Submission #672256

#	Time	Username	Problem	Language	Result	Execution time	Memory
672256		alvingogo	Flight to the Ford (BOI22_communication)	C++17	84 / 100	3647 ms	2372 KiB

communication

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

vector<int> use(vector<int> &a,vector<int> &b,int x,int t){
    sort(a.begin(),a.end());
    sort(b.begin(),b.end());
    int as=a.size();
    int bs=b.size();
    vector<int> la,ra,lb,rb;
    if(as+bs<=2){
        vector<int> z;
        for(auto h:a){
            z.push_back(h);
        }
        for(auto h:b){
            z.push_back(h);
        }
        if(z.size()==1){
            int u=z[0];
            z.push_back(u);
        }
        return z;
    }
    else if(as+bs==3){
        vector<int> g;
        for(auto h:a){
            g.push_back(h);
        }
        for(auto h:b){
            g.push_back(h);
        }
        sort(g.begin(),g.end());
        int u=-1;
        for(int i=0;i<3;i++){
            if(g[i]==x){
                u=i;
            }
        }
        if(t==0){
            return g;
        }
        else{
            string s[3]={"1111","0001","1000"};
            if(u==-1){
                string z;
                for(int j=0;j<4;j++){
                    z+=char('0'+receive());
                }
                int flag=-1;
                for(int i=0;i<3;i++){
                    int lst=0;
                    for(int j=0;j<4;j++){
                        if(s[i][j]!=z[j]){
                            if(lst){
                                flag=i;
                                break;
                            }
                            else{
                                lst=1;
                            }
                        }
                        else{
                            lst=0;
                        }
                    }
                }
                vector<int> ret;
                for(int i=0;i<3;i++){
                    if(i!=flag){
                        ret.push_back(g[i]);
                    }
                }
                return ret;
            }
            else{
                for(int i=0;i<4;i++){
                    send(int(s[u][i]-'0'));
                }
                return vector<int>();
            }   
        }
    }
    int nxt=-1;
    for(int i=0;i<as/2;i++){
        if(a[i]==x){
            nxt=0;
        }
        la.push_back(a[i]);
        rb.push_back(a[i]);
    }
    for(int i=as/2;i<as;i++){
        if(a[i]==x){
            nxt=1;
        }
        ra.push_back(a[i]);
        lb.push_back(a[i]);
    }
    for(int i=0;i<(bs+1)/2;i++){
        if(b[i]==x){
            nxt=0;
        }
        la.push_back(b[i]);
    }
    for(int i=(bs+1)/2;i<bs;i++){
        if(b[i]==x){
            nxt=1;
        }
        ra.push_back(b[i]);
    }
    int dd;
    if(nxt==-1){
        dd=receive();
    }
    else{
        dd=send(nxt);
    }
    if(dd==0){
        return use(la,lb,x,t);
    }
    else{
        return use(ra,rb,x,t);
    }
}
const int Bd=31638,Bd2=178;
vector<int> emp;
vector<int> solve2(int N,int X){
    int a=-1,c=-1;
    if(X!=-1){
        a=X/Bd2;
        c=X%Bd2;
    }
    vector<int> v(max(3,N/Bd2+1));
    iota(v.begin(),v.end(),0);
    auto e=use(v,emp,a,0);
    vector<int> w(Bd2);
    iota(w.begin(),w.end(),0);
    auto f=use(w,emp,c,0);
    vector<int> z;
    for(auto h:e){
        for(auto y:f){
            if(h*Bd2+y<0 || h*Bd2+y>=N){
                continue;
            }
            z.push_back(h*Bd2+y);
        }
    }
    sort(z.begin(),z.end());
    return z;
}
vector<int> solve(int N,int X){
    int a=-1,c=-1;
    if(X!=-1){
        a=X/Bd;
        c=X%Bd;
    }
    auto e=solve2(max(3,N/Bd+1),a);
    auto f=solve2(Bd,c);
    vector<int> z;
    for(auto h:e){
        for(auto y:f){
            if(h*Bd+y<=0 || h*Bd+y>N){
                continue;
            }
            z.push_back(h*Bd+y);
        }
    }
    sort(z.begin(),z.end());
    z.erase(unique(z.begin(),z.end()),z.end());
    return use(z,emp,X,1);
}
void encode(int N,int X){
    solve(N,X);
}

pair<int,int> decode(int N){
    auto h=solve(N,-1);
    int x=h.size();
    return {h[0],h[min(x-1,1)]};
}

• Subtask 1: 15 / 15
• Subtask 2: 69.000025 / 85