diff --git a/lesson_13/maps_java/maps_app/src/main/java/com/codedifferently/lesson13/Lesson13.java b/lesson_13/maps_java/maps_app/src/main/java/com/codedifferently/lesson13/Lesson13.java
index 0c981abbf..89f09c098 100644
--- a/lesson_13/maps_java/maps_app/src/main/java/com/codedifferently/lesson13/Lesson13.java
+++ b/lesson_13/maps_java/maps_app/src/main/java/com/codedifferently/lesson13/Lesson13.java
@@ -1,12 +1,18 @@
 package com.codedifferently.lesson13;
 
-public class Lesson13 {
+import java.util.HashMap;
 
-  /**
-   * Provide the solution to LeetCode 3146 here:
-   * https://leetcode.com/problems/permutation-difference-between-two-strings
-   */
+public class Lesson13 {
   public int findPermutationDifference(String s, String t) {
-    return 0;
+    HashMap<Character, Integer> hashMap = new HashMap<>();
+    int permDifferences = 0;
+    for (int i = 0; i < s.length(); i++) {
+      hashMap.put(s.charAt(i), i);
+    }
+    for (char key : hashMap.keySet()) {
+      int indexInT = t.indexOf(Character.toString(key));
+      permDifferences += Math.abs(s.indexOf(key) - indexInT);
+    }
+    return permDifferences;
   }
 }
diff --git a/lesson_13/maps_ts/src/lesson13.ts b/lesson_13/maps_ts/src/lesson13.ts
index 5207487e2..f9a6b9e8b 100644
--- a/lesson_13/maps_ts/src/lesson13.ts
+++ b/lesson_13/maps_ts/src/lesson13.ts
@@ -1,7 +1,14 @@
-/**
- * Provide the solution to LeetCode 3146 here:
- * https://leetcode.com/problems/permutation-difference-between-two-strings
- */
+
 export function findPermutationDifference(s: string, t: string): number {
-  return 0;
-}
+  const map = new Map<string,number>();
+    for (let i = 0; i < s.length; i++) {
+      map.set(s.charAt(i), i);
+    }
+    let permDifferences = 0;
+    for (const key of map.keys()) {
+      const indexInT = t.indexOf(String(key));
+       permDifferences += Math.abs(s.indexOf(key) - indexInT);
+    }
+    return permDifferences;
+  }
+