#include <bits/stdc++.h>
using ll = long long;
const int N = 5e4 + 10;

std::vector<int> g[N];
int n, s, t, dep[N], bl[20][N], in[N], dc;
void dfs(int u, int ff) {
  bl[0][in[u] = ++dc] = ff, dep[u] = dep[ff] + 1;
  for (int v : g[u]) if (v != ff) dfs(v, u);
}
bool cmp(int u, int v) { return dep[u] < dep[v]; }
int lca(int u, int v) {
  if (u == v) return u;
  u = in[u], v = in[v];
  if (u > v) std::swap(u, v);
  u++;
  int k = 31 - __builtin_clz(v - u + 1);
  return std::min(bl[k][u], bl[k][v - (1 << k) + 1], cmp);
}
int dis(int u, int v) { return dep[u] + dep[v] - 2 * dep[lca(u, v)]; }

std::mt19937 rnd(std::chrono::system_clock::now().time_since_epoch().count());
void mian() {
  std::cin >> n >> s >> t;
  for (int i = 1; i <= n; i++) g[i].clear();
  for (int i = 1, u, v; i < n; i++) {
    std::cin >> u >> v;
    g[u].push_back(v), g[v].push_back(u);
  }
  dc = 0, dfs(1, 0);
  for (int i = 1; i <= 16; i++) for (int j = 1; j + (1 << i) - 1<= n; j++) 
    bl[i][j] = std::min(bl[i - 1][j], bl[i - 1][j + (1 << (i - 1))], cmp);
  if (n <= 9) {
    std::pair<int, std::vector<int>> mn{(int)1e9, {}};
    std::vector<int> id(n);
    std::iota(id.begin(), id.end(), 1);
    do {
      if (id[0] != s) continue;
      if (id[n - 1] != t) continue;
      int d = 0;
      for (int i = 1; i < n; i++) d ^= dis(id[i], id[i - 1]);
      if (d < mn.first) mn = {d, id};
    } while (std::next_permutation(id.begin(), id.end()));
    for (int i = 0; i < n; i++) std::cout << mn.second[i] << " \n"[i == n - 1];
  } else {
    std::vector<int> id(n);
    std::iota(id.begin(), id.end(), 1);
    std::swap(id[0], *std::find(id.begin(), id.end(), s));
    std::swap(id[n - 1], *std::find(id.begin(), id.end(), t));
    // std::shuffle(id.begin() + 1, id.end() - 1, rnd);
    int cur = 0;
    for (int i = 0; i < n - 1; i++)
      cur ^= dis(id[i], id[i + 1]);
    if (cur <= 1) {
      for (int i = 0; i < n; i++) std::cout << id[i] << " \n"[i == n - 1];
      return;
    } 
    for (;;) {
      int u = std::uniform_int_distribution<int>(1, n - 2)(rnd);
      int v = std::uniform_int_distribution<int>(1, n - 2)(rnd);
      while (u == v) v = std::uniform_int_distribution<int>(1, n - 2)(rnd);
      cur ^= dis(id[u - 1], id[u]) ^ dis(id[u], id[u + 1]) ^ dis(id[v - 1], id[v]) ^ dis(id[v], id[v + 1]);
      std::swap(id[u], id[v]);
      cur ^= dis(id[u - 1], id[u]) ^ dis(id[u], id[u + 1]) ^ dis(id[v - 1], id[v]) ^ dis(id[v], id[v + 1]);
      if (cur <= 1) {
        for (int i = 0; i < n; i++) std::cout << id[i] << " \n"[i == n - 1];
        return;
      }
    }
  }
}

int main() {
  std::cin.tie(0)->sync_with_stdio(0);
  int t;
  std::cin >> t;
  while (t--) mian();
}