Merge pull request #107 from Joshua-Lu/patch-24

更新 0112.路径总和 Java版本

problems/0112.路径总和.md

@@ -305,25 +305,34 @@ public:
 
 
 Java：
-```java
+```Java
 class Solution {
-    private boolean flag = false;
    public boolean hasPathSum(TreeNode root, int targetSum) {
-        has_2(root,targetSum);
+        if (root == null) {
-        return flag;
+            return false;
         }
-
+        targetSum -= root.val;
-    public void has_2 (TreeNode root, int count) {
+        // 叶子结点
-        if (root == null) return;
+        if (root.left == null && root.right == null) {
-        if (root.left == null && root.right == null && count == root.val) {
+            return targetSum == 0;
-            flag = true;
         }
-        if (root.left != null) has_2(root.left,count - root.val);
+        if (root.left != null) {
-        if (root.right != null) has_2(root.right,count - root.val);
+            boolean left = hasPathSum(root.left, targetSum);
+            if (left) {// 已经找到
+                return true;
+            }
+        }
+        if (root.right != null) {
+            boolean right = hasPathSum(root.right, targetSum);
+            if (right) {// 已经找到
+                return true;
+            }
+        }
+        return false;
     }
 }
-```
 
+```
 
 Python：