QOJ.ac
QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #210028 | #5740. Testing Subjects Usually Die | ExplodingKonjac | WA | 1ms | 3708kb | C++20 | 1.1kb | 2023-10-10 22:10:59 | 2023-10-10 22:11:01 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
using LL=long long;
using LD=long double;
using UI=unsigned int;
using ULL=unsigned long long;
#ifndef DADALZY
#define FILEIO(file) freopen(file".in","r",stdin),freopen(file".out","w",stdout)
#define LOG(...) void()
#else
#define FILEIO(file)
#define LOG(...) fprintf(stderr,__VA_ARGS__)
#endif
int n;
double c,p[100005],q[100005],sp[100005];
int main()
{
cin>>n>>c,c/=100;
double sum=0;
for(int i=1;i<=n;i++) cin>>p[i],sum+=p[i];
for(int i=1;i<=n;i++) p[i]/=sum;
sort(p+1,p+n+1);
for(int i=1;i<=n;i++) sp[i]=sqrt(p[i]);
double ans=0;
if(c==1) ans=1/p[n];
else
{
auto calcq=[&](double C)
{
double sum=0;
for(int i=1;i<=n;i++)
q[i]=(C*sp[i]-c)/(1-c),sum+=q[i];
return sum;
};
double l=0,r=1e9;
for(int _=0;_<100;_++)
{
double mid=(l+r)/2;
if(calcq(mid)<=1) l=mid;
else r=mid;
}
calcq(l);
double sf=0,sg=0;
for(int i=1;i<=n;i++)
{
sf+=p[i]/(c+(1-c)*q[i]);
sg+=p[i]*q[i]/(c+(1-c)*q[i]);
}
ans=sf/sg;
}
cout<<setprecision(8)<<fixed<<ans<<'\n';
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 1ms
memory: 3696kb
input:
4 100 25 25 25 25
output:
4.00000000
result:
ok found '4.0000000', expected '4.0000000', error '0.0000000'
Test #2:
score: 0
Accepted
time: 1ms
memory: 3696kb
input:
2 0 1 4
output:
1.80000000
result:
ok found '1.8000000', expected '1.8000000', error '0.0000000'
Test #3:
score: 0
Accepted
time: 0ms
memory: 3644kb
input:
5 0 245 802 95 452 756
output:
4.46853100
result:
ok found '4.4685310', expected '4.4685310', error '0.0000000'
Test #4:
score: 0
Accepted
time: 1ms
memory: 3648kb
input:
5 10 85 144 62 67 925
output:
3.08233733
result:
ok found '3.0823373', expected '3.0823373', error '0.0000000'
Test #5:
score: 0
Accepted
time: 0ms
memory: 3708kb
input:
5 20 573 598 705 893 279
output:
4.66556407
result:
ok found '4.6655641', expected '4.6655641', error '0.0000000'
Test #6:
score: 0
Accepted
time: 0ms
memory: 3632kb
input:
5 25 533 195 166 109 527
output:
3.93380793
result:
ok found '3.9338079', expected '3.9338079', error '0.0000000'
Test #7:
score: -100
Wrong Answer
time: 0ms
memory: 3640kb
input:
5 50 498 942 71 637 663
output:
2.98972856
result:
wrong answer 1st numbers differ - expected: '3.8718857', found: '2.9897286', error = '0.2278366'