Submission #1135242

#	Time	Username	Problem	Language	Result	Execution time	Memory
1135242		alir3za_zar3	Village (BOI20_village)	C++20	50 / 100	42 ms	18588 KiB

Village

// Alir3za.Zar3 -> Shiraz , Iran
#include <bits/stdc++.h>
using namespace std;
#define         int          long long
#define   loop(i , l , r)    for (int i=l; i<=r; i+=1)
#define    arc(i , r , l)    for (int i=r; i>=l; i-=1)

const int N = 1e5+7;
int n,Lo,Hi=0 , lo[N],hi[N],sz[N],eu[N],q[N],T;
vector<int> e[N];

void brain_DFS (int v , int p)
{
    sz[v] = 1; 
    eu[v]=++T; q[T]=v;
    for (auto to : e[v])
    {
        if (to == p){ continue; }
        brain_DFS(to,v);
        sz[v] += sz[to];
        Hi += min(sz[to],n-sz[to]);
    }
    if (lo[v] == v)
    {
        if (v==p)
            swap(lo[v],lo[e[v].front()]);
        else 
            swap(lo[v],lo[p]);
        Lo += 2;
    }
    if (v!=1)
    {
        int combine = min(sz[p],sz[v]);
        int l=eu[v]-1 , r=eu[p]-1;
        loop(i,1,combine)
        {
            ++l; ++r;
            swap(hi[q[l]],hi[q[r]]);
        } 
    }
}

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);     cout.tie(0);
 
    cin >> n;
    loop(i,1,n)
    { 
        lo[i] = hi[i] = i; 
    }
    loop(i,1,n-1)
    {
        int u,v; cin >> u >> v;
        e[u].push_back(v);
        e[v].push_back(u);
    }
    brain_DFS(1,1);
    cout << Lo << " " << 2*Hi << '\n';
    loop(i,1,n){ cout << lo[i] << " "; }
    cout << '\n';
    loop(i,1,n){ cout << hi[i] << " "; }
    cout << '\n';
}

• Subtask 1: 6 / 12
• Subtask 2: 19 / 38
• Subtask 3: 25 / 50