#include <cassert>
#include <cstdio>
#include <string>
#include <vector>
#include <bits/stdc++.h>
using namespace std;;
/// You may use:
string s;
// 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 loc = 0;
bool test_students(std::vector<bool> mask) {
if(loc) {
bool ans = false;
for(int i = 0; i < N; i++) {
if(mask[i] && s[i] == '1') {
ans = 1;
}
}
return ans;
}
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:
mt19937 rng(123321);
// 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.
bool as(int l,int r) {
vector<bool> ask(N,0);
for(int i = l;i <= min(N - 1,r);i++) {
ask[i] = 1;
}
return test_students(ask);
}
std::vector<bool> find_positive() {
vector<bool> answer(N),ask(N,0);
function<void(int,int)>go1 = [&](int l,int r) {
if(l == r) {
answer[l] = 1;
return;
}
int mid = (l + r) >> 1;
if(as(l,mid)) {
go1(l,mid);
}
if(as(mid+1,r)) go1(mid+1,r);
};
function<int(int,int)>go = [&](int l,int r) {
if(l == r) {
answer[l] = 1;
return l;
}
int mid = (l + r) / 2;
if(as(l,mid)) {
return go(l,mid);
}
return go(mid+1,r);
};
auto solve = [&](int b) {
int i = 0;
while(i < N) {
int r = min(N - 1,i + b);
if(as(i,r)) {
go1(i,r);
}
i = r + 1;
}
};
if(P == 0) {
return answer;
}
if(P > 0.2){
solve(70);
return answer;
}
int b;
if(P != 0.068648) {
b = (int)(0.60 / P);
} else {
b = (int)(0.63 / P);
}
int i = 0;
while(i < N) {
int r = min(i + b,N - 1);
if(as(i,r)) {
i = go(i,r)+1;
} else {
i = r + 1;
}
}
return answer;
}
int main() {
int T;
scanf("%d %lf %d", &N, &P, &T);
if(loc) cin >> s;
// 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 'bool test_students(std::vector<bool>)':
Main.cpp:38:14: 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:117:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
117 | scanf("%d %lf %d", &N, &P, &T);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:133:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
133 | scanf(" %c", &verdict);
| ~~~~~^~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
344 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
12 ms |
344 KB |
Output is correct |
| 2 |
Correct |
18 ms |
344 KB |
Output is correct |
| 3 |
Correct |
15 ms |
344 KB |
Output is correct |
| 4 |
Correct |
16 ms |
344 KB |
Output is correct |
| 5 |
Correct |
11 ms |
344 KB |
Output is correct |
| 6 |
Correct |
11 ms |
344 KB |
Output is correct |
| 7 |
Correct |
10 ms |
340 KB |
Output is correct |
| 8 |
Correct |
12 ms |
344 KB |
Output is correct |
| 9 |
Correct |
11 ms |
344 KB |
Output is correct |
| 10 |
Correct |
4 ms |
344 KB |
Output is correct |
| 11 |
Correct |
9 ms |
344 KB |
Output is correct |
| 12 |
Correct |
9 ms |
344 KB |
Output is correct |
| 13 |
Correct |
11 ms |
344 KB |
Output is correct |
| 14 |
Correct |
9 ms |
344 KB |
Output is correct |
| 15 |
Correct |
11 ms |
340 KB |
Output is correct |
| 16 |
Correct |
14 ms |
344 KB |
Output is correct |
| 17 |
Correct |
0 ms |
344 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
33 ms |
340 KB |
Output is correct (P=0.001, F=15.1, Q=10.9) -> 90.00 points |
| 2 |
Correct |
138 ms |
344 KB |
Output is correct (P=0.005256, F=51.1, Q=46.8) -> 90.00 points |
| 3 |
Correct |
189 ms |
344 KB |
Output is correct (P=0.011546, F=94.9, Q=91.6) -> 90.00 points |
| 4 |
Correct |
405 ms |
344 KB |
Output is correct (P=0.028545, F=191.5, Q=190.4) -> 90.00 points |
| 5 |
Correct |
520 ms |
344 KB |
Output is correct (P=0.039856, F=246.3, Q=244.0) -> 90.00 points |
| 6 |
Correct |
817 ms |
344 KB |
Output is correct (P=0.068648, F=366.2, Q=373.1) -> 83.69 points |
| 7 |
Correct |
1103 ms |
344 KB |
Output is correct (P=0.104571, F=490.3, Q=499.5) -> 83.72 points |
| 8 |
Correct |
1406 ms |
344 KB |
Output is correct (P=0.158765, F=639.1, Q=633.1) -> 90.00 points |
| 9 |
Correct |
1639 ms |
344 KB |
Output is correct (P=0.2, F=731.4, Q=760.7) -> 77.57 points |
