Submission #928092

#	Time	Username	Problem	Language	Result	Execution time	Memory
928092		EJIC_B_KEDAX	Carnival Tickets (IOI20_tickets)	C++17	11 / 100	1 ms	860 KiB

tickets

#include <bits/stdc++.h>
#include "tickets.h"

using ll = long long;

using namespace std;

ll find_maximum(int k, vector<vector<int>> t) {
    int n = t.size(), m = t[0].size();
    vector<int> all;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            all.push_back(t[i][j]);
        }
    }
    sort(all.begin(), all.end());
    int middle = all[all.size() / 2];
    ll res = 0;
    vector<pair<ll, int>> a(n);
    vector<int> bg(n, 0), end(n, m - 1);
    vector<vector<int>> s(n, vector<int>(m, -1));
    for (int i = 0; i < n; i++) {
        a[i].first = 0;
        a[i].second = i;
        for (int j = 0; j < m; j++) {
            t[i][j] -= middle;
        }
    }
    for (int st = 0; st < k; st++) {
        vector<pair<int, int>> l, r;
        for (int i = 0; i < n; i++) {
            if (abs(t[i][bg[i]]) > abs(t[i][end[i]])) {
                if (t[i][end[i]] < 0) {
                    l.emplace_back(INT32_MAX, i);
                } else {
                    l.emplace_back(abs(abs(t[i][bg[i]]) - abs(t[i][end[i]])), i);
                }
            } else {
                if (t[i][bg[i]] > 0) {
                    l.emplace_back(INT32_MAX, i);
                } else {
                    l.emplace_back(abs(abs(t[i][bg[i]]) - abs(t[i][end[i]])), i);
                }
            }
        }
        sort(l.begin(), l.end(), greater<>());
        sort(r.begin(), r.end(), greater<>());
        set<int> li, ri;
        for  (auto [w, i] : l) {
            li.insert(i);
        }
        for  (auto [w, i] : r) {
            ri.insert(i);
        }
        while (l.size() > n / 2) {
            li.erase(l.back().second);
            ri.insert(l.back().second);
            l.pop_back();
        }
        while (r.size() > n / 2) {
            ri.erase(r.back().second);
            li.insert(r.back().second);
            r.pop_back();
        }
        vector<int> nw;
        for (int i : li) {
            s[i][bg[i]] = st;
            nw.push_back(t[i][bg[i]++]);
        }
        for (int i : ri) {
            s[i][end[i]] = st;
            nw.push_back(t[i][end[i]--]);
        }
        sort(nw.begin(), nw.end());
        for (int i : nw) {
            res += abs(i);
        }
        assert(0 >= nw[n / 2 - 1] && 0 <= nw[n / 2]);
    }
    allocate_tickets(s);
    return res;
}

Compilation message (stderr)

tickets.cpp: In function 'll find_maximum(int, std::vector<std::vector<int> >)':
tickets.cpp:55:25: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   55 |         while (l.size() > n / 2) {
      |                ~~~~~~~~~^~~~~~~
tickets.cpp:60:25: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   60 |         while (r.size() > n / 2) {
      |                ~~~~~~~~~^~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 0 / 16
• Subtask 3: 0 / 14
• Subtask 4: 0 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23
• Subtask 7: 0 / 10