ans+=A(n-i,i-1)*sum[n-i];
        ans%=mod;
    }
    cout<<ans;
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 5732kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5668kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 5644kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 1ms
memory: 5536kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 1ms
memory: 5732kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 1ms
memory: 5576kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 1ms
memory: 5724kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 1ms
memory: 5572kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 1ms
memory: 5576kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 1ms
memory: 5664kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 1ms
memory: 5576kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 5596kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 1ms
memory: 5732kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 21ms
memory: 27116kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 147ms
memory: 122600kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 124ms
memory: 133864kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 103ms
memory: 101420kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 71ms
memory: 60176kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 140ms
memory: 113752kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 62ms
memory: 52156kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 211ms
memory: 159840kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 210ms
memory: 159776kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 206ms
memory: 159872kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"