Submission #554142

#	Time	Username	Problem	Language	Result	Execution time	Memory
554142		alontanay	A Difficult(y) Choice (BOI21_books)	C++14	100 / 100	2 ms	336 KiB

books

#include <bits/stdc++.h>
#include "books.h"
#define ll long long

using namespace std;

ll qry[100005];

ll get(int i) {
    if(qry[i]) { return qry[i]; }
    return qry[i] = skim(i);
}

void solve(int N, int K, long long A, int S) {
    ll pre = 0;
    for(int i = 1; i < K; i ++) {
        pre += get(i);
    }
    get(K);
    int l = 1, r = N;
    while(l<r) {
        int mid = (l+r)/2;
        if(get(mid) < A) {
            l = mid + 1;
        } else {
            r = mid;
        }
    }
    if(l >= K) {
        if(get(l) + pre >= A && get(l) + pre <= 2 * A) {
            vector<int> res = {l};
            for(int i = 1; i < K; i ++) {
                res.push_back(i);
            }
            answer(res);
            return;
        }
    } else {
        impossible();
        return;
    }
    if(get(l) > A) {
        l --;
    }
    pre += get(K);
    ll suf = 0;
    for(int i = l; i > l - K; i --) {
        suf += get(i);
    }
    if(pre > 2 * A) {
        impossible();
        return;
    }
    if(suf < A) {
        impossible();
        return;
    }
    vector<int> res(K);
    for(int i = 0; i < K; i ++) {
        res[i] = i + 1;
    }
    int idx = 0;
    while(pre < A) {
        res[idx] = l - idx;
        pre -= get(idx+1);
        pre += get(l-idx);
        idx ++;
    }
    answer(res);
    return;
}

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