Submission #1047231

#	Time	Username	Problem	Language	Result	Execution time	Memory
1047231		idas	Carnival Tickets (IOI20_tickets)	C++17	11 / 100	4 ms	860 KiB

tickets

#include "tickets.h"
#include "bits/stdc++.h"
#define FOR(i, begin, end) for(int i=(begin); i<(end); i++)
#define sz(x) ((int)((x).size()))

using namespace std;
typedef long long ll;
typedef vector<int> vi;

const int MxN=1510, INF=1e9;
int n, m, in[MxN], ix[MxN];

long long find_maximum(int k, std::vector<std::vector<int>> x) {
    n=sz(x); m=sz(x[0]);

    FOR(i, 0, n) ix[i]=m-1;

    ll ret=0;
    vector<vector<int>> s(n, vector<int>(m,-1));
    FOR(r, 0, k) {
        vi now;
        vector<bool> v(n, false);
        FOR(z, 0, n/2) {
            int mx[2]={-1,-1}, mxi[2]={0,0}, mn[2]={INF+1,INF+1}, mni[2]={0,0};
            FOR(i, 0, n) {
                // if(in[i]>=sz(x[i])) continue;
                if(v[i]) continue;
                // assert(in[i]<sz(x[i]));
                // assert(!x[i].empty());
                if(x[i][ix[i]]>mx[0]) {
                    mx[1]=mx[0];
                    mxi[1]=mxi[0];

                    mx[0]=x[i][ix[i]];
                    mxi[0]=i;
                }
                else if(x[i][ix[i]]>mx[1]) {
                    mx[1]=x[i].back();
                    mxi[1]=i;
                }

                // cout << r << " " << z << " " << i << endl;

                if(x[i][in[i]]<mn[0]) {
                    mn[1]=mn[0];
                    mni[1]=mni[0];

                    mn[0]=x[i][in[i]];
                    mni[0]=i;
                }
                else if(x[i][in[i]]<mn[1]) {
                    mn[1]=x[i][in[i]];
                    mni[1]=i;
                }
            }

            // cerr << mx[0] << " " << mn[0] << " " << mxi[0] << " " << mni[0] << endl;

            if(mxi[0]!=mni[0]) {
                int i=ix[mxi[0]]--;
                int j=in[mni[0]]++;
                s[mxi[0]][i]=s[mni[0]][j]=r;
                v[mxi[0]]=v[mni[0]]=true;
                now.push_back(mx[0]); now.push_back(mn[0]);
            }
            else {
                assert(mxi[0]!=mni[1] && mxi[1]!=mni[0]);
                if(mx[0]-mn[1]>mx[1]-mn[0]) {
                    int i=ix[mxi[0]]--;
                    int j=in[mni[1]]++;
                    s[mxi[0]][i]=s[mni[1]][j]=r;
                    v[mxi[0]]=v[mni[1]]=true;
                    now.push_back(mx[0]); now.push_back(mn[1]);
                }
                else {
                    int i=ix[mxi[1]]--;
                    int j=in[mni[0]]++;
                    s[mxi[1]][i]=s[mni[0]][j]=r;
                    v[mxi[1]]=v[mni[0]]=true;
                    now.push_back(mx[1]); now.push_back(mn[0]);
                }
            }
        }

        sort(now.begin(), now.end());
        int val=now[sz(now)/2];
        for(int it : now) {
            ret+=abs(it-val);
        }
    }

    allocate_tickets(s);

    return ret;
}
/*
2 3 2
0 2 5
1 1 3

4 2 1
5 9
1 4
3 6
2 7
*/

• 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