| # | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1090439 | 2024-09-18T11:05:40 Z | lucri | COVID tests (CEOI24_covid) | C++17 | 2126 ms | 448 KB |
#include <bits/stdc++.h>
/// You may use:
// The number of students
int N,T;
// The probability any given student is positive
double P;
// This function performs a test on a subset of samples.
// Its argument is a vector of Booleans of length N,
// where the i-th element is true if the i-th sample should be added to the mix.
// It returns true if (and only if) at least one of the samples in the mix is positive.
bool test_students(std::vector<bool> mask) {
assert(mask.size() == (size_t)N);
std::string mask_str(N, ' ');
for (int i = 0; i < N; i++)
mask_str[i] = mask[i] ? '1' : '0';
printf("Q %s\n", mask_str.c_str());
fflush(stdout);
char answer;
scanf(" %c", &answer);
return answer == 'P';
}
/// You should implement:
// This function will be called once for each test instance.
// It should use test_students to determine which samples are positive.
// It must return a vector of Booleans of length N,
// where the i-th element is true if and only if the i-th sample is positive.
std::vector<bool> answer;
std::vector<bool> test;
std::vector<int> ind;
int p[5010];
void calculeaza(int b,int e,int sz)
{
if(b>e)
return;
int ce=e;
e=b+2*sz-1;
while(e>p[0])
{
++p[0];
p[p[0]]=p[p[0]]=ce;
}
while(b<e)
{
if(b>ce)
return;
int mid=(b+e)/2;
for(int i=b;i<=mid;++i)
test[p[i]]=1;
bool r=test_students(test);
for(int i=b;i<=mid;++i)
test[p[i]]=0;
if(r==false)
b=mid+1;
else
e=mid;
}
if(b<=ce)
{
answer[p[b]]=1;
calculeaza(b+1,ce,sz);
}
return;
}
void raspunde(int sz)
{
p[0]=0;
for(int i=0;i<N;i+=sz)
{
for(int j=i;j<i+sz&&j<N;++j)
test[ind[j]]=1;
if(test_students(test)==true)
{
for(int j=i;j<i+sz&&j<N;++j)
p[++p[0]]=ind[j];
}
for(int j=i;j<i+sz&&j<N;++j)
test[ind[j]]=0;
}
calculeaza(1,p[0],sz);
}
std::vector<bool> find_positive()
{
for(int i=0;i<N;++i)
{
answer[i]=test[i]=0;
ind[i]=i;
}
random_shuffle(ind.begin(),ind.end());
if(T==1)//subtask 1
{
raspunde(1);
}
else if(P>0.17)//P=0.2
{
raspunde(4);
}
else if(P>0.11)//P=0.158765
{
raspunde(6);
}
else if(P>0.1)//P=0.104571
{
raspunde(6);
}
else if(P>0.06)//P=0.068648
{
raspunde(10);
}
else if(P>0.03)//P=0.039856
{
raspunde(17);
}
else if(P>0.02)//P=0.028545
{
raspunde(24);
}
else if(P>0.01)//P=0.011546
{
raspunde(58);
}
else if(P>0.005)///P=0.005256
{
raspunde(200);
}
else///P=0.001
{
raspunde(500);
}
return answer;
}
int main() {
scanf("%d %lf %d", &N, &P, &T);
// You may perform any extra initialization here.
srand(time(0));
answer.resize(N);
ind.resize(N);
test.resize(N);
for (int i = 0; i < T; i++) {
std::vector<bool> answer = find_positive();
assert(answer.size() == (size_t)N);
std::string answer_str(N, ' ');
for (int j = 0; j < N; j++)
answer_str[j] = answer[j] ? '1' : '0';
printf("A %s\n", answer_str.c_str());
fflush(stdout);
char verdict;
scanf(" %c", &verdict);
if (verdict == 'W')
exit(0);
}
return 0;
}
Compilation message
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 1 ms | 344 KB | Output is correct |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 11 ms | 444 KB | Output is correct |
| 2 | Correct | 9 ms | 444 KB | Output is correct |
| 3 | Correct | 11 ms | 344 KB | Output is correct |
| 4 | Correct | 11 ms | 344 KB | Output is correct |
| 5 | Correct | 11 ms | 344 KB | Output is correct |
| 6 | Correct | 12 ms | 444 KB | Output is correct |
| 7 | Correct | 9 ms | 344 KB | Output is correct |
| 8 | Correct | 8 ms | 344 KB | Output is correct |
| 9 | Correct | 9 ms | 344 KB | Output is correct |
| 10 | Correct | 8 ms | 344 KB | Output is correct |
| 11 | Correct | 8 ms | 344 KB | Output is correct |
| 12 | Correct | 8 ms | 344 KB | Output is correct |
| 13 | Correct | 12 ms | 344 KB | Output is correct |
| 14 | Correct | 11 ms | 344 KB | Output is correct |
| 15 | Correct | 12 ms | 344 KB | Output is correct |
| 16 | Correct | 14 ms | 448 KB | Output is correct |
| 17 | Correct | 6 ms | 344 KB | Output is correct |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 36 ms | 344 KB | Output is correct (P=0.001, F=15.1, Q=11.7) -> 90.00 points |
| 2 | Correct | 121 ms | 344 KB | Output is correct (P=0.005256, F=51.1, Q=50.3) -> 90.00 points |
| 3 | Correct | 249 ms | 344 KB | Output is correct (P=0.011546, F=94.9, Q=97.8) -> 80.20 points |
| 4 | Correct | 531 ms | 344 KB | Output is correct (P=0.028545, F=191.5, Q=204.4) -> 70.90 points |
| 5 | Correct | 657 ms | 416 KB | Output is correct (P=0.039856, F=246.3, Q=266.9) -> 67.44 points |
| 6 | Correct | 1020 ms | 416 KB | Output is correct (P=0.068648, F=366.2, Q=408.0) -> 61.79 points |
| 7 | Correct | 1484 ms | 416 KB | Output is correct (P=0.104571, F=490.3, Q=556.9) -> 58.32 points |
| 8 | Correct | 1755 ms | 344 KB | Output is correct (P=0.158765, F=639.1, Q=754.6) -> 52.24 points |
| 9 | Correct | 2126 ms | 344 KB | Output is correct (P=0.2, F=731.4, Q=853.2) -> 54.02 points |