#include <iostream>#include <string>#include <vector>#include <cstring>#include <cstdio>#include <map>#include <queue>#include <algorithm>#include <stack>#include <cstring>#include <cmath>#include <set>#include <vector>using namespace std;template <class T>inline bool rd(T &ret) {char c; int sgn;if (c = getchar(), c == EOF) return 0;while (c != '-' && (c<'0' || c>'9')) c = getchar();sgn = (c == '-') ? -1 : 1;ret = (c == '-') ? 0 : (c – '0');while (c = getchar(), c >= '0'&&c <= '9') ret = ret * 10 + (c – '0');ret *= sgn;return 1;}template <class T>inline void pt(T x) {if (x < 0) {putchar('-');x = -x;}if (x > 9) pt(x / 10);putchar(x % 10 + '0');}typedef long long ll;typedef pair<int, int> pii;const int inf = 1e9;const int N = 1e5+10;int n;int num[N], dp[N], siz, root;bool vis[N];vector<int>G[N];char s[N];void getroot(int u, int fa) {dp[u] = 0; num[u] = 1;for (auto v : G[u]) {if (vis[v] || v == fa)continue;getroot(v, u);num[u] += num[v];dp[u] = max(num[v], dp[u]);}dp[u] = max(dp[u], siz – num[u]);if (dp[u] < dp[root])root = u;}void work(int u, int fa, int dep) {root = 0; siz = num[u];getroot(u, fa);s[root] = dep + 'A';vis[root] = true;for (auto v : G[root]) {if (vis[v])continue;work(v, u, dep + 1);}}void init() {dp[0] = num[1] = n;memset(vis, 0, sizeof vis);}int main() {rd(n);for (int i = 1, u, v; i < n; i++) {rd(u); rd(v); G[u].push_back(v); G[v].push_back(u);}init();work(1, 1, 0);for (int i = 1; i <= n; i++)putchar(s[i]), putchar(' ');return 0;}
，躲在墙角、掩藏那孤独而又不奢怜悯的伤…
