| # | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1090043 | 2024-09-17T16:01:40 Z | KALARRY | COVID tests (CEOI24_covid) | C++14 | 4016 ms | 344 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;
while(pos < N)
{
for(int b = (N - pos + 1)/5 ; b >= 1 ; b/=2)
while(pos + b < N)
{
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
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 | Incorrect | 49 ms | 344 KB | Output isn't correct |
| 2 | Halted | 0 ms | 0 KB | - |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 53 ms | 344 KB | Output is correct (P=0.001, F=15.1, Q=24.2) -> 26.39 points |
| 2 | Correct | 199 ms | 344 KB | Output is correct (P=0.005256, F=51.1, Q=83.3) -> 25.56 points |
| 3 | Correct | 367 ms | 344 KB | Output is correct (P=0.011546, F=94.9, Q=166.2) -> 22.47 points |
| 4 | Correct | 852 ms | 344 KB | Output is correct (P=0.028545, F=191.5, Q=377.5) -> 18.42 points |
| 5 | Correct | 1204 ms | 344 KB | Output is correct (P=0.039856, F=246.3, Q=519.0) -> 16.58 points |
| 6 | Correct | 1980 ms | 344 KB | Output is correct (P=0.068648, F=366.2, Q=853.9) -> 14.22 points |
| 7 | Correct | 3040 ms | 344 KB | Output is correct (P=0.104571, F=490.3, Q=1265.9) -> 12.28 points |
| 8 | Execution timed out | 4016 ms | 344 KB | Time limit exceeded (wall clock) |
| 9 | Halted | 0 ms | 0 KB | - |