codeforces: 1003

codeforces/1003/f.cc

@@ -0,0 +1,134 @@
+//  {{{
+#include <bits/stdc++.h>
+
+// https://codeforces.com/blog/entry/96344
+
+#pragma GCC optimize("O2,unroll-loops")
+#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
+
+using namespace std;
+
+template <typename T>
+constexpr T MIN = std::numeric_limits<T>::min();
+
+template <typename T>
+constexpr T MAX = std::numeric_limits<T>::max();
+
+template <typename T>
+[[nodiscard]] static T sc(auto &&x) {
+  return static_cast<T>(x);
+}
+
+template <typename T>
+[[nodiscard]] static T sz(auto &&x) {
+  return static_cast<T>(x.size());
+}
+
+template <typename... Args>
+void pr(std::format_string<Args...> fmt, Args &&...args) {
+  std::print(fmt, std::forward<Args>(args)...);
+}
+
+template <typename... Args>
+void pr(std::format_string<Args...> fmt) {
+  std::print(fmt);
+}
+
+template <typename... Args>
+void prln(std::format_string<Args...> fmt, Args &&...args) {
+  std::println(fmt, std::forward<Args>(args)...);
+}
+
+template <typename... Args>
+void prln(std::format_string<Args...> fmt) {
+  std::println(fmt);
+}
+
+void prln() {
+  std::println();
+}
+
+void prln(auto const &t) {
+  std::println("{}", t);
+}
+
+using ll = long long;
+using ld = long double;
+template <typename T>
+using vec = std::vector<T>;
+
+#define ff first
+#define ss second
+#define eb emplace_back
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+//  }}}
+
+void solve() {
+  int n;
+  cin >> n;
+  vec<int> a(n + 1);
+  for (int i = 1; i < sz<int>(a); ++i) {
+    cin >> a[i];
+  }
+
+  vec<vec<int>> tree(n + 1, vec<int>());
+  string ans(n, '0');
+
+  int root;
+  for (int i = 0; i < n - 1; ++i) {
+    int u, v;
+    cin >> u >> v;
+    root = u;
+    tree[u].pb(v);
+    tree[v].pb(u);
+  }
+
+  unordered_map<int, unordered_map<int, int>> children;
+  vec<int> par(n + 1, -1);
+  par[root] = root;
+
+  queue<int> q{{root}};
+
+  while (!q.empty()) {
+    int size = sz<int>(q);
+    while (size--) {
+      auto u = q.front();
+      q.pop();
+      for (auto v : tree[u]) {
+        if (par[v] != -1)
+          continue;
+        par[v] = u;
+        q.push(v);
+        if (++children[u][a[v]] == 2)
+          ans[a[v] - 1] = '1';
+      }
+    }
+  }
+
+  q.push(root);
+
+  for (int u = 1; u <= n; ++u) {
+    if (par[u] != u && a[u] == a[par[u]] ||
+        par[u] != root && a[u] == a[par[par[u]]])
+      ans[a[u] - 1] = '1';
+  }
+
+  prln("{}", ans);
+}
+
+// {{{
+int main() {
+  cin.tie(nullptr)->sync_with_stdio(false);
+
+  int t = 1;
+  cin >> t;
+
+  while (t--) {
+    solve();
+  }
+
+  return 0;
+}
+// }}}