Submission #990699

#	Time	Username	Problem	Language	Result	Execution time	Memory
990699		kanpham	Village (BOI20_village)	C++17	0 / 100	2 ms	10584 KiB

Village

#include<bits/stdc++.h>
#define int long long
#define pii pair<int,int>
#define pb push_back
#define in insert
#define fi first
#define se second
using namespace std;
const int mod=1000000007;
const int N=2e5+7;
const int inf=1e17;
int a[N];
int n;
vector<int>dsk[N];
int d[N],dinh,h[N];
set<pii>s;
void dfs0(int u,int par){
    if(d[u]>d[dinh])dinh=u;
    s.insert({d[u],u});
    for(auto v:dsk[u]){
        if(v==par)continue;
        d[v]=d[u]+1;
        h[v]=h[u]+1;
        dfs0(v,u);
    }
}
int ans[N],kc[N];
bool ok[N];
void dfs(int u,int par){
    pii cc=*s.rbegin();
    s.erase(s.find(cc));
    ans[u]=cc.se;
    ans[cc.se]=u;
    kc[u]=cc.fi-h[u];
    kc[cc.se]=cc.fi-h[u];
    ok[u]=true;
    ok[cc.se]=true;
    for(auto v:dsk[u]){
        if(v==par||ok[v])continue;
        dfs(v,u);
    }
}
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);

    cin>>n;
    for(int i=1;i<n;i++){
        int u,v;cin>>u>>v;
        dsk[u].pb(v);
        dsk[v].pb(u);
    }
    dfs0(1,1);
    d[dinh]=0;
    h[dinh]=0;
    s.clear();
    int ngu=dinh;
    dfs0(dinh,0);
    dinh=ngu;
    dfs(dinh,dinh);
    int sum=0;
    for(int i=1;i<=n;i++)sum+=kc[i];
    cout<<sum<<'\n';
    for(int i=1;i<=n;i++)cout<<ans[i]<<" ";
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 38
• Subtask 3: 0 / 50