Submission #414052

#	Time	Username	Problem	Language	Result	Execution time	Memory
414052		Tc14	A Difficult(y) Choice (BOI21_books)	C++17	60 / 100	2 ms	292 KiB

books

//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#include "books.h"
using namespace std;
#define ve vector
typedef long long ll;
typedef pair<int, int> pii;
const int INF = 1e9 + 10;

map<int, ll> M;

ll B(int i) {
    if (M.find(i) == M.end()) M[i] = skim(i + 1);
    return M[i];
}

void solve(int n, int k, ll a, int s) {

    int lo = 0;
    int hi = n - 1;

    while (lo < hi) {

        int m = (lo + hi) / 2;

        if (B(m) >= a) hi = m;
        else lo = m + 1;
    }

    int z = lo;
    ll x = B(z);

    if (x >= a) {
        if (z >= k - 1) {
            ll sum = x;
            ve<int> I(k);
            I[k - 1] = z + 1;
            for (int i = 0; i < k - 1; i++) {
                sum += B(i);
                I[i] = i + 1;
            }
            if (sum <= 2 * a) {
                answer(I);
                return;
            }
        }
    }
    else z = n;

    if (z >= k) {

        ll sum = 0;
        ve<int> I(k);
        for (int i = 0; i < k; i++) {
            sum += B(i);
            I[i] = i + 1;
        }

        for (int i = k - 1; i >= 0; i--) {
            hi = z - k + i;
            lo = i;

            sum -= B(i);
            if (sum + B(hi) >= a) {

                while (lo < hi) {

                    int m = (lo + hi) / 2;

                    if (sum + B(m) < a) lo = m + 1;
                    else if (sum + B(m) > 2 * a) hi = m;
                    else {
                        I[i] = m + 1;
                        answer(I);
                        return;
                    }

                }

                if (a <= sum + B(lo) && sum + B(lo) <= 2 * a) {
                    I[i] = lo + 1;
                    answer(I);
                    return;
                }

            }
            else {
                sum += B(hi);
                I[i] = hi + 1;
            }
        }
    }

    impossible();
}

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