Submission #303438

#	Time	Username	Problem	Language	Result	Execution time	Memory
303438		baluteshih	Carnival Tickets (IOI20_tickets)	C++14	62 / 100	2079 ms	2097156 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
#define X first
#define Y second
#define ALL(v) v.begin(),v.end()
#define SZ(a) ((int)a.size())
#define pb push_back

const ll INF=1e18;

ll find_maximum(int k, vector<vector<int>> x)
{
	int n = x.size();
	int m = x[0].size();
    int tar=n*k/2;
    vector<vector<ll>> dp(n+1,vector<ll>(tar+1,-INF)),take(n+1,vector<ll>(k+1,0));
    vector<vector<int>> answer(n,vector<int>(m,-1));
    vector<int> cnt(n,0),num(n,0),nw(n,0),tp(n,0);
    for(int i=1;i<=n;++i)
    {
        for(int j=0;j<k;++j)
            take[i][0]-=x[i-1][j];
        for(int j=1;j<=k;++j)
            take[i][j]=take[i][j-1]+x[i-1][k-j]+x[i-1][m-j];
    }
    dp[0][tar]=0;
    for(int i=1;i<=n;++i)
        for(int j=0,t=k;j<=tar;++j)
        {
            while(t>0&&(j+t>tar||dp[i-1][j+t]+take[i][t]<=dp[i-1][j+t-1]+take[i][t-1]))
                --t;
            dp[i][j]=dp[i-1][j+t]+take[i][t];
            //for(int t=0;t<=k&&j+t<=tar;++t)
            //    dp[i][j]=max(dp[i][j],dp[i-1][j+t]+take[i][t]);
        }
    int nxt=0;
    /*for(int i=1;i<=n;++i)
        for(int j=0;j<=tar;++j)
        {
            int frm=0;
            for(int t=0;t<=k&&j+t<=tar;++t)
                if(dp[i][j]==dp[i-1][j+t]+take[i][t])
                {
                    frm=t;
                    break;
                }
            cout << frm << " \n"[j==tar];
        }*/
    for(int i=n;i>=1;--i)
    {
        for(int t=0;t<=k;++t)
            if(dp[i][nxt]==dp[i-1][nxt+t]+take[i][t])
            {
                cnt[i-1]=t;
                nxt+=t;
                break;
            }
    }
    for(int i=0;i<n;++i)
        nw[i]=k-cnt[i],num[i]=i,tp[i]=cnt[i];
    for(int i=0;i<k;++i)
    {
        sort(ALL(num),[&](int a,int b){return cnt[a]>cnt[b];});
        for(int j=0;j<n/2;++j)
            answer[num[j]][m-tp[num[j]]+(--cnt[num[j]])]=i;
        for(int j=n/2;j<n;++j)
            answer[num[j]][--nw[num[j]]]=i;
    }
    allocate_tickets(answer);
	return dp[n][0];
}

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