From 9ebe80f88bf031295cb8a2946ebe77e84dc23cdf Mon Sep 17 00:00:00 2001
From: poma <semenov.roma@gmail.com>
Date: Wed, 10 Feb 2021 09:43:28 +0300
Subject: [PATCH] remove recursion

---
 contracts/TornadoTrees.sol | 31 ++++++++++---------------------
 1 file changed, 10 insertions(+), 21 deletions(-)

diff --git a/contracts/TornadoTrees.sol b/contracts/TornadoTrees.sol
index b66dff8..8e34600 100644
--- a/contracts/TornadoTrees.sol
+++ b/contracts/TornadoTrees.sol
@@ -122,29 +122,18 @@ contract TornadoTrees is EnsResolve {
     } while (direction == elementExists(_tornadoTreesV1, _type, _from));
     uint256 high = direction ? _from : _from + _step;
     uint256 low = direction ? _from - _step : _from;
+    uint256 mid = (high + low) / 2;
 
-    // Perform a binary search on this segment
-    uint256 lastIndex = binarySearch(_tornadoTreesV1, _type, high, low);
-
-    return lastIndex + 1;
-  }
-
-  function binarySearch(
-    ITornadoTreesV1 _tornadoTreesV1,
-    string memory _type,
-    uint256 _high,
-    uint256 _low
-  ) public view returns (uint256) {
-    uint256 mid = (_high + _low) / 2;
-    if (mid == _low) {
-      return mid;
-    }
-
-    if (elementExists(_tornadoTreesV1, _type, mid)) {
-      return binarySearch(_tornadoTreesV1, _type, _high, mid);
-    } else {
-      return binarySearch(_tornadoTreesV1, _type, mid, _low);
+    // Perform a binary search in this segment
+    while (low < mid) {
+      if (elementExists(_tornadoTreesV1, _type, mid)) {
+        low = mid;
+      } else {
+        high = mid;
+      }
+      mid = (high + low) / 2;
     }
+    return mid + 1;
   }
 
   function elementExists(