#include <cassert>
#include <cstdio>
#include <string>
#include <vector>
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:
void rec(int l, int r, vector<bool>& answer)
{
vector<bool> v(N, false);
for (int i = l; i <= r; ++i)
v[i] = true;
if (test_students(v) == false)
return;
if (l == r)
{
answer[l] = true;
return;
}
int m = (l + r) / 2;
rec(l, m, answer);
rec(m + 1, r, answer);
}
void solv0(vector<bool>& answer)
{
int s = 0;
while (s < N)
{
int l = s, r = N - 1;
vector<bool> v(N, false);
for (int i = l; i <= r; ++i)
v[i] = true;
if (!test_students(v))
break;
int u;
while (l <= r)
{
int m = (l + r) / 2;
vector<bool> v(N, false);
for (int i = s; i <= m; ++i)
v[i] = true;
if (test_students(v))
{
u = m;
r = m - 1;
}
else
l = m + 1;
}
answer[u] = true;
s = u + 1;
}
}
// 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, false);
if (P < 0.007)
solv0();
else
rec(0, N - 1, answer);
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;
}
// 1000 0.001 300
Compilation message
Main.cpp: In function 'std::vector<bool> find_positive()':
Main.cpp:91:15: error: too few arguments to function 'void solv0(std::vector<bool>&)'
91 | solv0();
| ^
Main.cpp:53:6: note: declared here
53 | void solv0(vector<bool>& answer)
| ^~~~~
Main.cpp: In function 'bool test_students(std::vector<bool>)':
Main.cpp:30:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
30 | scanf(" %c", &answer);
| ~~~~~^~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:99:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
99 | scanf("%d %lf %d", &N, &P, &T);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:115:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
115 | scanf(" %c", &verdict);
| ~~~~~^~~~~~~~~~~~~~~~~
