Finished set-practice

src/CommonElementsFinder.java

@@ -1,3 +1,4 @@
+import java.util.HashSet;
 import java.util.Set;
 
 /**
@@ -15,7 +16,21 @@ public class CommonElementsFinder {
      */
     public static Set<Integer> findCommonElements(int[] array1, int[] array2) {
         // TODO
-        return null;
+        Set<Integer> hash1 = new HashSet<>();
+        for (Integer integer : array1) {
+            hash1.add(integer);
+        }
+        Set<Integer> hash2 = new HashSet<>();
+        for (Integer integer : array2) {
+            hash2.add(integer);
+        }
+        Set<Integer> commonHash = new HashSet<>();
+        for (Integer integer : hash2) {
+            if (hash1.contains(integer)) {
+                commonHash.add(integer);
+            }
+        }
+        return commonHash;
     }
 
 

src/DuplicateRemover.java

@@ -1,4 +1,7 @@
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Set;
+import java.util.TreeSet;
 
 /**
  * The DuplicateRemover class provides a method to remove duplicate words
@@ -14,8 +17,16 @@ public class DuplicateRemover {
      * @return a sorted List<String> containing unique words from the input array
      */
     public static List<String> sortAndRemoveDuplicates(String[] words) {
-        // TODO
-        return null;
+        Set<String> unique = new TreeSet<>();
+        for(String word : words){
+            unique.add(word);
+        }
+        List<String> wordList = new ArrayList<>();
+        for(String word : unique){
+            wordList.add(word);
+        }
+        return wordList;
+
     }
 
     public static void main(String[] args) {

src/UniqueCharacterChecker.java

@@ -1,3 +1,7 @@
+import java.util.HashSet;
+import java.util.Set;
+import java.util.TreeSet;
+
 /**
  * The UniqueCharacterChecker class provides a method to check if all characters
  * in a given word are unique.
@@ -14,7 +18,26 @@ public static boolean hasUniqueCharacters(String word) {
         // TODO: implement this!
         // Requirement: This must run in O(n) time, where n is the number of characters in the word
         // Hint: Stuck? Consider looking up "charAt" and seeing how it can help you
-        return false;
+
+        /*
+        hashset only unqiue values
+        try making a counter to see if it as been seen
+         loop through the word get its .length()
+
+         go through each of the letters and check to see if it has appeared more than once
+
+         return true or false whether there are duplicate characters
+         */
+        Set<Character> seen = new HashSet<>();
+        for (int i = 0; i < word.length(); i++) {
+            if (seen.contains(word.charAt(i))) {
+                return false;
+            }
+            seen.add(word.charAt(i));
+        }
+
+
+        return true;
     }
 
     public static void main(String[] args) {