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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#368703#6736. Alice and BobliutaowoainiAC ✓170ms238028kbC++171.1kb2024-03-27 15:32:222024-03-27 15:32:23

Judging History

This is the latest submission verdict.

  • [2024-03-27 15:32:23]
  • Judged
  • Verdict: AC
  • Time: 170ms
  • Memory: 238028kb
  • [2024-03-27 15:32:22]
  • Submitted

answer

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1e7 + 10, mod = 998244353;
int fact[N], infact[N], xiaoyu[N];
int qmi(int a, int b, int p)
{
    int res = 1;
    while (b)
    {
        if (b & 1) res = res * a % p;
        a = a * a % p;
        b >>= 1;
    }
    return res;
}
int c(int a, int b)
{
    return fact[a] * infact[b] % mod * infact[a - b] % mod;
}
signed main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int ans = 0;
    int n;
    cin >> n;
    fact[0] = infact[0] = 1;
    for (int i = 1; i <=n; i++)
    {
        fact[i] = fact[i - 1] * i % mod;
    }
    infact[n] = qmi(fact[n], mod - 2, mod);
    for (int i = n - 1; i >= 0; i--)
    {
        infact[i] = infact[i + 1] * (i + 1) % mod;
    }
    xiaoyu[0] = 1;
    for (int i = 1; i <= n; i++) xiaoyu[i] = (xiaoyu[i - 1] * i) % mod;
    for (int i = 1; i <= (n + 1) / 2; i++)
    {
        ans = (ans + c(n - i, i - 1) * xiaoyu[n - i] % mod * xiaoyu[i - 1] % mod) % mod;
    }
    cout << ans << endl;
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 7712kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 7716kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 7708kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 1ms
memory: 7696kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 1ms
memory: 7700kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 1ms
memory: 7752kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 7660kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 1ms
memory: 7796kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 1ms
memory: 7668kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 1ms
memory: 7656kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 1ms
memory: 7764kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 7780kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 1ms
memory: 7772kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 21ms
memory: 39700kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 100ms
memory: 184592kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 114ms
memory: 196440kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 95ms
memory: 149952kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 63ms
memory: 92604kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 112ms
memory: 169080kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 27ms
memory: 75416kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 149ms
memory: 238020kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 139ms
memory: 238028kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 170ms
memory: 238024kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"