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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#521798 | #9162. COVID tests | Dan4Life | 0 | 661ms | 4120kb | C++23 | 2.6kb | 2024-08-16 15:08:53 | 2024-08-16 15:08:53 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) begin(a), end(a)
using ll = long long;
using vi = vector<int>;
using ar2 = array<int,2>;
using ar3 = array<int,3>;
using ar4 = array<int,4>;
const int INF = (int)2e9;
const int mxN = (int)1e6+10;
int N;
double P;
map<vector<bool>,bool> M;
// 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);
//if(M.count(mask)) return M[mask];
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.
vector<bool> find_positive() {
vector<bool> answer(N,false), test(N,false);
vector<int> XD(N,0); iota(all(XD),0); random_shuffle(all(XD));
double prob = 1.0-P;
int B = 1;
while(prob<0.5) prob*=(1.0-P), B++;
for(int i = 0; i < N; i+=B){
int l = i, r = min(N,i+B);
for(int j = l; j < r; j++) test[XD[j]]=1;
if(!test_students(test)) continue;
while(l<min(N,i+B)){
r = min(N,i+B);
while(l<r){
int mid = (l+r)/2;
for(int j = l; j <= mid; j++) test[XD[j]]=1;
if(test_students(test)){
r=mid;
for(int j = l; j <= mid; j++) test[XD[j]]=0;
}
else l=mid+1;
}
answer[XD[l]]=1; l++;
}
for(int j = i; j < min(N,i+B); j++) test[XD[j]]=0;
}
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++) {
vector<bool> answer = find_positive();
assert(answer.size() == (size_t)N);
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;
}
Details
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Subtask #1:
score: 0
Time Limit Exceeded
Test #1:
score: 0
Time Limit Exceeded
input:
1000 0.789673 1
output:
result:
Subtask #2:
score: 0
Wrong Answer
Test #18:
score: 0
Wrong Answer
time: 661ms
memory: 4120kb
input:
1000 0.001 300 N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N...
output:
Q 0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000...
result:
points 0.0 0.0 translate:wrong