Feat: added content to Lesson13.java - James Capparell

lesson_13/maps_java/maps_app/src/main/java/com/codedifferently/lesson13/Lesson13.java

@@ -1,12 +1,25 @@
 package com.codedifferently.lesson13;
 
+import java.util.HashMap;
+
 public class Lesson13 {
 
-  /**
-   * Provide the solution to LeetCode 3146 here:
-   * https://leetcode.com/problems/permutation-difference-between-two-strings
-   */
   public int findPermutationDifference(String s, String t) {
-    return 0;
+    HashMap<Character, Integer> stringS = new HashMap<>();
+    HashMap<Character, Integer> stringT = new HashMap<>();
+    int diffSum = 0;
+    for (int i = 0; i < t.length(); i++) {
+      stringS.put(s.charAt(i), i);
+      stringT.put(t.charAt(i), i);
+    }
+    for (Character key : stringS.keySet()) {
+      if (stringT.containsKey(key)) {
+        int value1 = stringS.get(key);
+        int value2 = stringT.get(key);
+        int difference = Math.abs(value1 - value2);
+        diffSum += difference;
+      }
+    }
+    return diffSum;
   }
 }

lesson_13/maps_ts/src/lesson13.ts

@@ -1,7 +1,20 @@
-/**
- * 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 stringS = new Map<string, number>();
+  const stringT = new Map<string, number>();
+  let diffSum = 0;
+  for (let i = 0; i < t.length; i++) {
+    stringS.set(s.charAt(i), i);
+    stringT.set(t.charAt(i), i);
+  }
+  for (const key of stringS.keys()) {
+    if (stringT.has(key)) {
+      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      const value1 = stringS.get(key)!; // Non-null assertion because we checked with has()
+      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      const value2 = stringT.get(key)!; // Non-null assertion
+      const difference = Math.abs(value1 - value2);
+      diffSum += difference;
+    }
+  }
+  return diffSum;
+}