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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#413228#6736. Alice and BobalbionAC ✓136ms160132kbC++17736b2024-05-17 10:12:542024-05-17 10:12:55

Judging History

你现在查看的是最新测评结果

  • [2024-05-17 10:12:55]
  • 评测
  • 测评结果:AC
  • 用时:136ms
  • 内存:160132kb
  • [2024-05-17 10:12:54]
  • 提交

answer

#include<bits/stdc++.h>
#define MO 998244353
using namespace std;
int i,n;
long long ans;
long long jc[10000005][2];
long long qsm(long long x,long long y)
{
  long long res=1;
  while (y)
    {
      if (y&1) res=(res*x)%MO;
      y>>=1;x=(x*x)%MO;
	}
  return res;
}
long long ny(long long x)
{
  return qsm(x,MO-2);
}
long long c(int n,int m)
{
  return jc[n][0]*jc[n-m][1]%MO*jc[m][1]%MO; 
}
int main()
{
  scanf("%d",&n);jc[0][0]=1;
  for (i=1;i<=n;++i) jc[i][0]=(jc[i-1][0]*i)%MO;
  jc[n][1]=ny(jc[n][0]);
  for (i=n-1;i>=0;--i) jc[i][1]=jc[i+1][1]*(i+1)%MO;
  ans=0;
  for (i=1;i<=(n+1)/2;++i) 
    ans=(ans+c(n-i,i-1)%MO*jc[n-i][0]%MO*jc[i-1][0]%MO)%MO;
  printf("%lld",ans);
  return 0;
}


Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 3864kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3792kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

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

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3864kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3948kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3864kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 3872kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

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

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3800kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3812kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3692kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 3956kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3832kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 14ms
memory: 26080kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 85ms
memory: 123876kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 93ms
memory: 133180kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 64ms
memory: 101756kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 39ms
memory: 60448kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 81ms
memory: 112920kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 29ms
memory: 49868kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 126ms
memory: 160132kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 136ms
memory: 160064kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 131ms
memory: 160132kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"