diff --git a/content/graphs/chu-liu.cpp b/content/graphs/chu-liu.cpp
new file mode 100644
index 0000000..03704d0
--- /dev/null
+++ b/content/graphs/chu-liu.cpp
@@ -0,0 +1,79 @@
+/*
+ *Description:* Minimum spanning arborescence (directed MST), Edmonds/Chu-Liu algorithm
+ *Complexity:* $O(n m)$, returns -1 if not reachable
+ *Status:* Tested
+*/
+template <class T> struct chu_liu {
+  struct edge {
+    int u, v, id;
+    T len;
+  };
+  int n;
+  vector<edge> e;
+  vector<int> inc, dec, take, pre, num, id, vis;
+  vector<T> inw;
+  T INF;
+
+  chu_liu(int n) : n(n), pre(n), num(n), id(n), vis(n), inw(n) {
+    INF = numeric_limits<T>::max() / 2;
+  }
+  void add_edge(int x, int y, T w) {
+    inc.push_back(0), dec.push_back(0), take.push_back(0);
+    e.push_back({x, y, (int)e.size(), w});
+  }
+  T solve(int root) {
+    auto e2 = e;
+    T ans = 0;
+    int eg = e.size() - 1, pos = eg;
+    while (1) {
+      for (int i = 0; i < n; i++)
+        inw[i] = INF, id[i] = vis[i] = -1;
+      for (auto &ed : e2)
+        if (ed.len < inw[ed.v])
+          inw[ed.v] = ed.len, pre[ed.v] = ed.u, num[ed.v] = ed.id;
+      inw[root] = 0;
+      for (int i = 0; i < n; i++)
+        if (inw[i] == INF)
+          return -1;
+      int tot = -1;
+      for (int i = 0; i < n; i++) {
+        ans += inw[i];
+        if (i != root)
+          take[num[i]]++;
+        int j = i;
+        while (vis[j] != i && j != root && id[j] < 0)
+          vis[j] = i, j = pre[j];
+        if (j != root && id[j] < 0) {
+          id[j] = ++tot;
+          for (int k = pre[j]; k != j; k = pre[k])
+            id[k] = tot;
+        }
+      }
+      if (tot < 0)
+        break;
+      for (int i = 0; i < n; i++)
+        if (id[i] < 0)
+          id[i] = ++tot;
+      n = tot + 1;
+      int j = 0;
+      for (int i = 0; i < (int)e2.size(); i++) {
+        int v = e2[i].v;
+        e2[j] = {id[e2[i].u], id[e2[i].v], e2[i].id, e2[i].len - inw[v]};
+        if (e2[j].u != e2[j].v) {
+          inc.push_back(e2[i].id);
+          dec.push_back(num[v]);
+          take.push_back(0);
+          e2[j++].id = ++pos;
+        }
+      }
+      e2.resize(j);
+      root = id[root];
+    }
+    while (pos > eg) {
+      if (take[pos])
+        take[inc[pos]]++, take[dec[pos]]--;
+      pos--;
+    }
+    return ans;
+  }
+};
\ No newline at end of file
diff --git a/tracker.yaml b/tracker.yaml
index 67b5931..65e3dea 100644
--- a/tracker.yaml
+++ b/tracker.yaml
@@ -128,6 +128,7 @@ content:
     - 3-cycle.cpp
     - chromatic-number.cpp
     - undirected-euler-trail.cpp
+    - chu-liu.cpp
   - geometry:
     - point-2d.cpp
     - convex-hull.cpp
@@ -154,5 +155,5 @@ content:
     - simulated-annealing.cpp
 
 
-  - utilities:
-    - berlekamp-massey.py
+  - utilities:
+    - berlekamp-massey.py