| # | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1090049 | 2024-09-17T16:12:41 Z | KALARRY | COVID tests (CEOI24_covid) | C++14 | 7000 ms | 596 KB |
#include <cassert>
#include <cstdio>
#include <string>
#include <vector>
#include<bits/stdc++.h>
using namespace std;
/// You may use:
// The number of students
int N;
// 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> find_positive() {
std::vector<bool> answer(N);
vector<bool> mask;
int total_pos = floor(N*P);
int rem = total_pos;
for(int i = 0 ; i < N ; i++)
mask.push_back(false);
int pos = 0;
int expect_to_reach = 0;
double val = (1-P);
while(val > 0.4)
{
expect_to_reach++;
val *= (1-P);
}
while(pos < N)
{
int reach = N-1;
for(int b = expect_to_reach ; b >= 1 ; b/=2)
while(pos + b <= reach)
{
for(int i = pos ; i <= pos + b ; i++)
mask[i] = true;
bool res = test_students(mask);
for(int i = pos ; i <= pos + b ; i++)
mask[i] = false;
if(!res)
{
for(int i = pos ; i <= pos + b ; i++)
answer[i] = false;
pos += (b+1);
}
else
{
reach = pos + b -1;
break;
}
}
mask[pos] = true;
bool res = test_students(mask);
answer[pos] = res;
mask[pos] = false;
pos++;
rem--;
}
return answer;
}
int main() {
int T;
scanf("%d %lf %d", &N, &P, &T);
// You may perform any extra initialization here.
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 | 0 ms | 344 KB | Output is correct |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 5 ms | 344 KB | Output is correct |
| 2 | Correct | 8 ms | 344 KB | Output is correct |
| 3 | Correct | 6 ms | 344 KB | Output is correct |
| 4 | Correct | 7 ms | 344 KB | Output is correct |
| 5 | Correct | 6 ms | 344 KB | Output is correct |
| 6 | Correct | 6 ms | 344 KB | Output is correct |
| 7 | Correct | 10 ms | 344 KB | Output is correct |
| 8 | Correct | 8 ms | 596 KB | Output is correct |
| 9 | Correct | 9 ms | 344 KB | Output is correct |
| 10 | Correct | 5 ms | 344 KB | Output is correct |
| 11 | Correct | 7 ms | 344 KB | Output is correct |
| 12 | Correct | 13 ms | 344 KB | Output is correct |
| 13 | Correct | 11 ms | 344 KB | Output is correct |
| 14 | Correct | 8 ms | 344 KB | Output is correct |
| 15 | Correct | 8 ms | 344 KB | Output is correct |
| 16 | Correct | 7 ms | 344 KB | Output is correct |
| 17 | Execution timed out | 7050 ms | 344 KB | Time limit exceeded |
| 18 | Halted | 0 ms | 0 KB | - |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 42 ms | 344 KB | Output is correct (P=0.001, F=15.1, Q=19.3) -> 42.60 points |
| 2 | Correct | 158 ms | 344 KB | Output is correct (P=0.005256, F=51.1, Q=66.3) -> 41.10 points |
| 3 | Correct | 317 ms | 344 KB | Output is correct (P=0.011546, F=94.9, Q=131.6) -> 35.34 points |
| 4 | Correct | 659 ms | 344 KB | Output is correct (P=0.028545, F=191.5, Q=275.0) -> 32.80 points |
| 5 | Correct | 801 ms | 344 KB | Output is correct (P=0.039856, F=246.3, Q=347.0) -> 34.15 points |
| 6 | Correct | 1333 ms | 344 KB | Output is correct (P=0.068648, F=366.2, Q=536.6) -> 31.45 points |
| 7 | Correct | 1730 ms | 344 KB | Output is correct (P=0.104571, F=490.3, Q=734.5) -> 30.08 points |
| 8 | Correct | 2165 ms | 344 KB | Output is correct (P=0.158765, F=639.1, Q=928.1) -> 32.04 points |
| 9 | Correct | 2690 ms | 344 KB | Output is correct (P=0.2, F=731.4, Q=1134.7) -> 28.08 points |