Submission #596291

#	Time	Username	Problem	Language	Result	Execution time	Memory
596291		Deepesson	Event Hopping (BOI22_events)	C++17	100 / 100	398 ms	28988 KiB

events

#include <bits/stdc++.h>
#define MAX 200010
#define LSB(A) (A&(-A))
#define LOG 20
int N,Q;
typedef std::pair<int,int> pii;
std::vector<pii> eventos;

std::vector<int> add[MAX];

std::vector<int> rem[MAX];

int ft[MAX];

typedef std::pair<int,int*> pipo;
int custos[101000];
int trava;

int armazena[MAX];
int valor[MAX];
int jump[MAX][LOG];

void gera_conexoes(){
    std::deque<pii> st;
    ///Menor indice L em que o final esteja presente entre L e R
    for(int i=MAX-1;i!=-1;--i){
        ///Adiciona o finalzinho
        pii menor = {1e9+1,1e9+1};
        for(auto&x:rem[i]){
            pii conj = {eventos[x].first,x};
            menor=std::min(menor,conj);
        }
        if(menor.first!=1e9+1){
            while(st.size()&&st.front().first>=menor.first){
                st.pop_front();
            }
            st.push_front(menor);
        }
        ///Pega o valor
        for(auto&x:add[i]){
            int l=0,r=st.size()-1;
            while(l<r){
                int m = (l+r+1)/2;
                if(eventos[st[m].second].second<=eventos[x].second){
                    l=m;
                }else r=m-1;
            }
            jump[x][0]=st[l].second;
        }
    }
}

int jumps(int a,int b){
    int pos = a;
    for(int i=LOG-1;i!=-1;--i){
        if(((1<<i)&b)&&jump[pos][i]!=-1){
            pos=jump[pos][i];
        }
    }
    return pos;
}

int tabp5[5005][5005];
int main()
{
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    std::cout.tie(0);
    std::cin>>N>>Q;
    for(int i=0;i!=N;++i){
        int a,b;
        std::cin>>a>>b;
        eventos.push_back({a,b});
    }

    {
        std::vector<pipo> comprime;
        for(auto&x:eventos){
            comprime.push_back({x.first,&x.first});
            comprime.push_back({x.second,&x.second});
        }
        std::sort(comprime.begin(),comprime.end());
        int last=-1,cord=1;
        for(auto&x:comprime){
            if(x.first!=last){
                last=x.first;
                ++cord;
            }
            *x.second=cord;
        }
        trava=cord;
    }
    for(int i=0;i!=N;++i){
        add[eventos[i].first].push_back(i);
        rem[eventos[i].second].push_back(i);
    }
    gera_conexoes();
   // for(int i=0;i!=N;++i)if(jump[i][0]==i)jump[i][0]=-1;
    for(int j=1;j!=LOG;++j){
        for(int i=0;i!=N;++i){
            if(jump[i][j-1]==-1)jump[i][j]=-1;
            else
            jump[i][j]=jump[jump[i][j-1]][j-1];
        }
    }

    for(int i=0;i!=Q;++i){
        int s,t;
        std::cin>>s>>t;
        --s;--t;
        if(s==t){
            std::cout<<"0\n";
            continue;
        }
        if(eventos[t].second<eventos[s].second){
            std::cout<<"impossible\n";
            continue;
        }
        int cord = eventos[s].second;

        int l=0,r=1e9;
        while(l<r){
            int m = (l+r)/2;
            int q=jumps(t,m);
            if(eventos[q].first<=cord){
                r=m;
            }else l=m+1;
        }
       // std::cout<<"ve "<<l<<"\n";
        int q=jumps(t,l);
        if(q!=s){
            ++l;
        }
      //  std::cout<<"Val R: "<<r<<"\n";
        if(r==1e9){
            std::cout<<"impossible\n";
            continue;
        }
        std::cout<<l<<"\n";
    }
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 30 / 30