更新了第202，242，349题

problems/0202.快乐数.md

@@ -84,7 +84,28 @@ public:
 
 
 Java：
+```java
+class Solution {
+    public boolean isHappy(int n) {
+        Set<Integer> record = new HashSet<>();
+        while (n != 1 && !record.contains(n)) {
+            record.add(n);
+            n = getNextNumber(n);
+        }
+        return n == 1;
+    }
 
+    private int getNextNumber(int n) {
+        int res = 0;
+        while (n > 0) {
+            int temp = n % 10;
+            res += temp * temp;
+            n = n / 10;
+        }
+        return res;
+    }
+}
+```
 
 Python：
 

problems/0242.有效的字母异位词.md

@@ -86,7 +86,8 @@ public:
 
 Java：
 ```java
-public boolean isAnagram(String s, String t) {
+class Solution {
+    public boolean isAnagram(String s, String t) {
         int[] record = new int[26];
         for (char c : s.toCharArray()) {
             record[c - 'a'] += 1;
@@ -100,8 +101,8 @@ public boolean isAnagram(String s, String t) {
             }
         }
         return true;
+    }
 }
-
 ```
 
 Python：

problems/0349.两个数组的交集.md

@@ -75,7 +75,31 @@ public:
 
 
 Java：
+```java
+class Solution {
+    public int[] intersection(int[] nums1, int[] nums2) {
+        Set<Integer> record = new HashSet<Integer>();
+        Set<Integer> unique = new HashSet<Integer>();
 
+        for (int num : nums1) {
+            record.add(num);
+        }
+
+        for (int num : nums2) {
+            if (record.contains(num)) {
+                unique.add(num);
+            }
+        }
+
+        int[] res = new int[unique.size()];
+        int index = 0;
+        for (int num : unique) {
+            res[index++] = num;
+        }
+        return res;
+    }
+}
+```
 
 Python：