Submission #707363

#	Time	Username	Problem	Language	Result	Execution time	Memory
707363		urosk	Meetings 2 (JOI21_meetings2)	C++14	100 / 100	413 ms	72496 KiB

meetings2

#define here cerr<<"===========================================\n"
#define dbg(x) cerr<<#x<<": "<<x<<endl;
#include "bits/stdc++.h"
//#include <ext/pb_ds/tree_policy.hpp>
//#include <ext/pb_ds/assoc_container.hpp>
#define ld double
#define ll long long
#define llinf 100000000000000000LL // 10^17
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define all(a) a.begin(),a.end()
#define ceri(a,l,r) {cerr<<#a<<": ";for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
#define cer(a) {cerr<<#a<<": ";for(ll x_ : a) cerr<<x_<< " ";cerr<<endl;}

#define daj_mi_malo_vremena ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);

using namespace std;
#define maxn 200005
#define lg 23
ll n;
vector<ll> g[maxn];
vector<ll> v[maxn];
ll dub[maxn],sz[maxn];
ll st[maxn][lg];
ll in[maxn],out[maxn],ti = 0;
ll ans[maxn];
void dfs(ll u,ll p){
    st[u][0] = p;
    sz[u] = 1;
    in[u] = ++ti;
    if(u!=p) dub[u] = dub[p] + 1;
    else dub[u] = 0;
    for(ll s : g[u]){
        if(s==p) continue;
        dfs(s,u);
        sz[u]+=sz[s];
    }
    out[u] = ti-1;
}
ll get(ll u,ll p){
    for(ll s : g[u]){
        if(s==p) continue;
        if(sz[s]*2>=n) return get(s,u);
    }
    return u;
}
ll intree(ll x,ll y){return in[y]<=in[x]&&out[y]>=out[x];}
ll lca(ll x,ll y){
    if(intree(x,y)) return y;
    if(intree(y,x)) return x;
    for(ll j = lg-1;j>=0;j--){
        if(!intree(x,st[y][j])) y = st[y][j];
    }
    return st[y][0];
}
ll dis(ll x,ll y){return dub[x] + dub[y] - 2*dub[lca(x,y)];}
ll c;
void tc(){
    cin >> n;
    for(ll i = 1;i<=n-1;i++){
        ll x,y; cin >> x >> y;
        g[x].pb(y);
        g[y].pb(x);
    }
    dfs(1,1);
    c = get(1,1);
    dfs(c,c);
    for(ll j = 1;j<lg;j++) for(ll i = 1;i<=n;i++) st[i][j] = st[st[i][j-1]][j-1];
    for(ll i = 1;i<=n;i++) v[sz[i]].pb(i);
    ll x = c,y = c,d = 0;
    for(ll i = n/2;i>=1;i--){
        for(ll z : v[i]){
            ll dxz = dis(x,z);
            ll dyz = dis(y,z);
            if(dxz<dyz){
                swap(x,y);
                swap(dxz,dyz);
            }
            if(dxz>d){
                d = dxz;
                y = z;
            }
        }
        ans[i] = d+1;
    }
    for(ll i = 1;i<=n;i++){
        if(i&1) cout<<1<<endl;
        else cout<<ans[i/2]<<endl;
    }
}
int main(){
	daj_mi_malo_vremena
    int t; t = 1;
    while(t--){
        tc();
    }
	return 0;
}
/**
5
1 2
2 3
4 2
3 5

7
1 2
2 3
3 4
4 5
2 6
3 7
**/

• Subtask 1: 4 / 4
• Subtask 2: 16 / 16
• Subtask 3: 80 / 80