oj.uz

Submission #1073539

# Submission time Handle Problem Language Result Execution time Memory
1073539 2024-08-24T15:50:28 Z ProtonDecay314 COVID tests (CEOI24_covid) C++17
36.95 / 100
 2580 ms 596 KB 
// AM + DG
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<ll, ll> pll;
typedef vector<pll> vpll;
typedef pair<int, int> pi;
typedef vector<pi> vpi;
typedef vector<bool> vb;
#define fi first
#define se second
#define IOS cin.tie(nullptr); cout.tie(nullptr); ios_base::sync_with_stdio(false)
#define pb push_back
#define INF(dtype) numeric_limits<dtype>::max()
#define NINF(dtype) numeric_limits<dtype>::min()

/// You may use:

// The number of students
int N;

// The probability any given student is positive
double P;

// The size of the set that maximizes entropy/"surprise"
// ! later

// 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& answer) {
    vb mask(N, false);
    
    for(int i = l; i <= r; i++) mask[i] = true;
    bool res = test_students(mask);

    if(!res) {
        for(int i = l; i <= r; i++) answer[i] = false;
    } else if(l == r) {
        answer[l] = true;
    } else {
        int m = (l + r) >> 1;
        solve(l, m, answer);
        solve(m + 1, r, answer);
    }
}

std::vector<bool> find_positive() {
    std::vector<bool> answer(N);

    solve(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;
}

Compilation message

Main.cpp: In function 'bool test_students(std::vector<bool>)':
Main.cpp:47:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |     scanf(" %c", &answer);
      |     ~~~~~^~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:85:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |     scanf("%d %lf %d", &N, &P, &T);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:101:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  101 |         scanf(" %c", &verdict);
      |         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 344 KB Output is correct
2 Correct 12 ms 340 KB Output is correct
3 Correct 12 ms 344 KB Output is correct
4 Correct 10 ms 344 KB Output is correct
5 Correct 12 ms 344 KB Output is correct
6 Correct 11 ms 344 KB Output is correct
7 Correct 9 ms 344 KB Output is correct
8 Correct 9 ms 344 KB Output is correct
9 Correct 11 ms 344 KB Output is correct
10 Correct 7 ms 344 KB Output is correct
11 Correct 9 ms 344 KB Output is correct
12 Correct 10 ms 344 KB Output is correct
13 Correct 10 ms 344 KB Output is correct
14 Correct 13 ms 344 KB Output is correct
15 Correct 9 ms 344 KB Output is correct
16 Correct 12 ms 344 KB Output is correct
17 Correct 1 ms 344 KB Output is correct

Subtask #2
26.949999996 / 90.0

# Verdict Execution time Memory Grader output
1 Correct 43 ms 344 KB Output is correct (P=0.001, F=15.1, Q=17.8) -> 52.47 points
2 Correct 180 ms 344 KB Output is correct (P=0.005256, F=51.1, Q=78.0) -> 28.98 points
3 Correct 378 ms 344 KB Output is correct (P=0.011546, F=94.9, Q=150.0) -> 27.09 points
4 Correct 745 ms 344 KB Output is correct (P=0.028545, F=191.5, Q=303.5) -> 26.95 points
5 Correct 920 ms 344 KB Output is correct (P=0.039856, F=246.3, Q=388.5) -> 27.20 points
6 Correct 1376 ms 596 KB Output is correct (P=0.068648, F=366.2, Q=569.4) -> 27.95 points
7 Correct 1795 ms 344 KB Output is correct (P=0.104571, F=490.3, Q=751.4) -> 28.75 points
8 Correct 2216 ms 344 KB Output is correct (P=0.158765, F=639.1, Q=967.6) -> 29.45 points
9 Correct 2580 ms 344 KB Output is correct (P=0.2, F=731.4, Q=1112.6) -> 29.18 points