Fix:#5502

Author: sujitgunjal

src/main/java/com/thealgorithms/dynamicprogramming/ArrayList.java

@@ -0,0 +1,5 @@
+package com.thealgorithms.dynamicprogramming;
+
+public class ArrayList<T> {
+
+}

src/main/java/com/thealgorithms/dynamicprogramming/subsetRecursion.java

@@ -0,0 +1,17 @@
+package com.thealgorithms.dynamicprogramming;
+import java.util.ArrayList;
+public class subsetRecursion {
+    public static void subset(String prefix, String str, ArrayList<String> result) {
+        // Base case: if the string is empty, add the prefix to the result
+        if (str.isEmpty()) {
+            result.add(prefix);
+            return;
+        }
+        // Recursive call by including the first character in the prefix
+        subset(prefix + str.charAt(0), str.substring(1), result);
+        
+        // Recursive call by excluding the first character
+        subset(prefix, str.substring(1), result);
+        
+    }
+}