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#include <bits/stdc++.h>
using namespace std;

int main() {
  ios_base::sync_with_stdio(false);
  int z;
  cin >> z;
  while (z--) {
    int n;
    cin >> n;
    string s, t;
    cin >> s >> t;
    vector<vector<int>> graph(n);
    for (int i = 0; i < n - 1; ++i) {
      int a, b;
      cin >> a >> b;
      --a;
      --b;
      graph[a].push_back(b);
      graph[b].push_back(a);
    }
    if (n==1) {
      cout << (s[0] == t[0] ? "TAK" : "NIE");
      continue;
    }
    bool is_path = true;
    for (int i = 0; i < n; ++i) {
      if (graph[i].size() >= 3)
        is_path = false;
    }
    if (is_path) {
      int leaf = -1;
      for (int i = 0; i < n; ++i)
        if (graph[i].size() == 1)
          leaf = i;
      assert(leaf != -1);
      int changes_s = 0, changes_t = 0;
      int cur = leaf, prv = -1;
      do {
        int nxt = graph[cur][0];
        if (nxt == prv)
          nxt = graph[cur][1];
        if (s[cur] != s[nxt])
          changes_s++;
        if (t[cur] != t[nxt])
          changes_t++;
        prv = cur;
        cur = nxt;
      } while (graph[cur].size() != 1);
      if (s[leaf] != t[leaf])
        changes_s--;
      if (changes_s % 2 != changes_t % 2)
        changes_s--;
      cout << (changes_s >= changes_t ? "TAK" : "NIE") << endl;
    } else {
      // 1) s is mono, t contains other color -> NO
      bool is_s_monocolor = true;
      for (int i = 0; i < n - 1; ++i)
        if (s[i] != s[i + 1])
          is_s_monocolor = false;
      if (is_s_monocolor) {
        bool does_t_contain_other_color = false;
        for (char c : t)
          if (c != s[0])
            does_t_contain_other_color = true;
        if (does_t_contain_other_color) {
          cout << "NIE" << endl;
          continue;
        }
      }
      // 2) t is proper colors, s is different -> NO
      bool is_t_proper = true;
      for (int u = 0; u < n; ++u)
        for (int v : graph[u])
          if (t[u] == t[v])
            is_t_proper = false;
      if (is_t_proper && s != t) {
        cout << "NIE" << endl;
        continue;
      }
      cout << "TAK" << endl;
    }
  }
}