diff --git a/solution/0600-0699/0670.Maximum Swap/README.md b/solution/0600-0699/0670.Maximum Swap/README.md
index aa5d2d0bdefd9ed608bc6e1c04d6c3e59cb8548d..a3c7b209217cf800b77ed88ed391d6d593d636f8 100644
--- a/solution/0600-0699/0670.Maximum Swap/README.md	
+++ b/solution/0600-0699/0670.Maximum Swap/README.md	
@@ -49,6 +49,19 @@
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```java
+char[] cnum = String.valueOf(num).toCharArray();
+        
+        for(int i = 0; i < cnum.length; i ++){
+            for(int j = i + 1; j < cnum.length; j ++){
+                if((cnum[i] + cnum[j]) % 2 == 0 && cnum[j] > cnum[i]){
+                    // 交换两数
+                    cnum[i] ^= cnum[j];
+                    cnum[j] ^= cnum[i];
+                    cnum[i] ^= cnum[j];
+                }
+            }
+        }
+        return Integer.valueOf(new String(cnum));
 
 ```