Submission #635138

#	Time	Username	Problem	Language	Result	Execution time	Memory
635138		stevancv	Carnival Tickets (IOI20_tickets)	C++14	100 / 100	637 ms	54340 KiB

tickets

#include <bits/stdc++.h>
#include "tickets.h"
#define ll long long
#define ld long double
#define sp ' '
#define en '\n'
#define smin(a, b) a = min(a, b)
#define smax(a, b) a = max(a, b)
using namespace std;
const int N = 5e5 + 2;
const int mod = 1e9 + 7;
ll find_maximum(int k, vector<vector<int>> a) {
    int n = a.size(); int m = a[0].size();
    vector<int> l(n, k - 1), r(n, m - 1);
    priority_queue<array<int, 2>> pq;
    for (int i = 0; i < n; i++) pq.push({a[i][l[i]] + a[i][r[i]], i});
    int uk = n * k / 2;
    while (uk--) {
        int i = pq.top()[1]; pq.pop();
        l[i]--; r[i]--;
        if (l[i] >= 0) pq.push({a[i][l[i]] + a[i][r[i]], i});
    }
    vector<int> kol(n);
    ll sol = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j <= l[i]; j++) sol -= a[i][j];
        for (int j = r[i] + 1; j < m; j++) sol += a[i][j];
        kol[i] = k - l[i] - 1;
        l[i] = 0; r[i] = m - 1;
    }
    vector<vector<int>> ans(n, vector<int>(m, -1));
    for (int z = 0; z < k; z++) {
        vector<int> id(n);
        iota(id.begin(), id.end(), 0);
        sort(id.begin(), id.end(), [&] (int i, int j) {
            return kol[i] < kol[j];
        });
        for (int i = 0; i < n / 2; i++) {
            ans[id[i]][l[id[i]]] = z;
            l[id[i]]++;
        }
        for (int i = n / 2; i < n; i++) {
            ans[id[i]][r[id[i]]] = z;
            r[id[i]]--;
            kol[id[i]]--;
        }
    }
    allocate_tickets(ans);
    return sol;
}

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