From aef6dd715bf45731b5bef39888a73ca5c75f295e Mon Sep 17 00:00:00 2001
From: birds3345 <31601136+birds3345@users.noreply.github.com>
Date: Wed, 17 Jul 2024 13:46:00 -0400
Subject: [PATCH] make find iterative

---
 EqSat/src/UnionFind.cpp | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/EqSat/src/UnionFind.cpp b/EqSat/src/UnionFind.cpp
index 536de271..ec638628 100644
--- a/EqSat/src/UnionFind.cpp
+++ b/EqSat/src/UnionFind.cpp
@@ -30,13 +30,18 @@ Id UnionFind::find(Id id)
 {
     LUAU_ASSERT(size_t(id) < parents.size());
 
+    Id set = const_cast<const UnionFind*>(this)->find(id);
+
     // An e-class id 𝑎 is canonical iff find(𝑎) = 𝑎.
-    if (id != parents[size_t(id)])
+    while (id != parents[size_t(id)])
+    {
         // Note: we don't update the ranks here since a rank
         // represents the upper bound on the maximum depth of a tree
-        parents[size_t(id)] = find(parents[size_t(id)]);
+        parents[size_t(id)] = set;
+        id = parents[size_t(id)];
+    }
     
-    return parents[size_t(id)];
+    return set;
 }
 
 void UnionFind::merge(Id a, Id b)