QOJ.ac

QOJ

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
#185214#6736. Alice and Bobteam1041#AC ✓112ms159920kbC++201.3kb2023-09-21 19:09:432023-09-21 19:09:44

Judging History

你现在查看的是最新测评结果

  • [2023-09-21 19:09:44]
  • 评测
  • 测评结果:AC
  • 用时:112ms
  • 内存:159920kb
  • [2023-09-21 19:09:43]
  • 提交

answer

#include<bits/stdc++.h>
#define IOS ios::sync_with_stdio(0);cin.tie(0);
#define int long long
#define endl '\n'
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define pb push_back
#define db double
#define ll long long

using namespace std;
const int N = 1e7+7,mod = 998244353;

ll qmi(ll a, ll b, ll p)
{
	ll res = 1;
	while(b)
	{
		if(b & 1) res = (ll)res * a % p;
		a = (ll)a * a % p;
		b >>= 1;
	}
	return res;
}
// ll qmi(ll x, ll y, ll p)
// {
	// if(y < 0) x = -x, y = -y;
	// ll z = (long double)x / p * y;
	// ll res = (unsigned long long)x*y - (unsigned long long)z * p;
	// return (res + p) % p;
// }
int fa[N],infa[N];
void initcp(int n)
{
	fa[0] = infa[0] = 1;
	for(int i = 1; i<= n; i ++)
	{
		fa[i] = (ll)fa[i-1] * i % mod;
		//infa[i] = (ll)infa[i-1] * qmi(i,mod-2,mod)%mod;
	}
	infa[n] = qmi(fa[n],mod-2,mod);
	for(int i = n; i > 0; i --) infa[i-1] = infa[i] * i % mod;
}

int P(int a, int b)
{
	if(a < b) return 0;
	return (ll)fa[a] * infa[a-b] % mod;
}

void solve()
{
	int n;
	cin >> n;
	int ans = 0;
	for(int i = 1; i <= n; i ++)
	{
		ans = (ans + P(n-i,i-1)*fa[n-i]%mod )%mod;
	}
	cout << ans << endl;
}

signed main()
{
	//IOS
	int T = 1;
	initcp(1e7+2);
	//cin >> T;
	while(T--)
	{
		solve();
	}
	
	return 0;
}

详细

Test #1:

score: 100
Accepted
time: 85ms
memory: 159848kb

input:

1

output:

1

result:

ok 1 number(s): "1"

Test #2:

score: 0
Accepted
time: 59ms
memory: 159808kb

input:

2

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 99ms
memory: 159920kb

input:

10

output:

997920

result:

ok 1 number(s): "997920"

Test #4:

score: 0
Accepted
time: 75ms
memory: 159904kb

input:

100

output:

188898954

result:

ok 1 number(s): "188898954"

Test #5:

score: 0
Accepted
time: 79ms
memory: 159840kb

input:

4

output:

10

result:

ok 1 number(s): "10"

Test #6:

score: 0
Accepted
time: 90ms
memory: 159804kb

input:

8

output:

12336

result:

ok 1 number(s): "12336"

Test #7:

score: 0
Accepted
time: 66ms
memory: 159780kb

input:

16

output:

373118483

result:

ok 1 number(s): "373118483"

Test #8:

score: 0
Accepted
time: 87ms
memory: 159780kb

input:

32

output:

314585464

result:

ok 1 number(s): "314585464"

Test #9:

score: 0
Accepted
time: 82ms
memory: 159776kb

input:

64

output:

627827331

result:

ok 1 number(s): "627827331"

Test #10:

score: 0
Accepted
time: 82ms
memory: 159896kb

input:

128

output:

828497685

result:

ok 1 number(s): "828497685"

Test #11:

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

input:

256

output:

65697890

result:

ok 1 number(s): "65697890"

Test #12:

score: 0
Accepted
time: 77ms
memory: 159776kb

input:

512

output:

854187619

result:

ok 1 number(s): "854187619"

Test #13:

score: 0
Accepted
time: 96ms
memory: 159872kb

input:

1024

output:

513823539

result:

ok 1 number(s): "513823539"

Test #14:

score: 0
Accepted
time: 76ms
memory: 159804kb

input:

1361956

output:

617368199

result:

ok 1 number(s): "617368199"

Test #15:

score: 0
Accepted
time: 95ms
memory: 159844kb

input:

7579013

output:

827172636

result:

ok 1 number(s): "827172636"

Test #16:

score: 0
Accepted
time: 88ms
memory: 159840kb

input:

8145517

output:

710624331

result:

ok 1 number(s): "710624331"

Test #17:

score: 0
Accepted
time: 84ms
memory: 159868kb

input:

6140463

output:

707600568

result:

ok 1 number(s): "707600568"

Test #18:

score: 0
Accepted
time: 94ms
memory: 159908kb

input:

3515281

output:

698302413

result:

ok 1 number(s): "698302413"

Test #19:

score: 0
Accepted
time: 107ms
memory: 159776kb

input:

6969586

output:

69470392

result:

ok 1 number(s): "69470392"

Test #20:

score: 0
Accepted
time: 90ms
memory: 159868kb

input:

2888636

output:

433579983

result:

ok 1 number(s): "433579983"

Test #21:

score: 0
Accepted
time: 95ms
memory: 159840kb

input:

9999998

output:

758172780

result:

ok 1 number(s): "758172780"

Test #22:

score: 0
Accepted
time: 112ms
memory: 159864kb

input:

9999999

output:

605195495

result:

ok 1 number(s): "605195495"

Test #23:

score: 0
Accepted
time: 102ms
memory: 159840kb

input:

10000000

output:

866813682

result:

ok 1 number(s): "866813682"