Complete

src/main/java/BonusExercises.java

@@ -39,7 +39,21 @@ public class BonusExercises {
         If no match for a date is found in the string, return null.
     */
     public String findDate(String string) {
-        // todo
+        String regex1 = "\\d{4}[-/](0[1-9]|1[0-2])[-/](0[1-9]|[12]\\d|3[01])";
+        String regex2 = "(0[1-9]|[12]\\d|3[01])/(0[1-9]|1[0-2])/\\d{4}";
+
+        Pattern pattern1 = Pattern.compile(regex1);
+        Pattern pattern2 = Pattern.compile(regex2);
+        Matcher matcher1 = pattern1.matcher(string);
+        Matcher matcher2 = pattern2.matcher(string);
+
+        if (matcher1.find()) {
+            return matcher1.group();
+        }
+
+        if (matcher2.find()) {
+            return matcher2.group();
+        }
         return null;
     }
 
@@ -54,8 +68,42 @@ public class BonusExercises {
         - has no white-space in it
      */
     public int findValidPasswords(String string) {
-        // todo
-        return -1;
+        int count = 0;
+        String[] parts = string.split(" ");
+
+        for (String p : parts) {
+            if (p.length() < 8) {
+                continue;
+            }
+            boolean hasUpper = false;
+            boolean hasLower = false;
+            boolean hasNumber = false;
+            boolean hasSpecial = false;
+            boolean hasSpace = false;
+
+            for (int i = 0; i < p.length(); i++) {
+                char c = p.charAt(i);
+                if (Character.isUpperCase(c)) {
+                    hasUpper = true;
+                }
+                else if (Character.isLowerCase(c)) {
+                    hasLower = true;
+                }
+                else if (Character.isDigit(c)) {
+                    hasNumber = true;
+                }
+                else if (Character.isWhitespace(c)) {
+                    hasSpace = true;
+                }
+                else {
+                    hasSpecial = true;
+                }
+            }
+            if (!hasSpace && hasUpper && hasLower && hasNumber && hasSpecial) {
+                count++;
+            }
+        }
+        return count;
     }
 
     /*
@@ -66,7 +114,18 @@ public class BonusExercises {
      */
     public List<String> findPalindromes(String string) {
         List<String> list = new ArrayList<>();
-        // todo
+        String[] words = string.split(" ");
+
+        for (String w : words) {
+            String clean = w.replaceAll("[^A-Za-z]", "");
+            if (clean.length() >= 3) {
+                String lower = clean.toLowerCase() ;
+                String reversed = new StringBuilder(lower).reverse().toString();
+                if (lower.equals(reversed)) {
+                    list.add(clean);
+                }
+            }
+        }
         return list;
     }