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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#209874#6736. Alice and BobhuamuyichunAC ✓101ms161776kbC++141.1kb2023-10-10 18:39:352023-10-10 18:39:36

Judging History

你现在查看的是最新测评结果

  • [2023-10-10 18:39:36]
  • 评测
  • 测评结果:AC
  • 用时:101ms
  • 内存:161776kb
  • [2023-10-10 18:39:35]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1e7 + 10;
const int mod = 998244353;
int n, m, k;
string s1, s2;
int h[N], idx, ne[N];
vector<int> pa;
double a, b;
int infact[N];
int fact[N];

int qmi(int a, int k, int p) {
	int res = 1;
	while (k) {
		if (k & 1) res = res * a % p;
		a = a * a % p;
		k >>= 1;
	}
	return res;
}


void solve() {
	cin >> n;
	fact[0] = infact[0] = 1;
	for (int i = 1; i < n; i++) {
		fact[i] = fact[i - 1] * i % mod;
//		infact[i] = infact[i - 1] * qmi(i, mod - 2, mod) % mod;
	}
	infact[n-1]=qmi(fact[n-1],mod-2,mod);
	for(int i=n-2;i>=1;i--)
	{
		infact[i]=infact[i+1]*(i+1)%mod;
	}
	int ans = 0;
	for (int i = 1; i <= n + 1; i++) {

		if (n - i >= i - 1) {
			int t1 = fact[n - i] % mod;
			int t2 = fact[n - i] * infact[n + 1 - 2 * i] % mod;
			ans = (ans + (t1 * t2) % mod) % mod;
		}

	}
	//cout<<fact[3]<<endl;
	cout << ans << endl;
}


signed main() {
	int t = 1;
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	//cin >> t;
	while (t--) {
		solve();
	}
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 7492kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

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

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 7664kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 0ms
memory: 7540kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 1ms
memory: 7476kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 1ms
memory: 7532kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

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

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

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

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

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

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 0ms
memory: 7532kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 0ms
memory: 7532kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 1ms
memory: 7536kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 0ms
memory: 7536kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 19ms
memory: 29832kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 73ms
memory: 126128kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 97ms
memory: 136092kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 59ms
memory: 104856kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 42ms
memory: 65252kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 82ms
memory: 118996kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 38ms
memory: 53880kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 100ms
memory: 161480kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 101ms
memory: 160116kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 99ms
memory: 161776kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"