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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#409682#6736. Alice and Bobzouyua#AC ✓124ms159900kbC++231.1kb2024-05-12 15:26:572024-05-12 15:26:58

Judging History

你现在查看的是最新测评结果

  • [2024-05-12 15:26:58]
  • 评测
  • 测评结果:AC
  • 用时:124ms
  • 内存:159900kb
  • [2024-05-12 15:26:57]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int mod = 998244353;
const int N = 10000010;
typedef long long ll;
typedef pair<int, int> PII;

	ll fac[N], inv[N];
	
	ll fastpow(ll a, ll n){
		ll base = a, res = 1;
		while(n){
			if(n & 1) res = (res * base) % mod;
			base = (base * base) % mod;
			n >>= 1;
		}
		return res;
	}
	
	ll Inv(ll a){
		return fastpow(a, mod - 2);
	}

	ll C(ll n, ll m){
		if(n < 0 || m < 0 || n < m) return 0;
		return fac[n] * inv[m] % mod * inv[n - m] % mod;
	}
	
	void init(ll n){
		fac[0] = 1;
		for(int i = 1; i <= n; i ++) fac[i] = (i * fac[i - 1]) % mod;
		inv[n] = Inv(fac[n]);
		for(int i = n - 1; i >= 0; i --) inv[i] = inv[i + 1] * (i + 1) % mod;
	}
	
void solve(){
	int n ; cin >> n;
	int res = fac[n - 1];
	for(int i = n - 2; i >= n / 2 ;i --)
	{
		int t = 0;
		t= fac[i] * fac[n - i - 1];
		t %= mod;
		t *= C(i, n - i - 1);
		res += t;
		res %= mod;
	}
	cout << res % mod << endl;
}

signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	init(N - 10);
	int t = 1;
	while(t --){
		solve();
	}
	return 0;
} 

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 60ms
memory: 159856kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 76ms
memory: 159744kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 85ms
memory: 159844kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 68ms
memory: 159820kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 80ms
memory: 159792kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 92ms
memory: 159836kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 68ms
memory: 159828kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 93ms
memory: 159800kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 60ms
memory: 159840kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 88ms
memory: 159800kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

score: 0
Accepted
time: 88ms
memory: 159836kb

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 64ms
memory: 159836kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 39ms
memory: 159848kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 87ms
memory: 159752kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 112ms
memory: 159840kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 91ms
memory: 159756kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 97ms
memory: 159900kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 93ms
memory: 159820kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 104ms
memory: 159884kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 59ms
memory: 159752kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 106ms
memory: 159836kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 124ms
memory: 159880kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 80ms
memory: 159820kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"