#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define chkmin(a, b) a = min(a, b)
#define chkmax(a, b) a = max(a, b)
using namespace std;
typedef long long ll;
typedef vector<ll> vi;
typedef vector<vi> vvi;
typedef pair<ll, ll> pii;
typedef vector<pii> vii;
typedef vector<bool> vb;
/// 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.
//void Solve(int l, int r, vb &ans) {
// vb test(n);
// fill(test.begin() + l, test.begin() + r, 1);
// bool b = test_students(test);
// if (!b) return;
// if (l + 1 == r) {
// ans[l] = 1;
// return;
// }
// Solve(l, (l + r) >> 1, ans);
// Solve((l + r) >> 1, r, ans);
//}
mt19937 rng(time(0));
int FindNext(int l, int r, vi &ind) {
vb mask(n);
for (int i = l; i < r; i++) mask[ind[i]] = 1;
if (!test_students(mask)) return r;
for (int i = l; i < r; i++) mask[ind[i]] = 0;
int begin = l + 1, end = r;
while (begin < end) {
int mid = (begin + end) >> 1;
for (int i = l; i < mid; i++) mask[ind[i]] = 1;
if (test_students(mask)) end = mid;
else begin = mid + 1;
for (int i = l; i < mid; i++) mask[ind[i]] = 0;
}
return end - 1;
}
void Solve(int l, int r, vi &ind, vb &ans) {
while (l < r) {
int nx = FindNext(l, r, ind);
ans[nx] = 1;
l = nx + 1;
}
}
vb find_positive() {
vb ans(n);
vi ind(n);
iota(all(ind), 0);
while (!ind.empty()) {
vi nx;
shuffle(all(ind), rng);
int m = ind.size();
int blocks = min<int>(m, ceil(m * P * 2));
int len = (m + blocks - 1) / blocks;
for (int i = 0; i < m; i += len) {
// Solve(i, min(i + len, n), ans);
int l = i, r = min(i + len, m);
int j = FindNext(l, r, ind);
if (j < r) ans[ind[j++]] = 1;
for (int k = j; k < r; k++) nx.push_back(ind[k]);
}
swap(ind, nx);
}
return ans;
// int block = 1000;
// for (int i = 0; i < n; i += block) Solve(i, i + block, ans);
// Solve(0, n, answer);
// vb test(n);
// for (int i = 0; i < n; i++) {
// test[i] = 1;
// answer[i] = test_students(test);
// test[i] = 0;
// }
return ans;
}
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++) {
vb 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;
}
Compilation message
Main.cpp: In function 'bool test_students(std::vector<bool>)':
Main.cpp:38:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
38 | scanf(" %c", &answer);
| ~~~~~^~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:123:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
123 | scanf("%d %lf %d", &n, &P, &T);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:139:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
139 | scanf(" %c", &verdict);
| ~~~~~^~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
344 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
344 KB |
Output is correct |
| 2 |
Correct |
6 ms |
344 KB |
Output is correct |
| 3 |
Correct |
6 ms |
344 KB |
Output is correct |
| 4 |
Correct |
5 ms |
344 KB |
Output is correct |
| 5 |
Correct |
5 ms |
344 KB |
Output is correct |
| 6 |
Correct |
5 ms |
344 KB |
Output is correct |
| 7 |
Correct |
8 ms |
344 KB |
Output is correct |
| 8 |
Correct |
5 ms |
600 KB |
Output is correct |
| 9 |
Correct |
5 ms |
344 KB |
Output is correct |
| 10 |
Correct |
5 ms |
344 KB |
Output is correct |
| 11 |
Correct |
5 ms |
344 KB |
Output is correct |
| 12 |
Correct |
7 ms |
344 KB |
Output is correct |
| 13 |
Correct |
5 ms |
344 KB |
Output is correct |
| 14 |
Correct |
5 ms |
344 KB |
Output is correct |
| 15 |
Correct |
6 ms |
344 KB |
Output is correct |
| 16 |
Correct |
6 ms |
344 KB |
Output is correct |
| 17 |
Runtime error |
0 ms |
344 KB |
Execution killed with signal 8 |
| 18 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
344 KB |
Output is correct (P=0.001, F=15.1, Q=10.9) -> 90.00 points |
| 2 |
Correct |
92 ms |
344 KB |
Output is correct (P=0.005256, F=51.1, Q=47.6) -> 90.00 points |
| 3 |
Correct |
169 ms |
432 KB |
Output is correct (P=0.011546, F=94.9, Q=92.9) -> 90.00 points |
| 4 |
Correct |
362 ms |
424 KB |
Output is correct (P=0.028545, F=191.5, Q=191.7) -> 89.63 points |
| 5 |
Correct |
501 ms |
592 KB |
Output is correct (P=0.039856, F=246.3, Q=249.5) -> 85.55 points |
| 6 |
Correct |
710 ms |
428 KB |
Output is correct (P=0.068648, F=366.2, Q=366.7) -> 89.51 points |
| 7 |
Correct |
1076 ms |
604 KB |
Output is correct (P=0.104571, F=490.3, Q=505.9) -> 79.84 points |
| 8 |
Correct |
1201 ms |
428 KB |
Output is correct (P=0.158765, F=639.1, Q=633.8) -> 90.00 points |
| 9 |
Correct |
1587 ms |
344 KB |
Output is correct (P=0.2, F=731.4, Q=760.2) -> 77.75 points |
