diff --git a/RedBlackNode.jar b/RedBlackNode.jar
index 7e987c9cc..f44200aa7 100644
Binary files a/RedBlackNode.jar and b/RedBlackNode.jar differ
diff --git a/src/com/github/btrekkie/red_black_node/RedBlackNode.java b/src/com/github/btrekkie/red_black_node/RedBlackNode.java
index 70bcb229a..91685acba 100644
--- a/src/com/github/btrekkie/red_black_node/RedBlackNode.java
+++ b/src/com/github/btrekkie/red_black_node/RedBlackNode.java
@@ -360,7 +360,7 @@ public abstract class RedBlackNode<N extends RedBlackNode<N>> implements Compara
      * @param allowDuplicates Whether to insert newNode if there is an equal node in the tree.  To check whether we
      *     inserted newNode, check whether newNode.parent is null and the return value differs from newNode.
      * @param comparator A comparator indicating where to put the node.  If this is null, we use the nodes' natural
-     *     order, as in N.compare.
+     *     order, as in N.compareTo.
      * @return The root of the resulting tree.
      */
     public N insert(N newNode, boolean allowDuplicates, Comparator<? super N> comparator) {
@@ -829,10 +829,14 @@ public abstract class RedBlackNode<N extends RedBlackNode<N>> implements Compara
      * inserting all of the nodes in "last".
      */
     public N concatenate(N last) {
+        if (parent != null) {
+            throw new IllegalArgumentException("The node is not the root of a tree");
+        }
+        if (last.parent != null) {
+            throw new IllegalArgumentException("The node is not the root of a tree");
+        }
         if (isLeaf()) {
             return last;
-        } else if (parent != null) {
-            throw new IllegalArgumentException("This is not the root of a tree");
         } else if (last.isLeaf()) {
             @SuppressWarnings("unchecked")
             N nThis = (N)this;
@@ -1112,6 +1116,7 @@ public abstract class RedBlackNode<N extends RedBlackNode<N>> implements Compara
      * The base class's implementation takes O(log N) time.  If a RedBlackNode subclass stores a value used to order the
      * nodes, then it could override compareTo to compare the nodes' values, which would take O(1) time.
      */
+    @Override
     public int compareTo(N other) {
         if (isLeaf() || other.isLeaf()) {
             throw new IllegalArgumentException("One of the nodes is a leaf node");
@@ -1325,7 +1330,7 @@ public abstract class RedBlackNode<N extends RedBlackNode<N>> implements Compara
      * useful for debugging.  RedBlackNode subclasses may want to override assertSubtreeIsValid() to call
      * assertOrderIsValid.
      * @param comparator A comparator indicating how the nodes should be ordered.  If this is null, we use the nodes'
-     *     natural order, as in N.compare.
+     *     natural order, as in N.compareTo.
      */
     public void assertOrderIsValid(Comparator<? super N> comparator) {
         if (comparator == null) {
diff --git a/src/com/github/btrekkie/sub_array_min/SubArrayMin.java b/src/com/github/btrekkie/sub_array_min/SubArrayMin.java
index 874db6575..63634c9f8 100644
--- a/src/com/github/btrekkie/sub_array_min/SubArrayMin.java
+++ b/src/com/github/btrekkie/sub_array_min/SubArrayMin.java
@@ -57,6 +57,9 @@ public class SubArrayMin {
 
         int min = Math.min(lca.value, Math.min(start.value, end.value));
         if (start != lca) {
+            if (start.right.min < min) {
+                min = start.right.min;
+            }
             for (SubArrayMinNode node = start; node.parent != lca; node = node.parent) {
                 if (node.parent.left == node) {
                     if (node.parent.value < min) {
@@ -69,6 +72,9 @@ public class SubArrayMin {
             }
         }
         if (end != lca) {
+            if (end.left.min < min) {
+                min = end.left.min;
+            }
             for (SubArrayMinNode node = end; node.parent != lca; node = node.parent) {
                 if (node.parent.right == node) {
                     if (node.parent.value < min) {
diff --git a/src/com/github/btrekkie/sub_array_min/test/SubArrayMinTest.java b/src/com/github/btrekkie/sub_array_min/test/SubArrayMinTest.java
index d69657f7a..a29719ddc 100644
--- a/src/com/github/btrekkie/sub_array_min/test/SubArrayMinTest.java
+++ b/src/com/github/btrekkie/sub_array_min/test/SubArrayMinTest.java
@@ -13,16 +13,16 @@ public class SubArrayMinTest {
         SubArrayMin sam = new SubArrayMin();
         sam.add(12);
         sam.add(42);
-        sam.add(16);
         sam.add(-3);
-        sam.add(8);
+        sam.add(16);
         sam.add(5);
+        sam.add(8);
         sam.add(4);
         assertEquals(-3, sam.min(0, 7));
-        assertEquals(12, sam.min(0, 3));
+        assertEquals(12, sam.min(0, 2));
         assertEquals(-3, sam.min(2, 4));
         assertEquals(12, sam.min(0, 1));
-        assertEquals(5, sam.min(4, 6));
+        assertEquals(5, sam.min(3, 6));
         assertEquals(4, sam.min(4, 7));
 
         sam = new SubArrayMin();