Submission #893425

#	Time	Username	Problem	Language	Result	Execution time	Memory
893425		vjudge1	Meetings 2 (JOI21_meetings2)	C++17	4 / 100	4035 ms	132904 KiB

meetings2

#include <bits/stdc++.h>

#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long

using namespace std;

int pow(int a,int b,int m){int ans=1;while(b){if(b&1){ans=(ans*a)%m;}b>>=1;a=(a*a)%m;}return ans;}
int binpow(int a,int b){int ans=1;while(b){if(b&1){ans=(ans*a);}b>>=1;a=(a*a);}return ans;}
	
const int N = 1e5 + 2, inf = 1e9;

vector <int> g[N];
int timer;
int tin[N], tout[N], up[N][30];
int n, deep[N];
 
void dfs (int v, int p = 0, int d = 0) {
	tin[v] = ++timer;
	up[v][0] = p;
	deep[v] = deep[p] + 1;
	for (int i=1; i<=25; ++i)
		up[v][i] = up[up[v][i-1]][i-1];
	for (size_t i=0; i<g[v].size(); ++i) {
		int to = g[v][i];
		if (to != p)
			dfs (to, v, d + 1);
	}
	tout[v] = ++timer;
}
 
bool upper (int a, int b) {
	return tin[a] <= tin[b] && tout[a] >= tout[b];
}

int lca (int a, int b) {
	if(a == b)return a;
	if (upper (a, b))  swap(a, b);
	for (int i=25; i>=0; --i)
		if (! upper (up[a][i], b))
			a = up[a][i];
	return up[a][0];
}
 
int distance(int a, int b){
	int lc = lca(a, b);
	return deep[a] + deep[b] - deep[lc] * 2;
}

main(){
	iostream::sync_with_stdio(false);	
    cin.tie(nullptr);
    cout.tie(nullptr);
    cin >> n;
    for(int i = 0; i < n - 1; i++){
		int a, b;
		cin >> a >> b;
		a--;
		b--;
		g[a].pb(b);
		g[b].pb(a);
	}
	dfs(0, 0);
	for(int i = 1; i <= n; i++){
		int ans = 0;
		for(int bit = 1; bit < (1 << n); bit++){
			if(__builtin_popcount(bit) != i)continue;
			
			vector <int> us, notus;
			//cout <<i <<"->"<< bit << endl;
			for(int j = 0; j < n; j++){
				if(bit & (1 << j)){
					us.pb(j);
				}else
					notus.pb(j);
			}
			vector <int> cnt(n * n, 0);
			for(int x = 0; x < n; x++){
				int sum = 0;
				for(auto y : us){
					sum += distance(x, y);
				}
				cnt[sum]++;
			}
			for(int j = 0; j <= n * n; j++){
				if(cnt[j] > 0){
					ans = max(cnt[j], ans);
					break;
				}
			}
		}
		cout <<  ans << endl;
	}
}

Compilation message (stderr)

meetings2.cpp:54:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   54 | main(){
      | ^~~~

• Subtask 1: 4 / 4
• Subtask 2: 0 / 16
• Subtask 3: 0 / 80