QOJ.ac

QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#408992#6736. Alice and BobPhon#AC ✓592ms81860kbC++23942b2024-05-11 14:32:142024-05-11 14:32:15

Judging History

你现在查看的是最新测评结果

  • [2024-05-11 14:32:15]
  • 评测
  • 测评结果:AC
  • 用时:592ms
  • 内存:81860kb
  • [2024-05-11 14:32:14]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define debug(x) cerr<<#x<<": "<<x<<'\n';
#define int long long
typedef pair<int,int> PII;
const int N = 1e7 + 10, mod = 998244353;
int n, m, k, q, x;
double a, b, s, ops = 1e-4, cnt = 0, t = 0.5;
vector<int> v;
int fac[N];

int Pow (int a, int k) {
    int ans = 1ll % mod;
    for (; k; k >>= 1, a = a * a % mod)
        if (k & 1) ans = ans * a % mod;
    return ans;
}

int inv(int x){
    return Pow(x,mod - 2);
}

void unit(int m)
{
    fac[0] = 1;
    for(int i = 1;i <= m;i++)
        fac[i] = (fac[i - 1] * i) % mod;
}
void solve(){
	cin >> n;
	int ans = 0;
	for(int i = 1;2 * i - 1 <= n;i++)
		ans = (ans + Pow(fac[n - i], 2) * inv(fac[n - 2 * i + 1]) % mod) % mod;
	
	cout << ans;
}

signed main(){
	ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
	unit(1e7);
//	cout.flush();
//	int T;  cin >> T;
//	while(T--) 
		solve();
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 41ms
memory: 81804kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 40ms
memory: 81668kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 38ms
memory: 81848kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 38ms
memory: 81860kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 41ms
memory: 81792kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 41ms
memory: 81792kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 38ms
memory: 81812kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 45ms
memory: 81788kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 45ms
memory: 81788kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 45ms
memory: 81732kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 38ms
memory: 81860kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 34ms
memory: 81808kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 49ms
memory: 81724kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 116ms
memory: 81848kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 462ms
memory: 81732kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 489ms
memory: 81848kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 368ms
memory: 81792kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 239ms
memory: 81860kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 425ms
memory: 81728kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 197ms
memory: 81784kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 591ms
memory: 81732kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 592ms
memory: 81812kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 587ms
memory: 81708kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"