QOJ.ac

QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#444616#8526. Polygon IIucup-team3510#AC ✓1346ms12768kbC++202.2kb2024-06-15 20:23:592024-06-15 20:23:59

Judging History

你现在查看的是最新测评结果

  • [2024-06-15 20:23:59]
  • 评测
  • 测评结果:AC
  • 用时:1346ms
  • 内存:12768kb
  • [2024-06-15 20:23:59]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

const int B = 1100, mod = 1e9 + 7;
int dp[55][2205][2], f[4205][2], pw[1005], fac[1005], inv[1005];
int ww[1005][1005];
int cnt[55], C[1005][1005];
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;
}
int F(int x, int y) // x [0,1) <= y
{
	int i, ans = 0, tmp;
	if(y > x)
		return 1;
	for(i = 0; i <= y; i++)
	{
		tmp = (ll)C[x][i] * ww[y - i][x] % mod * inv[x] % mod;
		if(i & 1)
			ans = (ans + mod - tmp) % mod;
		else
			ans = (ans + tmp) % mod;
	}
	return ans;
}

int main()
{
	int n, i, j, k, c, a, ans = 0, tot = 0;
	scanf("%d", &n);
	for(i = 1; i <= n; i++)
	{
		scanf("%d", &a);
		for(j = 0; j <= a; j++)
			cnt[j]++;
		tot += a;
	}
	for(i = 0; i <= n; i++)
	{
		C[i][0] = 1;
		for(j = 1; j <= i; j++)
			C[i][j] = (C[i - 1][j] + C[i - 1][j - 1]) % mod;
	}
	pw[0] = 1;
	for(i = 1; i <= n; i++)
		pw[i] = pw[i - 1] * ((mod + 1ll) / 2) % mod;
	fac[0] = 1;
	for(i = 1; i <= n; i++)
		fac[i] = (ll)fac[i - 1] * i % mod;
	for(i = 0; i <= n; i++)
		inv[i] = qpow(fac[i], mod - 2); 
	for(i = 0; i <= n; i++)
	{
		ww[i][0] = 1;
		for(j = 1; j <= n; j++)
			ww[i][j] = (ll)ww[i][j - 1] * i % mod;
	}
	dp[51][B][0] = 1;
	for(i = 50; i >= 1; i--)
	{
		for(j = -2 * B; j <= 2 * B; j += 2)
		{
			for(k = 0; k <= cnt[i]; k++)
			{
				c = max(min(j + k + B, 2 * B), 0);
				dp[i][c][0] = (dp[i][c][0] + (ll)dp[i + 1][j / 2 + B][0] * C[cnt[i]][k]) % mod;
			}
			for(k = 0; k < cnt[i]; k++)
			{
				c = max(min(j + k + B, 2 * B), 0);
				dp[i][c][1] = (dp[i][c][1] + ((ll)dp[i + 1][j / 2 + B][0] * (cnt[i] - cnt[i + 1]) + dp[i + 1][j / 2 + B][1]) % mod * C[cnt[i] - 1][k] % mod) % mod;
				c = max(min(j + k - 1 + B, 2 * B), 0);
				dp[i][c][1] = (dp[i][c][1] + ((ll)dp[i + 1][j / 2 + B][0] * (cnt[i] - cnt[i + 1]) + dp[i + 1][j / 2 + B][1]) % mod * C[cnt[i] - 1][k] % mod) % mod;
			}
		}
	}
	for(j = -B; j <= B; j++)
		ans = (ans + (ll)F(n, 1 - j) * (dp[1][j + B][1] + (ll)(cnt[0] - cnt[1]) * dp[1][j + B][0] % mod)) % mod;
	ans = (ll)ans * qpow(2, mod - 1 - tot) % mod;
	ans = (mod + 1 - ans) % mod;
	printf("%d\n", ans);
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 8380kb

input:

3
0 2 0

output:

166666668

result:

ok 1 number(s): "166666668"

Test #2:

score: 0
Accepted
time: 0ms
memory: 6764kb

input:

3
0 0 0

output:

500000004

result:

ok 1 number(s): "500000004"

Test #3:

score: 0
Accepted
time: 0ms
memory: 8888kb

input:

3
5 6 7

output:

208333335

result:

ok 1 number(s): "208333335"

Test #4:

score: 0
Accepted
time: 0ms
memory: 6836kb

input:

3
0 25 50

output:

889268532

result:

ok 1 number(s): "889268532"

Test #5:

score: 0
Accepted
time: 4ms
memory: 7924kb

input:

10
39 11 25 1 12 44 10 46 27 15

output:

913863330

result:

ok 1 number(s): "913863330"

Test #6:

score: 0
Accepted
time: 45ms
memory: 6964kb

input:

57
43 22 3 16 7 5 24 32 25 16 41 28 24 30 28 10 32 48 41 43 34 37 48 34 3 9 21 41 49 25 2 0 36 45 34 33 45 9 42 29 43 9 38 34 44 33 44 6 46 39 22 36 40 37 19 34 3

output:

400729664

result:

ok 1 number(s): "400729664"

Test #7:

score: 0
Accepted
time: 57ms
memory: 7228kb

input:

100
44 32 6 6 6 44 12 32 6 9 23 12 14 23 12 14 23 49 6 14 32 23 49 9 32 24 23 6 32 6 49 23 12 44 24 9 14 6 24 44 24 23 44 44 49 32 49 12 49 49 24 49 12 23 3 14 6 3 3 6 12 3 49 24 49 24 24 32 23 32 49 14 3 24 49 3 32 14 44 24 49 3 32 23 49 44 44 9 23 14 49 9 3 6 44 24 3 3 12 44

output:

32585394

result:

ok 1 number(s): "32585394"

Test #8:

score: 0
Accepted
time: 263ms
memory: 12652kb

input:

1000
2 27 0 0 27 0 2 0 27 0 27 27 0 0 0 0 0 2 0 27 0 2 2 0 27 27 0 0 0 27 2 2 2 27 0 2 27 2 0 2 27 0 0 27 0 27 0 0 27 2 27 2 2 27 2 27 0 0 27 0 27 0 2 27 2 2 0 27 27 27 27 0 27 0 27 0 2 2 0 2 2 27 0 0 27 0 0 27 0 2 27 27 2 27 2 0 0 2 27 27 27 27 27 27 2 2 0 2 2 0 2 2 0 27 0 27 2 2 0 27 27 0 0 27 2 2...

output:

94588769

result:

ok 1 number(s): "94588769"

Test #9:

score: 0
Accepted
time: 811ms
memory: 12708kb

input:

1000
40 14 47 3 32 18 3 49 22 23 32 18 23 24 18 32 23 39 32 27 49 49 22 50 50 22 23 47 14 47 50 32 22 24 49 49 18 22 18 22 50 3 32 47 40 3 39 22 24 47 32 49 49 22 32 39 14 49 39 3 32 22 24 18 39 49 24 18 40 23 23 49 39 39 18 39 27 49 14 27 27 14 18 24 39 22 40 50 18 18 18 39 39 18 23 23 22 3 49 47 2...

output:

626481946

result:

ok 1 number(s): "626481946"

Test #10:

score: 0
Accepted
time: 632ms
memory: 12636kb

input:

1000
28 32 35 9 21 11 43 23 45 15 23 2 8 3 39 41 31 9 45 35 27 14 40 28 31 9 31 9 9 40 8 6 27 43 3 27 23 49 27 6 28 25 11 9 15 27 38 27 12 28 25 2 15 27 45 6 27 1 21 38 1 25 27 21 49 31 31 14 39 39 8 39 40 28 15 31 21 14 43 38 11 8 8 23 9 11 15 2 11 39 32 14 28 15 40 49 27 9 23 9 9 6 21 2 2 1 14 11 ...

output:

644443122

result:

ok 1 number(s): "644443122"

Test #11:

score: 0
Accepted
time: 679ms
memory: 12712kb

input:

972
39 15 23 0 40 29 43 47 6 9 30 9 2 8 19 9 45 25 26 38 33 18 6 33 44 48 24 8 4 16 33 42 33 31 36 33 13 16 3 12 21 19 1 30 24 23 43 35 0 33 31 32 23 31 36 12 26 0 29 48 28 33 28 28 3 49 9 5 29 8 29 28 49 41 33 49 5 49 6 9 50 25 39 11 1 36 6 44 10 34 32 31 25 31 36 36 3 9 50 35 47 43 25 46 30 18 5 2...

output:

684920840

result:

ok 1 number(s): "684920840"

Test #12:

score: 0
Accepted
time: 108ms
memory: 12724kb

input:

147
34 47 42 23 46 3 41 9 15 42 21 32 24 1 19 46 29 35 38 20 2 43 36 47 19 23 20 9 6 28 48 46 45 21 19 41 31 36 50 7 11 25 0 43 38 46 21 2 26 40 32 14 45 35 47 21 13 26 26 30 3 36 35 45 36 21 21 25 2 40 35 50 23 3 16 44 40 42 6 37 36 19 20 14 30 47 13 49 47 45 26 12 15 21 42 30 19 5 21 9 28 8 3 34 4...

output:

972735235

result:

ok 1 number(s): "972735235"

Test #13:

score: 0
Accepted
time: 664ms
memory: 12580kb

input:

1000
36 15 9 5 35 37 17 30 24 13 18 32 14 35 36 26 23 7 21 15 43 15 21 11 33 33 9 16 5 26 1 45 48 27 20 20 20 48 42 27 22 7 39 35 11 38 33 47 22 34 43 4 32 0 47 35 48 8 9 3 40 3 27 22 20 43 12 37 30 18 2 37 37 35 44 3 42 14 20 24 44 5 17 38 46 41 28 23 21 7 13 15 35 38 21 14 6 37 37 6 13 34 32 13 23...

output:

179933029

result:

ok 1 number(s): "179933029"

Test #14:

score: 0
Accepted
time: 685ms
memory: 12740kb

input:

1000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 7 7 7 7 7 7 7 7 7 7...

output:

540327646

result:

ok 1 number(s): "540327646"

Test #15:

score: 0
Accepted
time: 693ms
memory: 12768kb

input:

1000
50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 49 49 49 49 49 49 49 49 49 49 49 49 49 49 49 49 49 49 49 49 49 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 48 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47 46 46 46 46 46 46 46 46 46 46 46 46 46 4...

output:

169647494

result:

ok 1 number(s): "169647494"

Test #16:

score: 0
Accepted
time: 1310ms
memory: 12652kb

input:

1000
11 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 40 50 50 50 50 50 21 50 12 50 50 50 50 50 0 50 50 50 38 50 50 50 50 50 50 25 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 7 50 50 50 50 50 50 50 50 ...

output:

862643524

result:

ok 1 number(s): "862643524"

Test #17:

score: 0
Accepted
time: 1346ms
memory: 12728kb

input:

1000
50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 5...

output:

819612372

result:

ok 1 number(s): "819612372"

Test #18:

score: 0
Accepted
time: 1342ms
memory: 12604kb

input:

1000
50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 5...

output:

18215579

result:

ok 1 number(s): "18215579"

Test #19:

score: 0
Accepted
time: 5ms
memory: 8392kb

input:

16
0 2 24 1 23 9 14 17 28 29 25 27 15 19 11 20

output:

115090079

result:

ok 1 number(s): "115090079"

Test #20:

score: 0
Accepted
time: 10ms
memory: 12640kb

input:

1000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0...

output:

819612372

result:

ok 1 number(s): "819612372"

Test #21:

score: 0
Accepted
time: 6ms
memory: 6912kb

input:

18
9 4 21 5 22 6 9 16 3 14 11 2 0 12 6 3 7 21

output:

0

result:

ok 1 number(s): "0"

Extra Test:

score: 0
Extra Test Passed