seeing if this is enough

Author: lrvideckis

library/trees/centroid_decomp_uncommon/count_paths_per_length.hpp

@@ -7,38 +7,36 @@
 //! @time O(n log^2 n)
 //! @space this function allocates/returns various vectors
 //! which are each O(n)
-vector<ll> count_paths_per_length(const vector<vi>& adj) {
+vector<ll> count_paths_per_length(const auto& adj) {
   vector<ll> num_paths(sz(adj));
-  centroid(adj,
-    [&](const vector<vi>& cd_adj, int cent, int) {
-      vector<vector<double>> child_depths;
-      for (int v : cd_adj[cent]) {
-        child_depths.emplace_back(1, 0.0);
-        for (queue<pii> q({{v, cent}}); !empty(q);) {
-          child_depths.back().push_back(sz(q));
-          queue<pii> new_q;
-          while (!empty(q)) {
-            auto [u, p] = q.front();
-            q.pop();
-            for (int w : cd_adj[u]) {
-              if (w == p) continue;
-              new_q.emplace(w, u);
-            }
+  centroid(adj, [&](const auto& cd_adj, int cent, int) {
+    vector<vector<double>> child_depths;
+    for (int v : cd_adj[cent]) {
+      child_depths.emplace_back(1, 0.0);
+      for (queue<pii> q({{v, cent}}); !empty(q);) {
+        child_depths.back().push_back(sz(q));
+        queue<pii> new_q;
+        while (!empty(q)) {
+          auto [u, p] = q.front();
+          q.pop();
+          for (int w : cd_adj[u]) {
+            if (w == p) continue;
+            new_q.emplace(w, u);
           }
-          swap(q, new_q);
         }
+        swap(q, new_q);
       }
-      ranges::sort(child_depths, {},
-        [&](auto& x) { return sz(x); });
-      vector total_depth(1, 1.0);
-      for (auto& cnt_depth : child_depths) {
-        auto prod = conv(total_depth, cnt_depth);
-        rep(i, 1, sz(prod)) num_paths[i] +=
-          llround(prod[i]);
-        total_depth.resize(sz(cnt_depth));
-        rep(i, 1, sz(cnt_depth)) total_depth[i] +=
-          cnt_depth[i];
-      }
-    });
+    }
+    ranges::sort(child_depths, {},
+      [&](auto& x) { return sz(x); });
+    vector total_depth(1, 1.0);
+    for (auto& cnt_depth : child_depths) {
+      auto prod = conv(total_depth, cnt_depth);
+      rep(i, 1, sz(prod)) num_paths[i] += llround(prod[i]);
+      total_depth.resize(sz(cnt_depth));
+      rep(i, 1, sz(cnt_depth)) total_depth[i] +=
+        cnt_depth[i];
+    }
+  });
   return num_paths;
 }

tests/library_checker_aizu_tests/trees/count_paths_per_length.test.cpp

@@ -6,7 +6,7 @@ int main() {
   cin.tie(0)->sync_with_stdio(0);
   int n;
   cin >> n;
-  vector<vector<int>> adj(n);
+  vector<basic_string<int>> adj(n);
   for (int i = 0; i < n - 1; i++) {
     int u, v;
     cin >> u >> v;