Submission #810803

#	Time	Username	Problem	Language	Result	Execution time	Memory
810803		laurasofia	A Difficult(y) Choice (BOI21_books)	C++14	0 / 100	1 ms	208 KiB

books

#include <bits/stdc++.h>

#include "books.h"


#define FOR(i,a,b) for(int i=a;i<b;i++)
#define lli long long int
#define vv vector<lli>
#define pr pair<int,int>
#define print(a) cout<<a<<endl
#define f first
#define s second


using namespace std;
//
// --- Sample implementation for the task books ---
//
// To compile this program with the sample grader, place:
//     books.h books_sample.cpp sample_grader.cpp
// in a single folder and run:
//     g++ books_sample.cpp sample_grader.cpp
// in this folder.
//

bool check(lli sum, lli A){
    return  (sum>=A && sum<=2*A);
}

void solve(int N, int K, long long A, int S) {

    vector<int> res;
    vv one;
    lli sum=0;
    FOR(i,0,K){
        one.push_back(skim(i+1));
        sum+=one[i];
    }
    if (sum>=A && sum<=2*A){
        
        FOR(i,1,K+1)res.push_back(i);
        answer(res);return;
    }
    if (sum>2*A){
        impossible();return;
    }
    int l=1;
    int r=N;
    long long a;
    while(l+1<r){
        int m=(l+r)>>1;
        a=skim(m);

        if (A<a)r=m;
        else l=m;
    }
    if (skim(l)>=A)r=l;
    a=skim(r);

    if (r<K){
        impossible();
        return;
    }
    
    if (check(sum+a-one.back(),A)){

        FOR(i,1,K+1)res.push_back(i);
        res[K-1]=r;
        answer(res);return;
    }

    vv two;
    sum=0;
    FOR(i,r-K,r){
        lli a=skim(i);
        two.push_back(a);
        sum+=a;
    }
    if (sum>=A && sum<=2*A){

        FOR(i,r-K,r)res.push_back(i);
        answer(res);return;
    }

    FOR(i,1,K+1)res.push_back(i);
    FOR(i,0,K){
        res[i]=r-K+i;
        sum+=two[i]-one[i];
        if (check(sum,A)){
            answer(res);return;
        }
    }
    impossible();


}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 15
• Subtask 3: 0 / 10
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20