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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#183282#6736. Alice and Bobucup-team004#AC ✓104ms81332kbC++20898b2023-09-19 12:53:152023-09-19 12:53:15

Judging History

你现在查看的是最新测评结果

  • [2023-09-19 12:53:15]
  • 评测
  • 测评结果:AC
  • 用时:104ms
  • 内存:81332kb
  • [2023-09-19 12:53:15]
  • 提交

answer

#include <bits/stdc++.h>

using i64 = long long;

constexpr int P = 998244353;

int power(int a, int b) {
    int res = 1;
    for (; b; b /= 2, a = 1LL * a * a % P) {
        if (b % 2) {
            res = 1LL * res * a % P;
        }
    }
    return res;
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    int n;
    std::cin >> n;
    
    std::vector<int> fac(n + 1), invfac(n + 1);
    fac[0] = 1;
    for (int i = 1; i <= n; i++) {
        fac[i] = 1LL * fac[i - 1] * i % P;
    }
    invfac[n] = power(fac[n], P - 2);
    for (int i = n; i; i--) {
        invfac[i - 1] = 1LL * invfac[i] * i % P;
    }
    
    int ans = 0;
    for (int i = 1; n - i >= i - 1; i++) {
        ans = (ans + 1LL * fac[n - i] * invfac[n - i - (i - 1)] % P * fac[n - i]) % P;
    }
    std::cout << ans << "\n";
    
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3500kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3780kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3544kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3564kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3612kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3568kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 0ms
memory: 3592kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3544kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3596kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3612kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 3652kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 0ms
memory: 3804kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3628kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 12ms
memory: 13944kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 76ms
memory: 62704kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 87ms
memory: 66944kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 63ms
memory: 51228kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 37ms
memory: 30700kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 66ms
memory: 57732kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 30ms
memory: 25768kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 100ms
memory: 81264kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 100ms
memory: 81268kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 104ms
memory: 81332kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"