add 1448

Author: fishercoder1534

README.md

@@ -8,6 +8,7 @@ _If you like this project, please leave me a star._ ★
 
 |  #  |      Title     |   Solutions   | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|--------|-------------|-------------
+|1448|[Count Good Nodes in Binary Tree](https://leetcode.com/problems/count-good-nodes-in-binary-tree/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1448.java) | |Medium|Tree, DFS|
 |1447|[Simplified Fractions](https://leetcode.com/problems/simplified-fractions/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1447.java) | |Medium|Math|
 |1446|[Consecutive Characters](https://leetcode.com/problems/consecutive-characters/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1446.java) | |Easy|String|
 |1441|[Build an Array With Stack Operations](https://leetcode.com/problems/build-an-array-with-stack-operations/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1441.java) | |Easy|Stack|

src/main/java/com/fishercoder/solutions/_1448.java

@@ -0,0 +1,34 @@
+package com.fishercoder.solutions;
+
+import com.fishercoder.common.classes.TreeNode;
+
+import java.util.Collections;
+import java.util.PriorityQueue;
+
+public class _1448 {
+    public static class Solution1 {
+        int count;
+
+        public int goodNodes(TreeNode root) {
+            dfs(root, new PriorityQueue<>(Collections.reverseOrder()));
+            return count;
+        }
+
+        private void dfs(TreeNode root, PriorityQueue<Integer> maxHeap) {
+            if (root == null) {
+                return;
+            }
+            maxHeap.offer(root.val);
+            if (root.val >= maxHeap.peek()) {
+                count++;
+            }
+            if (root.left != null) {
+                dfs(root.left, maxHeap);
+            }
+            if (root.right != null) {
+                dfs(root.right, maxHeap);
+            }
+            maxHeap.remove(root.val);
+        }
+    }
+}

src/test/java/com/fishercoder/_1448Test.java

@@ -0,0 +1,51 @@
+package com.fishercoder;
+
+import com.fishercoder.common.classes.TreeNode;
+import com.fishercoder.common.utils.TreeUtils;
+import com.fishercoder.solutions._1448;
+import org.junit.Test;
+
+import java.util.Arrays;
+
+import static org.junit.Assert.assertEquals;
+
+public class _1448Test {
+    private static _1448.Solution1 solution1;
+    private static TreeNode root;
+
+    @Test
+    public void test1() {
+        solution1 = new _1448.Solution1();
+        root = TreeUtils.constructBinaryTree(Arrays.asList(3, 1, 4, 3, null, 1, 5));
+        assertEquals(4, solution1.goodNodes(root));
+    }
+
+    @Test
+    public void test2() {
+        solution1 = new _1448.Solution1();
+        root = TreeUtils.constructBinaryTree(Arrays.asList(3, 3, null, 4, 2));
+        assertEquals(3, solution1.goodNodes(root));
+    }
+
+    @Test
+    public void test3() {
+        solution1 = new _1448.Solution1();
+        root = TreeUtils.constructBinaryTree(Arrays.asList(1));
+        assertEquals(1, solution1.goodNodes(root));
+    }
+
+    @Test
+    public void test4() {
+        solution1 = new _1448.Solution1();
+        root = TreeUtils.constructBinaryTree(Arrays.asList(2, null, 4, 10, 8, null, null, 4));
+        assertEquals(4, solution1.goodNodes(root));
+    }
+
+    @Test
+    public void test5() {
+        solution1 = new _1448.Solution1();
+        root = TreeUtils.constructBinaryTree(Arrays.asList(9, null, 3, 6));
+        assertEquals(1, solution1.goodNodes(root));
+    }
+
+}