1 files changed, 15 insertions, 0 deletions
diff --git a/content/graph/treeIsomorphism.cpp b/content/graph/treeIsomorphism.cpp
new file mode 100644
index 0000000..355fefb
--- /dev/null
+++ b/content/graph/treeIsomorphism.cpp
@@ -0,0 +1,15 @@
+vector<vector<int>> adj;
+map<vector<int>, int> known; // dont reset!
+
+int treeLabel(int v, int from = -1) {
+	vector<int> children;
+	for (int u : adj[v]) {
+		if (u == from) continue;
+		children.push_back(treeLabel(u, v));
+	}
+	sort(all(children));
+	if (known.find(children) == known.end()) {
+		known[children] = sz(known);
+	}
+	return known[children];
+}