Submission #1079249

#	Time	Username	Problem	Language	Result	Execution time	Memory
1079249		oscar1f	Tiles (BOI24_tiles)	C++17	68 / 100	66 ms	17932 KiB

Main

#include<bits/stdc++.h>
using namespace std;

#define int long long

const int INFINI=1000*1000*1000+6,TAILLE_MAX=200*1000+5,COORD_MAX=1000+5;
int nbPoints,maxX,nbImpair;
pair<int,int> initPoint[TAILLE_MAX];
pair<int,int> points[TAILLE_MAX];
int cumu[COORD_MAX][COORD_MAX];
int emboite[TAILLE_MAX];
set<pair<int,int>> enCours;

void fusion(int deb,int fin) {
    set<pair<int,int>>::iterator it;
    enCours.insert({deb,fin});
    nbImpair+=(fin-deb)%2;
    it=enCours.lower_bound({fin,-INFINI});
    int nouvDeb,nouvFin;
    if ((*it).first==fin) {
        nbImpair-=((*it).second-(*it).first)%2;
        nbImpair-=(fin-deb)%2;
        nouvFin=(*it).second;
        enCours.erase(it);
        it=enCours.lower_bound({deb,fin});
        enCours.erase(it);
        fin=nouvFin;
        enCours.insert({deb,fin});
        nbImpair+=(fin-deb)%2;
    }
    it=enCours.lower_bound({deb,fin});
    it--;
    if ((*it).second==deb) {
        nbImpair-=((*it).second-(*it).first)%2;
        nbImpair-=(fin-deb)%2;
        nouvDeb=(*it).first;
        enCours.erase(it);
        it=enCours.lower_bound({deb,fin});
        enCours.erase(it);
        deb=nouvDeb;
        enCours.insert({deb,fin});
        nbImpair+=(fin-deb)%2;
    }
}

void suppr(int deb,int fin) {
    set<pair<int,int>>::iterator it=enCours.lower_bound({deb,fin});
    if ((*it).first==deb) {
        if ((*it).second==fin) {
            nbImpair-=(fin-deb)%2;
            enCours.erase(it);
        }
        else {
            nbImpair-=((*it).second-deb)%2;
            deb=fin;
            fin=(*it).second;
            enCours.erase(it);
            nbImpair+=(fin-deb)%2;
            enCours.insert({deb,fin});
        }
    }
    else {
        it--;
        if ((*it).second==fin) {
            nbImpair-=(fin-(*it).first)%2;
            fin=deb;
            deb=(*it).first;
            enCours.erase(it);
            nbImpair+=(fin-deb)%2;
            enCours.insert({deb,fin});
        }
        else {
            int premDeb=(*it).first,dernFin=(*it).second;
            nbImpair-=(dernFin-premDeb)%2;
            enCours.erase(it);
            enCours.insert({premDeb,deb});
            enCours.insert({fin,dernFin});
            nbImpair+=(deb-premDeb)%2;
            nbImpair+=(dernFin-fin)%2;
        }
    }
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    cin>>nbPoints>>maxX;
    int xNouv,yNouv,posMin=0,xMin=INFINI,yMin=INFINI,maxY=0,somX=0;
    for (int i=0;i<nbPoints;i++) {
        cin>>xNouv>>yNouv;
        if (xNouv<xMin or (xNouv==xMin and yNouv<yMin)) {
            posMin=i;
            xMin=xNouv;
            yMin=yNouv;
        }
        maxY=max(maxY,yNouv);
        somX+=xNouv%2;
        initPoint[i]={xNouv,yNouv};
    }
    int posCour,direc=-1,nbPris=1;
    points[0]={xMin,yMin};
    for (int i=1;i<=nbPoints;i++) {
        //cout<<direc<<" "<<nbPris<<endl;
        posCour=(posMin+i)%nbPoints;
        if (points[nbPris-1].first==initPoint[posCour].first) {
            if (direc==0) {
                points[nbPris-1].second=initPoint[posCour].second;
                //cout<<0<<" "<<initPoint[posCour].first<<" "<<initPoint[posCour].second<<endl;
            }
            else {
                direc=0;
                points[nbPris]=initPoint[posCour];
                nbPris++;
            }
        }
        else {
            if (direc==1) {
                //cout<<1<<" "<<initPoint[posCour].first<<" "<<initPoint[posCour].second<<endl;
                points[nbPris-1].first=initPoint[posCour].first;
            }
            else {
                direc=1;
                points[nbPris]=initPoint[posCour];
                nbPris++;
            }
        }
    }
    nbPoints=nbPris;
    if (direc==0) {
        //cout<<"RETOURNE"<<endl;
        for (int i=0;i<nbPoints/2;i++) {
            swap(points[i],points[nbPoints-1-i]);
        }
    }
    /*for (int i=0;i<nbPoints;i++) {
        cout<<points[i].first<<" "<<points[i].second<<endl;
    }*/
    if (somX==0) {
        vector<tuple<int,int,int>> somTri;
        for (int i=0;i<nbPoints-1;i++) {
            somTri.push_back(make_tuple(points[i].first,points[i].second,i));
        }
        somTri.push_back(make_tuple(INFINI,INFINI,nbPoints));
        sort(somTri.begin(),somTri.end());
        enCours.insert({-INFINI,-42});
        enCours.insert({INFINI,42});
        for (int i=0;i<nbPoints-1;i+=2) {
            if (get<2>(somTri[i])<get<2>(somTri[i+1])) {
                fusion(get<1>(somTri[i]),get<1>(somTri[i+1]));
            }
            else {
                suppr(get<1>(somTri[i]),get<1>(somTri[i+1]));
            }
            if (get<0>(somTri[i])!=get<0>(somTri[i+2]) and nbImpair>0) {
                cout<<get<0>(somTri[i])<<endl;
                return 0;
            } 
        }
        cout<<maxX<<endl;
        return 0;
    }
    if (maxX<=1000 and maxY<=1000) {
        for (int i=0;i<nbPoints;i++) {
            points[i].first++;
            points[i].second++;
        }
        xMin++;
        yMin++;
        maxX++;
        maxY++;
        for (int i=1;i<nbPoints;i++) {
            if (points[i-1].first!=points[i].first) {
                cumu[points[i-1].first][1]++;
                cumu[points[i].first][1]--;
                cumu[points[i-1].first][points[i-1].second]--;
                cumu[points[i].first][points[i].second]++;
            }
        }
        for (int y=1;y<=maxY;y++) {
            for (int x=1;x<=maxX;x++) {
                cumu[x][y]+=cumu[x-1][y]+cumu[x][y-1]-cumu[x-1][y-1];
            } 
        }
        /*for (int y=maxY;y>0;y--) {
            for (int x=1;x<=maxX;x++) {
                cout<<cumu[x][y];
            } 
            cout<<endl;
        }*/
        for (int x=1;x<=maxX;x++) {
            for (int y=1;y<=maxY;y++) {
                if (cumu[x][y]==1) {
                    if (cumu[x+1][y]==1 and cumu[x][y+1]==1 and cumu[x+1][y+1]==1) {
                        emboite[x]=1;
                        cumu[x][y]=0;
                        cumu[x+1][y]=0;
                        cumu[x][y+1]=0;
                        cumu[x+1][y+1]=0;
                        //cout<<x<<" "<<y<<endl;
                    }
                    else {
                        for (int z=x-1;z>=0;z--) {
                            if (emboite[z]==0) {
                                cout<<z<<endl;
                                return 0;
                            }
                        }
                    }
                }
            }
        }
        cout<<maxX-1<<endl;
        return 0;
    }
    int rep=maxX;
    for (int i=1;i<nbPoints;i++) {
        if (points[i].second%2!=yMin%2) {
            rep=min(rep,points[i-1].first);
        }
        if (points[i].first%2!=xMin%2) {
            rep=min(rep,points[i].first-1);
        }
    }
    cout<<rep<<endl;
    /*if (points[0].second%2==points[2].second%2) {
        if (points[0].first%2==points[2].first%2) {
            cout<<points[2].first<<endl;
        }
        else {
            cout<<points[2].first-1<<endl;
        }
    }
    else {
        cout<<xMin<<endl;
    }*/
    return 0;
}
 

• Subtask 1: 4 / 4
• Subtask 2: 9 / 9
• Subtask 3: 11 / 11
• Subtask 4: 19 / 19
• Subtask 5: 0 / 22
• Subtask 6: 25 / 25
• Subtask 7: 0 / 10