Submission #1250770

#	Time	Username	Problem	Language	Result	Execution time	Memory
1250770		starnightsnow	Souvenirs (IOI25_souvenirs)	C++20	22 / 100	3 ms	412 KiB

souvenirs

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

extern pair<vector<int>, long long> transaction(long long M);

void buy_souvenirs(int N, long long P0) {
    long long expless1 = P0 - 1;
    if (N == 2) {
        auto [gotten, change] = transaction(expless1);
        return;
    }
    if(N == 3){
        auto [gotten1, change1] = transaction(expless1);
        ll use;
        if(gotten1.size() == 1){
            use = (expless1) - change1 - 1;
            auto [gotten2, change2] = transaction(use);
            auto [gotten3, change3] = transaction(use);
        }
        else{
            use = (expless1 - change1 - 1) / 2;
            auto [gotten2, change2] = transaction(use);
        }
        return;
    }

    vector<ll> prices(N, -1);
    prices[0] = P0;
    vector<int> bought(N, 0); 

    set<int> need;
    for (int i = 1; i < N; ++i)
        need.insert(i);

    while (!need.empty()) {
        bool done = false;

        for (int idx : need) {
            ll low = 1, high = P0 - 1;
            while (low <= high) {
                ll mid = (low + high) / 2;
                auto [gotten, change] = transaction(mid);
                ll sum = mid - change;

                for (int g : gotten)
                    bought[g]++;

                if (gotten.size() == 1 && gotten[0] == idx) {
                    prices[idx] = sum;
                    need.erase(idx);
                    done = true;
                    break;
                }

                if (bought[idx] >= idx) {
                    need.erase(idx);
                    done = true;
                    break;
                }

                if (find(gotten.begin(), gotten.end(), idx) == gotten.end()) {
                    low = mid + 1;
                } else {
                    high = mid - 1;
                }
            }

            if (done)
                break;
        }

        if (!done)
            break;
    }


    for (int i = 1; i < N; ++i) {
        while (bought[i] < i) {
            auto [gotten, change] = transaction(prices[i]);
            for (int item : gotten)
                bought[item]++;
        }
    }

}

• Subtask 0: 0 / 0
• Subtask 1: 4 / 4
• Subtask 2: 0 / 3
• Subtask 3: 0 / 14
• Subtask 4: 18 / 18
• Subtask 5: 0 / 28
• Subtask 6: 0 / 33