diff --git a/lesson_11/arrays_java/arrays_app/src/main/java/com/codedifferently/lesson11/Lesson11.java b/lesson_11/arrays_java/arrays_app/src/main/java/com/codedifferently/lesson11/Lesson11.java
index 248938a96..ac3787485 100644
--- a/lesson_11/arrays_java/arrays_app/src/main/java/com/codedifferently/lesson11/Lesson11.java
+++ b/lesson_11/arrays_java/arrays_app/src/main/java/com/codedifferently/lesson11/Lesson11.java
@@ -1,22 +1,31 @@
 package com.codedifferently.lesson11;
 
+import java.util.ArrayList;
 import java.util.List;
 
 public class Lesson11 {
 
-  /**
-   * Provide the solution to LeetCode 1929 here:
-   * https://leetcode.com/problems/concatenation-of-array
-   */
   public int[] getConcatenation(int[] nums) {
-    return null;
+    int n = nums.length;
+
+    int[] ans = new int[2 * n];
+
+    for (int i = 0; i < n; i++) {
+      ans[i] = nums[i];
+      ans[i + n] = nums[i];
+    }
+
+    return ans;
   }
 
-  /**
-   * Provide the solution to LeetCode 2942 here:
-   * https://leetcode.com/problems/find-words-containing-character/
-   */
   public List<Integer> findWordsContaining(String[] words, char x) {
-    return null;
+    List<Integer> indices = new ArrayList<>();
+
+    for (int i = 0; i < words.length; i++) {
+      if (words[i].indexOf(x) >= 0) {
+        indices.add(i);
+      }
+    }
+    return indices;
   }
 }