0020有效的括号 Java更简单易懂的新解法

problems/0020.有效的括号.md

@@ -172,6 +172,29 @@ class Solution {
 }
 ```
 
+```java
+// 解法二
+// 对应的另一半一定在栈顶
+class Solution {
+    public boolean isValid(String s) {
+        Stack<Character> stack = new Stack<>();
+        for(char c : s.toCharArray()){
+            // 有对应的另一半就直接消消乐
+            if(c == ')' && !stack.isEmpty() && stack.peek() == '(')
+                stack.pop();
+            else if(c == '}' && !stack.isEmpty() && stack.peek() == '{')
+                stack.pop();
+            else if(c == ']' && !stack.isEmpty() && stack.peek() == '[')
+                stack.pop();
+            else
+                stack.push(c);// 没有匹配的就放进去
+        }
+
+        return stack.isEmpty();
+    }
+}
+```
+
 ### Python：
 
 ```python