#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.
int test_students(std::vector<int> 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<int> find_positive() {
vector<int> ans(N);
vector<int> order(N);
mt19937 rng(69420);
iota(order.begin(), order.end(), 0);
shuffle(order.begin(), order.end(), rng);
auto query=[&](int l, int r) -> int {
vector<int> test(N);
for (int i=l; i<=r; ++i) test[order[i]]=1;
return test_students(test);
};
int block=3;
auto solve=[&](auto &&self, int l, int r) -> void {
if (l>r) return;
if (!query(l, r)) return;
if (l==r){
ans[order[l]]=1;
return;
}
vector<int> sz(block, (r-l+1)/block);
for (int i=0; i<(r-l+1)%block; ++i) ++sz[i];
for (int i:sz) self(self, l, l+i-1), l+=i;
};
solve(solve, 0, N-1);
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++) {
std::vector<int> 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
Main.cpp: In function 'int test_students(std::vector<int>)':
Main.cpp:33:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
33 | scanf(" %c", &answer);
| ~~~~~^~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:72:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
72 | scanf("%d %lf %d", &N, &P, &T);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:88:12: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
88 | scanf(" %c", &verdict);
| ~~~~~^~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
596 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
9 ms |
344 KB |
Output is correct |
| 2 |
Correct |
9 ms |
344 KB |
Output is correct |
| 3 |
Correct |
11 ms |
344 KB |
Output is correct |
| 4 |
Correct |
9 ms |
344 KB |
Output is correct |
| 5 |
Correct |
9 ms |
344 KB |
Output is correct |
| 6 |
Correct |
14 ms |
344 KB |
Output is correct |
| 7 |
Correct |
10 ms |
344 KB |
Output is correct |
| 8 |
Correct |
7 ms |
344 KB |
Output is correct |
| 9 |
Correct |
8 ms |
344 KB |
Output is correct |
| 10 |
Correct |
5 ms |
344 KB |
Output is correct |
| 11 |
Correct |
11 ms |
344 KB |
Output is correct |
| 12 |
Correct |
8 ms |
344 KB |
Output is correct |
| 13 |
Correct |
8 ms |
344 KB |
Output is correct |
| 14 |
Correct |
10 ms |
344 KB |
Output is correct |
| 15 |
Correct |
8 ms |
344 KB |
Output is correct |
| 16 |
Correct |
10 ms |
344 KB |
Output is correct |
| 17 |
Correct |
0 ms |
344 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
35 ms |
344 KB |
Output is correct (P=0.001, F=15.1, Q=16.7) -> 63.21 points |
| 2 |
Correct |
173 ms |
344 KB |
Output is correct (P=0.005256, F=51.1, Q=72.0) -> 34.14 points |
| 3 |
Correct |
339 ms |
344 KB |
Output is correct (P=0.011546, F=94.9, Q=139.1) -> 31.44 points |
| 4 |
Correct |
691 ms |
344 KB |
Output is correct (P=0.028545, F=191.5, Q=276.8) -> 32.35 points |
| 5 |
Correct |
893 ms |
344 KB |
Output is correct (P=0.039856, F=246.3, Q=354.8) -> 32.58 points |
| 6 |
Correct |
1248 ms |
344 KB |
Output is correct (P=0.068648, F=366.2, Q=515.7) -> 34.18 points |
| 7 |
Correct |
1585 ms |
344 KB |
Output is correct (P=0.104571, F=490.3, Q=677.4) -> 35.62 points |
| 8 |
Correct |
2013 ms |
344 KB |
Output is correct (P=0.158765, F=639.1, Q=860.4) -> 37.73 points |
| 9 |
Correct |
2284 ms |
344 KB |
Output is correct (P=0.2, F=731.4, Q=980.3) -> 38.12 points |
