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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
#446443#8526. Polygon IIPhantomThresholdAC ✓334ms4324kbC++171.8kb2024-06-17 10:44:512024-06-17 10:44:53

Judging History

你现在查看的是最新测评结果

  • [2024-06-17 10:44:53]
  • 评测
  • 测评结果:AC
  • 用时:334ms
  • 内存:4324kb
  • [2024-06-17 10:44:51]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
const ll mod=1000000007;
const ll inv2=(mod+1)/2;
inline ll ksm(ll a,ll x){
	ll ret=1;
	for (;x;x>>=1,a=a*a%mod) if (x&1) ret=ret*a%mod;
	return ret;
}
inline ll inv(ll a){return ksm(a,mod-2);}
void add(ll &A,ll B){A+=B;if (A>=mod) A-=mod;}
void sub(ll &A,ll B){A-=B;if (A<0) A+=mod;}

const int maxn=2000;
ll fac[maxn+50];
ll ifac[maxn+50];
void prepare(){
	fac[0]=1;
	for (int i=1;i<=maxn;i++) fac[i]=fac[i-1]*i%mod;
	ifac[maxn]=inv(fac[maxn]);
	for (int i=maxn-1;i>=0;i--) ifac[i]=ifac[i+1]*(i+1)%mod;
//	for (int i=0;i<=5;i++) cout << fac[i] << " ";
//	cout << endl;
//	for (int i=0;i<=5;i++) cout << ifac[i] << " ";
//	cout << endl;	
}
ll C(ll n,ll m){
	if (m<0 || m>n) return 0;
	return fac[n]*ifac[m]%mod*ifac[n-m]%mod;	
}

ll n;
ll a[maxn+50];
ll cnt[55];
ll sum[55];
ll dp[55][maxn+50];

int main(){
	ios_base::sync_with_stdio(false);
	prepare();
	cin >> n;
	for (int i=1;i<=n;i++){
		cin >> a[i];
		for (int j=0;j<a[i];j++) cnt[j]++;	
	}
	for (int i=50;i>=0;i--) sum[i]=sum[i+1]+cnt[i];
	for (int i=1;i<=n;i++){
		for (int j=0;j<=i;j++){
			ll res=ksm(i-j,n)*C(n,j)%mod*ifac[n]%mod;
			if (j%2==0) add(dp[0][i-1],res);
			else sub(dp[0][i-1],res);
		}
	}
	for (int i=n-1;i>=1;i--) sub(dp[0][i],dp[0][i-1]);
	
	int lim=n-1;
	for (int i=0;i<=50;i++){
		ll invr=ksm(inv2,cnt[i]);
		int mx=0;
		for (int j=0;j<=lim;j++){
			for (int l=0;l<=cnt[i];l++){
				ll coef=C(cnt[i],l)*invr%mod;
				int index=(j+l)/2;
				mx=max(mx,index);
				add(dp[i+1][index],dp[i][j]*coef%mod);
			}
		}
		lim=mx;
	}
	ll ans=0;
	for (int i=1;i<=n;i++){
		add(ans,dp[a[i]][0]*ksm(inv2,sum[a[i]])%mod);
	}
	ans=(mod+1-ans)%mod;
	cout << ans << "\n";
	return 0;
}

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 3944kb

input:

3
0 2 0

output:

166666668

result:

ok 1 number(s): "166666668"

Test #2:

score: 0
Accepted
time: 1ms
memory: 3904kb

input:

3
0 0 0

output:

500000004

result:

ok 1 number(s): "500000004"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3880kb

input:

3
5 6 7

output:

208333335

result:

ok 1 number(s): "208333335"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3812kb

input:

3
0 25 50

output:

889268532

result:

ok 1 number(s): "889268532"

Test #5:

score: 0
Accepted
time: 1ms
memory: 3816kb

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: 1ms
memory: 3828kb

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: 2ms
memory: 3948kb

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: 48ms
memory: 3912kb

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: 166ms
memory: 4100kb

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: 118ms
memory: 4000kb

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: 127ms
memory: 4040kb

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: 4ms
memory: 3816kb

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: 127ms
memory: 4036kb

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: 133ms
memory: 3984kb

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: 128ms
memory: 3988kb

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: 321ms
memory: 4324kb

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: 330ms
memory: 4284kb

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: 334ms
memory: 4232kb

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: 1ms
memory: 3940kb

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: 21ms
memory: 3904kb

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: 1ms
memory: 3828kb

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