本来闲得无聊写个暴力...然后过了
#include <iostream>
#include <cstdio>
using namespace std;

int n;
struct edge
{
	int nxt, to;
}ed[100010];
int head[50010], cnt;
inline void add(int x, int y){ed[++cnt]=(edge){head[x], y};head[x]=cnt;}
int siz[50010];
int f[50010];
int fat[50010];
int mx=1e9;

inline void dfs(int x, int fa)
{
	siz[x] = 1;
	for (register int i = head[x]; i; i = ed[i].nxt)
	{
		int to = ed[i].to;
		if (fa == to) continue;
		fat[to] = x;
		dfs(to, x);
		siz[x] += siz[to];
	}
}

int main()
{
	scanf("%d", &n);
	for (register int i = 1; i < n; i++)
	{
		int x, y;
		scanf("%d%d", &x, &y);
		add(x, y), add(y, x);
	}
	dfs(1, 0);
	for (register int x = 1; x <= n; x ++)
	{
		int sum=0;
		for (register int i = head[x]; i; i = ed[i].nxt)
		{
			int to = ed[i].to;
			if (to == fat[x]) sum = max(sum, siz[1] - siz[x]);
			else sum = max(sum, siz[to]);
		}
		f[x] = sum;
		mx = min(mx, f[x]);
	}
	for (register int i = 1; i <= n; i ++)
	{
		if (f[i] == mx) printf("%d ", i);
	}
	return 0;
}

• 国家反诈机关发来贺电 (8) peterwuyihong 2022-02-18 22:08:15