QOJ.ac

QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#398994#6736. Alice and BobszjAC ✓655ms81808kbC++111.0kb2024-04-25 20:43:432024-04-25 20:43:43

Judging History

你现在查看的是最新测评结果

  • [2024-04-25 20:43:43]
  • 评测
  • 测评结果:AC
  • 用时:655ms
  • 内存:81808kb
  • [2024-04-25 20:43:43]
  • 提交

answer

#include<bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
#define IOS std::ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
const long double PI = acos(-1);
const ll mod = 998244353;
const int maxn = 1e7 + 7;
const int P = 13331;

ll qgcd(ll a, ll b) {
    return b == 0 ? a : qgcd(b, a % b);
}

ll qpow(ll a, ll b) {
    ll ans = 1;
    while (b) {
        if (b & 1)
            ans = ans * a % mod;
        a = a * a % mod;
        b >>= 1;
    }
    return ans % mod;
}

ll n;
ll d[maxn];

void solve() {
	cin >> n;
	if (n == 1 || n == 2) {
		cout << 1;
		return;
	}
	d[0] = 1;
	for (ll i = 1; i <= n; i++) {
		d[i] = d[i - 1] * i % mod;
	}
	ll ans = 0;
	for (int i = 1; i <= (n + 1) / 2; i++) {
		ans = (ans + d[n - i] * qpow(d[i - 1] * d[(n - 2 * i + 1)] % mod, mod - 2) % mod * d[n - i] % mod * d[i - 1] % mod) % mod;
	}
	cout << ans;
}

int main() {
    IOS;
    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: 0ms
memory: 3624kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3528kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3616kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3576kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 0ms
memory: 3700kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 0ms
memory: 3644kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

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

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 0ms
memory: 3636kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 0ms
memory: 3572kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 3680kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

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

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 0ms
memory: 3552kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 3688kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 90ms
memory: 15832kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 489ms
memory: 63512kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 531ms
memory: 68404kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 392ms
memory: 52052kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 227ms
memory: 31968kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 446ms
memory: 58856kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 182ms
memory: 27240kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 632ms
memory: 81732kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 642ms
memory: 81756kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 655ms
memory: 81808kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"