Submission #1264193

#	Time	Username	Problem	Language	Result	Execution time	Memory
1264193		StefanSebez	Migrations (IOI25_migrations)	C++20	30 / 100	32 ms	1700 KiB

migrations

#include "migrations.h"
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define ll long long
const int N=10050,lg=15;
vector<int>E[N];
int par[N][lg+1],depth[N];
int LCA(int u,int v){
    if(depth[u]<depth[v]) swap(u,v);
    for(int i=lg;i>=0;i--) if(depth[par[u][i]]>=depth[v]) u=par[u][i];if(u==v) return u;
    for(int i=lg;i>=0;i--) if(par[u][i]!=par[v][i]) u=par[u][i],v=par[v][i];return par[u][0];
}
int Dist(int u,int v){return depth[u]+depth[v]-2*depth[LCA(u,v)];}
int dist[N];
void DFS(int u,int p=-1){
    if(p==-1) dist[u]=0;
    else dist[u]=dist[p]+1;
    for(auto i:E[u]) if(i!=p) DFS(i,u);
}
int Dist1(int u,int v){
    DFS(u);
    return dist[v];
}
int U=1,V=1,num[2];
int send_message(int n,int i,int Pi){
    i++,Pi++;
    E[i].pb(Pi);
    E[Pi].pb(i);
    depth[i]=depth[Pi]+1;
    par[i][0]=Pi;
    for(int j=1;j<=lg;j++) par[i][j]=par[par[i][j-1]][j-1];
    if(Dist(U,V)<Dist(U,i)) V=i;
    if(Dist(U,V)<Dist(i,V)) U=i;
    //printf("%i %i: %i %i\n",i,Pi,U,V);
    if(i<n-2*lg-10) return 0;
    if(i==U){
        num[0]=lg;
        return 3;
    }
    if(i==V){
        num[1]=lg;
        return 4;
    }
    if(num[0]<lg){
        int bit=(U-1)>>num[0]&1;
        num[0]++;
        return bit+1;
    }
    if(num[1]<lg){
        int bit=(V-1)>>num[1]&1;
        num[1]++;
        return bit+1;
    }
    return 0;
}

pair<int,int>longest_path(vector<int>S){
    int n=S.size();
    int U=0,V=0;
    int num[2]={0};
    for(int i=0;i<n;i++){
        if(S[i]==0) continue;
        if(S[i]==3){
            num[0]=lg;
            U=i;
        }
        else if(S[i]==4){
            num[1]=lg;
            V=i;
        }
        else{
            if(num[0]<lg){
                if(S[i]==2) U+=1<<num[0];
                num[0]++;
            }
            else if(num[1]<lg){
                if(S[i]==2) V+=1<<num[1];
                num[1]++;
            }
        }
        //printf("{%i %i}\n",U,V);
    }
    return {U,V};
}

• Subtask 0: 0 / 0
• Subtask 1: 30 / 30
• Subtask 2: 0 / 70