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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
#411623#6678. Gem Island 2le0n#TL 311ms245760kbC++141.1kb2024-05-15 16:48:502024-05-15 16:48:50

Judging History

你现在查看的是最新测评结果

  • [2024-05-15 16:48:50]
  • 评测
  • 测评结果:TL
  • 用时:311ms
  • 内存:245760kb
  • [2024-05-15 16:48:50]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

const int mod = 998244353, N = 3e7 + 5;
int fac[N], inv[N], f[N], g[N];
int qpow(int x, int y)
{
	int ans = 1;
	while(y)
	{
		if(y & 1)
			ans = (ll)ans * x % mod;
		x = (ll)x * x % mod;
		y >>= 1;
	}
	return ans;
}
void prep(int n)
{
	int i;
	fac[0] = 1;
	for(i = 1; i <= n; i++)
		fac[i] = (ll)fac[i - 1] * i % mod;
	inv[n] = qpow(fac[n], mod - 2);
	for(i = n; i >= 1; i--)
		inv[i - 1] = (ll)inv[i] * i % mod;
}
int C(int x, int y)
{
	return (x < y || y < 0) ? 0 : ((ll)fac[x] * inv[y] % mod * inv[x - y] % mod);
}

int main()
{
	int n, d, r, i, j, ans = 0, tmp;
	prep(3e7);
	scanf("%d%d%d", &n, &d, &r);
	for(i = 1; i <= n; i++)
	{
		g[i] = ((ll)i * C(i - 2, r - 2) + mod - (ll)r * C(i - 1, r - 1) % mod) % mod;
		if((i + r - 1) & 1)
			g[i] = mod - g[i];
	}
	g[1] = 1;
	for(i = 1; i <= n; i++)
	{
		tmp = 0;
		for(j = 0; j <= d / i; j++)
			tmp = (tmp + C(d - i * j + n - 1, n - 1)) % mod;
		ans = (ans + (ll)C(n, i) * tmp % mod * g[i]) % mod;
	}
	ans = (ll)ans * qpow(C(d + n - 1, n - 1), mod - 2) % mod;
	printf("%d\n", ans);
	return 0;
}

详细

Test #1:

score: 100
Accepted
time: 245ms
memory: 238040kb

input:

2 3 1

output:

499122180

result:

ok 1 number(s): "499122180"

Test #2:

score: 0
Accepted
time: 284ms
memory: 238164kb

input:

3 3 2

output:

698771052

result:

ok 1 number(s): "698771052"

Test #3:

score: 0
Accepted
time: 277ms
memory: 238140kb

input:

5 10 3

output:

176512750

result:

ok 1 number(s): "176512750"

Test #4:

score: 0
Accepted
time: 282ms
memory: 238164kb

input:

5 4 3

output:

71303175

result:

ok 1 number(s): "71303175"

Test #5:

score: 0
Accepted
time: 245ms
memory: 238212kb

input:

37 47 12

output:

962577218

result:

ok 1 number(s): "962577218"

Test #6:

score: 0
Accepted
time: 266ms
memory: 238204kb

input:

29 50 26

output:

175627840

result:

ok 1 number(s): "175627840"

Test #7:

score: 0
Accepted
time: 267ms
memory: 238208kb

input:

298 498 221

output:

765832019

result:

ok 1 number(s): "765832019"

Test #8:

score: 0
Accepted
time: 259ms
memory: 238136kb

input:

497 456 243

output:

414028615

result:

ok 1 number(s): "414028615"

Test #9:

score: 0
Accepted
time: 276ms
memory: 238576kb

input:

114514 1926 817

output:

691374994

result:

ok 1 number(s): "691374994"

Test #10:

score: 0
Accepted
time: 282ms
memory: 245760kb

input:

1919810 1554 1999

output:

3553

result:

ok 1 number(s): "3553"

Test #11:

score: 0
Accepted
time: 311ms
memory: 245664kb

input:

1926817 1514 1001

output:

685086550

result:

ok 1 number(s): "685086550"

Test #12:

score: 0
Accepted
time: 266ms
memory: 243804kb

input:

1432132 1425 1425

output:

2850

result:

ok 1 number(s): "2850"

Test #13:

score: -100
Time Limit Exceeded

input:

14999999 15000000 14999999

output:


result: