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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#528616#9162. COVID testsDimash#0 0ms0kbC++233.5kb2024-08-23 16:58:142024-08-23 16:58:14

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你现在查看的是最新测评结果

  • [2024-08-23 16:58:14]
  • 评测
  • 测评结果:0
  • 用时:0ms
  • 内存:0kb
  • [2024-08-23 16:58:14]
  • 提交

answer

#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 = 1;
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)>go = [&](int l,int r) {
        if(l > r) return;
        if(l == r) {
            answer[l] = 1;
            return;
        }
        int mid = (l + r) >> 1;
        if(as(l,mid)) {
            go(l,mid);
        }
        if(as(mid+1,r)) {
            go(mid+1,r);
        }
    };
    function<void(int,int,int)>solve = [&](int l,int r,int b){
        int i = l;
        while(i < r) {
            int r = min(N - 1,i + b);
            if(as(i,r)) {
                // cout << i << ' ' << r << '\n';
                if(b == 31) {
                    solve(i,r,7);
                } else {
                    go(i,r);
                }
            }
            i = r + 1;
        }
    };
    if(P > 0.011546){
        solve(0,N-1,31);
    } 
    else {
        int i = 0;
        while(i < N) {
            int l = i - 1,r = N;
            while(r - l > 1) {
                int mid = (l + r) >> 1;
                if(as(i,mid)) {
                    r = mid;
                } else {
                    l = mid;
                }
            }
            if(r < N) {
                answer[r] = 1;
                i = r + 1;
            } else {
                break;
            }
        }
    }
    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;
}

Details

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Subtask #1:

score: 0
Time Limit Exceeded

Test #1:

score: 0
Time Limit Exceeded

input:

1000 0.789673 1

output:


result:


Subtask #2:

score: 0
Time Limit Exceeded

Test #18:

score: 0
Time Limit Exceeded

input:

1000 0.001 300

output:


result: