Submission #1316574

#	Time	Username	Problem	Language	Result	Execution time	Memory
1316574		lucas110550	Festival (IOI25_festival)	C++20	48 / 100	68 ms	33056 KiB

festival

#include <bits/stdc++.h>
using namespace std;

// A is int, P is vector<int>, T is vector<int>
// Return chosen coupon original indices (0-based), matching the Python logic/order.
vector<int> max_coupons(int A, vector<int> P, vector<int> T) {
    int n = (int)P.size();

    // ---------- split coupons ----------
    vector<pair<long long,int>> cheap; // (price, original_index) for T==1

    struct Booster {
        long long key; // price * coeff[t]
        long long p;   // price
        int t;
        int idx;       // original index
    };
    vector<Booster> boosters;

    // coeff = 12*T/(T-1) for T in {2,3,4} -> {24,18,16}
    long long coeff[5] = {0, 0, 24, 18, 16};

    for (int i = 0; i < n; i++) {
        int ti = T[i];
        long long pi = (long long)P[i];
        if (ti == 1) {
            cheap.push_back({pi, i});
        } else {
            long long key = pi * coeff[ti];
            boosters.push_back({key, pi, ti, i});
        }
    }

    // ---------- sort ----------
    sort(cheap.begin(), cheap.end(),
         [](const auto& a, const auto& b) { return a.first < b.first; });

    sort(boosters.begin(), boosters.end(),
         [](const Booster& a, const Booster& b) {
             if (a.key != b.key) return a.key < b.key;
             return a.p < b.p;
         });

    vector<long long> cheap_psum;
    vector<int> cheap_idx;
    cheap_psum.reserve(cheap.size() + 1);
    cheap_idx.reserve(cheap.size());
    cheap_psum.push_back(0);

    for (auto &cp : cheap) {
        cheap_psum.push_back(cheap_psum.back() + cp.first);
        cheap_idx.push_back(cp.second);
    }

    auto bisect_right = [&](const vector<long long>& arr, long long x) -> int {
        return (int)(upper_bound(arr.begin(), arr.end(), x) - arr.begin());
    };

    // ---------- take all non-decreasing boosters ----------
    long long token = (long long)A;
    vector<int> prefix_ids;
    int i = 0, m = (int)boosters.size();

    while (i < m) {
        const auto& b = boosters[i];
        long long p = b.p;
        int t = b.t;

        // Python: token * (t - 1) >= p * t
        __int128 L = (__int128)token * (t - 1);
        __int128 R = (__int128)p * t;

        if (L >= R) {
            prefix_ids.push_back(b.idx);
            token = (token - p) * (long long)t;
            i++;
        } else {
            break;
        }
    }

    // ---------- hard suffix ----------
    vector<Booster> hard(boosters.begin() + i, boosters.end());
    int h_len = (int)hard.size();

    const int K = 61;
    vector<long long> dp(K + 1, -1);
    dp[0] = token;

    vector<vector<uint8_t>> parent(h_len, vector<uint8_t>(K + 1, 0));

    for (int j = 0; j < h_len; j++) {
        long long p = hard[j].p;
        int t = hard[j].t;
        int max_c = min(j + 1, K);

        for (int c = max_c; c >= 1; c--) {
            long long prev = dp[c - 1];
            if (prev >= p) {
                long long cand = (prev - p) * (long long)t;
                if (cand > dp[c]) {
                    dp[c] = cand;
                    parent[j][c] = 1;
                }
            }
        }
    }

    // ---------- evaluate all possibilities ----------
    int best_total = -1;
    int best_c = 0;
    long long best_token = dp[0];

    for (int c = 0; c <= min(K, h_len); c++) {
        long long cur = dp[c];
        if (cur < 0) continue;

        int cheap_cnt = bisect_right(cheap_psum, cur) - 1;
        int total = i + c + cheap_cnt;
        if (total > best_total) {
            best_total = total;
            best_c = c;
            best_token = cur;
        }
    }

    // ---------- reconstruct the chosen hard subset ----------
    vector<int> chosen_hard;
    int need = best_c;

    for (int j = h_len - 1; j >= 0; j--) {
        if (need == 0) break;
        if (parent[j][need]) {
            chosen_hard.push_back(j);
            need--;
        }
    }
    reverse(chosen_hard.begin(), chosen_hard.end());

    // ---------- build final answer ----------
    vector<int> answer;
    answer.insert(answer.end(), prefix_ids.begin(), prefix_ids.end());

    token = best_token; // as in Python, no need to recompute
    for (int j : chosen_hard) {
        answer.push_back(hard[j].idx);
    }

    int cheap_cnt_final = bisect_right(cheap_psum, token) - 1;
    for (int k = 0; k < cheap_cnt_final; k++) {
        answer.push_back(cheap_idx[k]);
    }

    return answer;
}

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 12
• Subtask 4: 0 / 15
• Subtask 5: 27 / 27
• Subtask 6: 16 / 16
• Subtask 7: 0 / 18