oj.uz

Submission #1061450

# Submission time Handle Problem Language Result Execution time Memory
1061450 2024-08-16T09:09:54 Z Dan4Life COVID tests (CEOI24_covid) C++17
100 / 100
 1735 ms 596 KB 
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) begin(a), end(a)
using ll = long long;
using vi = vector<int>;
using ar2 = array<int,2>;
using ar3 = array<int,3>;
using ar4 = array<int,4>;
const int INF = (int)2e9;
const int mxN = (int)1e6+10;
int N;
double P;
 
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');
}

bool test(int l, int r){
    vector<bool> testt(N,0);
    for(int i = l; i <= r; i++) testt[i]=1;
    return test_students(testt);
}
 
vector<bool> find_positive() {
    vector<bool> answer(N,0);
    if(!P) return answer;
    if(P>=0.3){
        for(int i = 0; i < N; i++)
            answer[i]=test(i,i);
        return answer;
    } 
    int B = 0; double prob = 1.0-P;
    while(prob>=0.5) prob*=(1.0-P), B++;
    if(P>0.16) B=3;
    else if(P>0.1 and P<0.15) B=7;
    for(int i = 0; i < N; i+=B){
        int rr = min(N,i+B)-1;
        while(i<=rr and test(i,rr)){
            int l = i, r = rr;
            while(l<r){
                int mid = (l+r-1)/2;
                if(test(l,mid)) r=mid;
                else l=mid+1;
            }
            answer[l]=1; i=l+1,rr=min(N-1,l+B);
        }
    }
    return answer;
}
 
int main() {
    int T;
    scanf("%d %lf %d", &N, &P, &T);
 
    for (int i = 0; i < T; i++) {
        vector<bool> answer = find_positive();
        assert(answer.size() == (size_t)N);
 
        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:26:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |     scanf(" %c", &answer);
      |     ~~~~~^~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:65:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     scanf("%d %lf %d", &N, &P, &T);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:79:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |         scanf(" %c", &verdict);
      |         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 344 KB Output is correct
2 Correct 6 ms 344 KB Output is correct
3 Correct 6 ms 344 KB Output is correct
4 Correct 7 ms 344 KB Output is correct
5 Correct 8 ms 344 KB Output is correct
6 Correct 6 ms 344 KB Output is correct
7 Correct 5 ms 344 KB Output is correct
8 Correct 6 ms 344 KB Output is correct
9 Correct 7 ms 596 KB Output is correct
10 Correct 4 ms 344 KB Output is correct
11 Correct 6 ms 344 KB Output is correct
12 Correct 6 ms 344 KB Output is correct
13 Correct 5 ms 344 KB Output is correct
14 Correct 6 ms 344 KB Output is correct
15 Correct 6 ms 344 KB Output is correct
16 Correct 6 ms 344 KB Output is correct
17 Correct 0 ms 344 KB Output is correct

Subtask #2
90.0 / 90.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 344 KB Output is correct (P=0.001, F=15.1, Q=10.9) -> 90.00 points
2 Correct 102 ms 344 KB Output is correct (P=0.005256, F=51.1, Q=46.5) -> 90.00 points
3 Correct 218 ms 344 KB Output is correct (P=0.011546, F=94.9, Q=90.9) -> 90.00 points
4 Correct 459 ms 344 KB Output is correct (P=0.028545, F=191.5, Q=189.3) -> 90.00 points
5 Correct 591 ms 344 KB Output is correct (P=0.039856, F=246.3, Q=243.9) -> 90.00 points
6 Correct 874 ms 344 KB Output is correct (P=0.068648, F=366.2, Q=364.6) -> 90.00 points
7 Correct 1115 ms 344 KB Output is correct (P=0.104571, F=490.3, Q=489.2) -> 90.00 points
8 Correct 1353 ms 344 KB Output is correct (P=0.158765, F=639.1, Q=633.1) -> 90.00 points
9 Correct 1735 ms 344 KB Output is correct (P=0.2, F=731.4, Q=729.4) -> 90.00 points