feat: add python and java solutions to leetcode problem: No.0246

Author: yanglbme

solution/0200-0299/0246.Strobogrammatic Number/README.md

@@ -44,15 +44,55 @@
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```python
-
+class Solution:
+    def isStrobogrammatic(self, num: str) -> bool:
+        def match(a, b):
+            if a in {'0', '1', '8'}:
+                return a == b
+            if a == '6':
+                return b == '9'
+            if a == '9':
+                return b == '6'
+            return False
+        n = len(num)
+        i, j = 0, n - 1
+        while i <= j:
+            if not match(num[i], num[j]):
+                return False
+            i += 1
+            j -= 1
+        return True
 ```
 
 ### **Java**
 
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```java
-
+class Solution {
+    public boolean isStrobogrammatic(String num) {
+        int n = num.length();
+        for (int i = 0, j = n - 1; i <= j; ++i, --j) {
+            if (!match(num.charAt(i), num.charAt(j))) return false;
+        }
+        return true;
+    }
+
+    private boolean match(char a, char b) {
+        switch (a) {
+            case '0':
+            case '1':
+            case '8':
+                return a == b;
+            case '6':
+                return b == '9';
+            case '9':
+                return b == '6';
+            default:
+                return false;
+        }
+    }
+}
 ```
 
 ### **...**

solution/0200-0299/0246.Strobogrammatic Number/README_EN.md

@@ -30,13 +30,53 @@
 ### **Python3**
 
 ```python
-
+class Solution:
+    def isStrobogrammatic(self, num: str) -> bool:
+        def match(a, b):
+            if a in {'0', '1', '8'}:
+                return a == b
+            if a == '6':
+                return b == '9'
+            if a == '9':
+                return b == '6'
+            return False
+        n = len(num)
+        i, j = 0, n - 1
+        while i <= j:
+            if not match(num[i], num[j]):
+                return False
+            i += 1
+            j -= 1
+        return True
 ```
 
 ### **Java**
 
 ```java
-
+class Solution {
+    public boolean isStrobogrammatic(String num) {
+        int n = num.length();
+        for (int i = 0, j = n - 1; i <= j; ++i, --j) {
+            if (!match(num.charAt(i), num.charAt(j))) return false;
+        }
+        return true;
+    }
+
+    private boolean match(char a, char b) {
+        switch (a) {
+            case '0':
+            case '1':
+            case '8':
+                return a == b;
+            case '6':
+                return b == '9';
+            case '9':
+                return b == '6';
+            default:
+                return false;
+        }
+    }
+}
 ```
 
 ### **...**

solution/0200-0299/0246.Strobogrammatic Number/Solution.java

@@ -1,26 +1,24 @@
 class Solution {
     public boolean isStrobogrammatic(String num) {
-        if (num == null || num.length() == 0) {
-            return false;
+        int n = num.length();
+        for (int i = 0, j = n - 1; i <= j; ++i, --j) {
+            if (!match(num.charAt(i), num.charAt(j))) return false;
         }
-        Map<Character, Character> map = new HashMap<>();
-        map.put('0', '0');
-        map.put('1', '1');
-        map.put('6', '9');
-        map.put('9', '6');
-        map.put('8', '8');
-        if (num.length() == 1) {
-            return "1".equals(num) || "8".equals(num) || "0".equals(num);
-        }
-        char[] chars = num.toCharArray();
-        for (int i = 0; i < chars.length; i++) {
-            if (!map.containsKey(chars[i])) {
-                return false;
-            }
-            if (chars[chars.length - 1 - i] != map.get(chars[i])) {
+        return true;
+    }
+
+    private boolean match(char a, char b) {
+        switch (a) {
+            case '0':
+            case '1':
+            case '8':
+                return a == b;
+            case '6':
+                return b == '9';
+            case '9':
+                return b == '6';
+            default:
                 return false;
-            }
         }
-        return true;
     }
 }

solution/0200-0299/0246.Strobogrammatic Number/Solution.py

@@ -0,0 +1,18 @@
+class Solution:
+    def isStrobogrammatic(self, num: str) -> bool:
+        def match(a, b):
+            if a in {'0', '1', '8'}:
+                return a == b
+            if a == '6':
+                return b == '9'
+            if a == '9':
+                return b == '6'
+            return False
+        n = len(num)
+        i, j = 0, n - 1
+        while i <= j:
+            if not match(num[i], num[j]):
+                return False
+            i += 1
+            j -= 1
+        return True