Submission #1238147

#	Time	Username	Problem	Language	Result	Execution time	Memory
1238147		SalihSahin	Carnival Tickets (IOI20_tickets)	C++20	27 / 100	330 ms	86792 KiB

tickets

#include "bits/stdc++.h"
#include "tickets.h"
#define pb push_back
using namespace std;

const long long inf = 1e15;

long long find_maximum(int k, vector<vector<int>> x) {
    int n = x.size();
    int m = x[0].size();
    vector<vector<int>> ans(n, vector<int>(m, -1));

    if(m == 1){
        long long val = 0;
        vector<int> arr;
        for(int i = 0; i < n; i++){
            arr.pb(x[i][0]);
            val += x[i][0];

            ans[i][0] = 0;
        }
        sort(arr.begin(), arr.end());
        for(int i = 0; i < n/2; i++){
            val -= arr[i] * 2;
        }

        allocate_tickets(ans);
        return val;
    }
    else if(k == 1){
        vector<int> mini(n), maxi(n);
        for(int i = 0; i < n; i++){
            for(int j = 0; j < m; j++){
                if(x[i][j] > x[i][maxi[i]]){
                    maxi[i] = j;
                }
                if(x[i][j] < x[i][mini[i]]){
                    mini[i] = j;
                }
            }
        }

        vector<vector<long long> > dp(n+1, vector<long long>(n/2+2, -inf));
        vector<vector<pair<long long, long long> > > par(n+1, vector<pair<long long, long long> >(n/2+2));
        dp[0][0] = 0;
        for(int i = 0; i < n; i++){
            for(int j = 0; j <= min(i, n/2); j++){
                if(dp[i][j] + x[i][maxi[i]] > dp[i+1][j+1]){
                    dp[i+1][j+1] = dp[i][j] + x[i][maxi[i]];
                    par[i+1][j+1] = {i, j};
                }
                if(dp[i][j] - x[i][mini[i]] > dp[i+1][j]){
                    dp[i+1][j] = dp[i][j] - x[i][mini[i]];
                    par[i+1][j] = {i, j};
                }
            }
        }

        vector<vector<int> > ans(n, vector<int>(m, -1));
        pair<int, int> now = {n, n/2};
        while(now != make_pair(0, 0)){
            pair<int, int> nxt = par[now.first][now.second];
            if(now.second == nxt.second){
                ans[nxt.first][mini[nxt.first]] = 0;
            }
            else{
                ans[nxt.first][maxi[nxt.first]] = 0;
            }
            now = nxt;
        }

        allocate_tickets(ans);
        return dp[n][n/2];
    }

    return 0;
}

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