Submission #1300609

#	Time	Username	Problem	Language	Result	Execution time	Memory
1300609		Zbyszek99	Meetings 2 (JOI21_meetings2)	C++20	100 / 100	70 ms	31468 KiB

meetings2

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ld long double
#define ull unsigned long long
#define ff first
#define ss second
#define pii pair<int,int>
#define pll pair<long long, long long>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
using namespace __gnu_pbds;
using namespace std;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll los(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e9+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9+7;

int ans[200001];
vi graph[200001];
int sub[200001];
int depth[200001];
vi dp[200001];

void dfs(int v, int pop, int d)
{
    depth[v] = d++;
    sub[v] = 1;
    forall(it,graph[v])
    {
        if(it != pop)
        {
            dfs(it,v,d);
            sub[v] += sub[it]; 
        }
    }
}

void dfs_dp(int v, int pop)
{
    depth[v] = depth[pop]+1;
    sub[v] = 1;
    int cnt = 0;
    int fff = -1;
    forall(it,graph[v]) if(it != pop)
    {
        dfs_dp(it,v);
        sub[v] += sub[it];
        fff = it;
        cnt++;
    }
    if(v != pop)
    {
        ans[sub[v]*2] = max(ans[sub[v]*2],depth[v]);
    }
    if(cnt == 0)
    {
        dp[v].pb(depth[v]);
        return;
    }
    swap(dp[v],dp[fff]);
    forall(it,graph[v])
    {
        if(it == fff || it == pop) continue;
        if(siz(dp[v]) < siz(dp[it]))
        {
            swap(dp[v],dp[it]);
        }
        rep(j,siz(dp[it]))
        {
            ans[(j+1)*2] = max(ans[(j+1)*2],dp[v][j]+dp[it][j]-2*depth[v]+1);
            dp[v][j] = max(dp[v][j],dp[it][j]);
        }
    }
    while(siz(dp[v]) < sub[v])
    {
        dp[v].pb(depth[v]);
    }
}

inline int fastRead() {
    int x = 0, c = getchar_unlocked();
    while (c < '0' || c > '9') c = getchar_unlocked();
    while (c >= '0' && c <= '9') {
        x = x * 10 + (c - '0');
        c = getchar_unlocked();
    }
    return x;
}

int main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    //random_start();
    int n = fastRead();
    ans[n] = 1;
    rep(i,n-1)
    {
        int a = fastRead(),b = fastRead();
        graph[a].pb(b);
        graph[b].pb(a);
    }
    dfs(1,1,0);
    int centr = 1;
    int pop = -1;
    while(true)
    {
        pii best = {-1e9,-1};
        forall(it,graph[centr])
        {
            if(it != pop) best = max(best,{sub[it],it});
        }
        if(best.ff > n/2)
        {
            pop = centr;
            centr = best.ss;
        }
        else break;
    }
    depth[centr] = 0;
    dfs_dp(centr,centr);
    for(int i = n-1; i >= 1; i--)
    {
        ans[i] = max(ans[i],ans[i+1]);
    }
    rep2(i,1,n) if(i % 2 == 1) cout << "1\n"; else cout << ans[i] << "\n";
}

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