Submission #1076831

# Submission time Handle Problem Language Result Execution time Memory
1076831 2024-08-26T17:01:47 Z oscar1f COVID tests (CEOI24_covid) C++17
39.35 / 100
2684 ms 956 KB
#include<bits/stdc++.h>
#include <cassert>
#include <cstdio>
#include <string>
#include <vector>
using namespace std;

/// You may use:

// The number of students
const int TAILLE_MAX=1000+5;
const double INFINI=1000.0*1000.0*1000.0;
int N,nbTest;
vector<bool> rep;
vector<bool> attendu;
double puis[TAILLE_MAX];
double memo[TAILLE_MAX];
int suiv[TAILLE_MAX];

// 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(vector<bool> mask) {
    assert(mask.size() == (size_t)N);

    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';
}

/*bool test_students(vector<bool> mask) {
    nbTest++;
    bool ans=false;
    for (int i=0;i<N;i++) {
        if (mask[i] and attendu[i]) {
            ans=true;
        }
    }
    return ans;
}*/

bool dicho(int deb,int fin,bool assure) {
    bool ans;
    if (!assure) {
        vector<bool> quest;
        for (int i=0;i<N;i++) {
            if (i>=deb and i<=fin) {
                quest.push_back(true);
            }
            else {
                quest.push_back(false);
            }
        }
        ans=test_students(quest);
    }
    else {
        ans=true;
    }
    if (ans) {
        int taille=fin-deb+1;
        if (taille==1) {
            rep[deb]=true; 
        }
        else {
            int mid=deb+suiv[taille]-1;
            if (dicho(deb,mid,false)) {
                dicho(mid+1,fin,false);
            }
            else {
                dicho(mid+1,fin,true);
            }
        }

    }
    return ans;
}

/// 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.
vector<bool> find_positive() {
    vector<bool> quest(N,true);
    rep.clear();
    rep.resize(N,false);
    dicho(0,N-1,false);
    return rep;
}

void init() {
    puis[0]=1.0;
    for (int i=1;i<=N;i++) {
        puis[i]=puis[i-1]*(1.0-P);
        //cout<<puis[i]<<" ";
    }
    //cout<<endl;
    memo[0]=0.0;
    memo[1]=0.0;
    double esper;
    for (int i=2;i<=N;i++) {
        memo[i]=INFINI;
        for (int j=1;j<i;j++) {
            esper=1.0+max(1.0-puis[j],1.6*(double)j/(double)i)*(memo[j])+memo[i-j];
            if (esper<memo[i]) {
                memo[i]=esper;
                suiv[i]=j;
            }
        }
        //cout<<i<<" : "<<suiv[i]<<" "<<memo[i]<<endl;
    }
    //cout<<suiv[1000]<<" "<<memo[1000]<<endl;
}

int main() {
    int T;
    scanf("%d %lf %d", &N, &P, &T);
    init();
    // 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;
}

/*int main() {
    int T;
    cin>>N>>P>>T;
    init();
    // You may perform any extra initialization here.
    char val;
    for (int i = 0; i < T; i++) {
        attendu.clear();
        for (int j=0;j<N;j++) {
            cin>>val;
            //cout<<val;
            attendu.push_back(val=='1');
        }
        std::vector<bool> answer = find_positive();
        for (int j=0;j<N;j++) {
            if (attendu[j]!=answer[j]) {
                cout<<"PROBLEME"<<" "<<i<<" "<<j<<endl;
                return 0;
            }
        }
    }
    cout<<nbTest/T<<endl;
    cout<<"OK"<<endl;
    return 0;
}*/

Compilation message

Main.cpp: In function 'bool test_students(std::vector<bool>)':
Main.cpp:38:10: 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:129:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  129 |     scanf("%d %lf %d", &N, &P, &T);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:145:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  145 |         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 23 ms 852 KB Output is correct
2 Correct 17 ms 720 KB Output is correct
3 Correct 24 ms 956 KB Output is correct
4 Correct 27 ms 948 KB Output is correct
5 Correct 23 ms 600 KB Output is correct
6 Correct 22 ms 488 KB Output is correct
7 Correct 15 ms 500 KB Output is correct
8 Correct 14 ms 600 KB Output is correct
9 Correct 22 ms 740 KB Output is correct
10 Correct 7 ms 344 KB Output is correct
11 Correct 11 ms 600 KB Output is correct
12 Correct 12 ms 344 KB Output is correct
13 Correct 14 ms 600 KB Output is correct
14 Correct 14 ms 500 KB Output is correct
15 Correct 15 ms 744 KB Output is correct
16 Correct 20 ms 596 KB Output is correct
17 Correct 2 ms 344 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 73 ms 344 KB Output is correct (P=0.001, F=15.1, Q=19.5) -> 41.56 points
2 Correct 234 ms 344 KB Output is correct (P=0.005256, F=51.1, Q=77.5) -> 29.35 points
3 Correct 441 ms 600 KB Output is correct (P=0.011546, F=94.9, Q=142.5) -> 29.94 points
4 Correct 781 ms 344 KB Output is correct (P=0.028545, F=191.5, Q=270.5) -> 33.96 points
5 Correct 1034 ms 596 KB Output is correct (P=0.039856, F=246.3, Q=346.5) -> 34.26 points
6 Correct 1443 ms 344 KB Output is correct (P=0.068648, F=366.2, Q=468.5) -> 42.50 points
7 Correct 1819 ms 600 KB Output is correct (P=0.104571, F=490.3, Q=629.0) -> 42.22 points
8 Correct 2375 ms 344 KB Output is correct (P=0.158765, F=639.1, Q=793.2) -> 45.81 points
9 Correct 2684 ms 344 KB Output is correct (P=0.2, F=731.4, Q=911.7) -> 45.32 points