add 1469

fishercoder1534 · fishercoder1534 · commit 5bb0c043bb6f · 2020-07-22T17:05:18.000-07:00
diff --git a/README.md b/README.md
@@ -26,6 +26,7 @@ _If you like this project, please leave me a star._ &#9733;
 |1475|[Final Prices With a Special Discount in a Shop](https://leetcode.com/problems/final-prices-with-a-special-discount-in-a-shop/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1475.java) | |Easy|Array|
 |1471|[The k Strongest Values in an Array](https://leetcode.com/problems/the-k-strongest-values-in-an-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1471.java) | |Medium|Array, Sort|
 |1470|[Shuffle the Array](https://leetcode.com/problems/shuffle-the-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1470.java), [C++](../master/cpp/_1470.cpp) | |Easy|Array|
+|1469|[Find All The Lonely Nodes](https://leetcode.com/problems/find-all-the-lonely-nodes/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1469.java) | |Easy|Tree, DFS|
 |1466|[Reorder Routes to Make All Paths Lead to the City Zero](https://leetcode.com/problems/reorder-routes-to-make-all-paths-lead-to-the-city-zero/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1466.java) | |Medium|Tree, DFS|
 |1464|[Maximum Product of Two Elements in an Array](https://leetcode.com/problems/maximum-product-of-two-elements-in-an-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1464.java) | |Easy|Array|
 |1460|[Make Two Arrays Equal by Reversing Sub-arrays](https://leetcode.com/problems/make-two-arrays-equal-by-reversing-sub-arrays/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1460.java) | |Easy|Array|
diff --git a/src/main/java/com/fishercoder/solutions/_1469.java b/src/main/java/com/fishercoder/solutions/_1469.java
@@ -0,0 +1,33 @@
+package com.fishercoder.solutions;
+
+import com.fishercoder.common.classes.TreeNode;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class _1469 {
+    public static class Solution1 {
+        public List<Integer> getLonelyNodes(TreeNode root) {
+            List<Integer> lonelyNodes = new ArrayList<>();
+            dfs(root, lonelyNodes);
+            return lonelyNodes;
+        }
+
+        private void dfs(TreeNode root, List<Integer> lonelyNodes) {
+            if (root == null) {
+                return;
+            }
+
+            if (root.left == null && root.right != null) {
+                lonelyNodes.add(root.right.val);
+            }
+
+            if (root.left != null && root.right == null) {
+                lonelyNodes.add(root.left.val);
+            }
+
+            dfs(root.left, lonelyNodes);
+            dfs(root.right, lonelyNodes);
+        }
+    }
+}
diff --git a/src/test/java/com/fishercoder/_1469Test.java b/src/test/java/com/fishercoder/_1469Test.java
@@ -0,0 +1,30 @@
+package com.fishercoder;
+
+import com.fishercoder.common.utils.TreeUtils;
+import com.fishercoder.solutions._1469;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.util.Arrays;
+
+import static junit.framework.TestCase.assertEquals;
+
+public class _1469Test {
+    private static _1469.Solution1 solution1;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _1469.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        assertEquals(Arrays.asList(4), solution1.getLonelyNodes(TreeUtils.constructBinaryTree(Arrays.asList(1, 2, 3, null, 4))));
+    }
+
+    @Test
+    public void test2() {
+        assertEquals(Arrays.asList(6, 2), solution1.getLonelyNodes(TreeUtils.constructBinaryTree(Arrays.asList(7, 1, 4, 6, null, 5, 3, null, null, null, null, null, 2))));
+    }
+
+}
