#include <cassert>
#include <cstdio>
#include <string>
#include <vector>
#include <bits/stdc++.h>
typedef long long ll;
#define FOR(i,x,y) for(ll i=x; i<y; i++)
#define FORNEG(i,x,y) for(ll i=x; i>y; i--)
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';
}
vector<ll> dp(ll a, ll b, bool result){
//cout << a << " " << b << " " << result << endl;
if (result == 0) return {};
if (a==b){
if (result == 1) return {a};
else return {};
}
ll mid = (a+b)/2;
vector<ll> temp, temp2;
vector<bool> test(N), test2(N);
FOR(i,a,mid+1) test[i] = 1;
FOR(i,mid+1,b+1) test2[i] = 1;
if (rand()%2==0){
ll result1 = test_students(test);
temp = dp(a, mid, result1);
ll result2 = -1;
if (result1==0) result2 = 1;
else result2 = test_students(test2);
temp2 = dp(mid+1, b, result2);
}else{
ll result2 = test_students(test2);
ll result1 = -1;
temp2 = dp(mid+1, b, result2);
if (result2==0) result1 = 1;
else result1 = test_students(test);
temp = dp(a, mid, result2);
}
vector<ll> ans;
for (auto&i : temp) ans.push_back(i);
for (auto&i : temp2) ans.push_back(i);
return ans;
}
std::vector<bool> find_positive() {
std::vector<bool> answer(N);
vector<ll> stuff;
vector<ll> temp;
ll c;
if (P>=0.068648) c = 4;
else c = 1000;
//cout << c << endl;
FOR(i,0,(N-1)/c + 1){
ll a = c*i;
ll b = min(c*(i+1)-1, (ll)N-1);
vector<bool> test(N);
FOR(j,a,b+1) test[j] = 1;
temp = dp(a, b, test_students(test));
for (auto&k : temp) stuff.push_back(k);
}
FOR(i,0,N) answer[i] = 0;
for (auto&i : stuff) answer[i] = 1;
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
Main.cpp: In function 'std::vector<long long int> dp(ll, ll, bool)':
Main.cpp:62:12: warning: variable 'result1' set but not used [-Wunused-but-set-variable]
62 | ll result1 = -1;
| ^~~~~~~
Main.cpp: In function 'bool test_students(std::vector<bool>)':
Main.cpp:35:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
35 | scanf(" %c", &answer);
| ~~~~~^~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:105:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
105 | scanf("%d %lf %d", &N, &P, &T);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:121:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
121 | scanf(" %c", &verdict);
| ~~~~~^~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
344 KB |
translate:wrong |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
344 KB |
translate:wrong |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
344 KB |
translate:wrong |
| 2 |
Halted |
0 ms |
0 KB |
- |
