Solution

pom.xml

@@ -9,8 +9,8 @@
     <version>1.0-SNAPSHOT</version>
 
     <properties>
-        <maven.compiler.source>23</maven.compiler.source>
-        <maven.compiler.target>23</maven.compiler.target>
+        <maven.compiler.source>21</maven.compiler.source>
+        <maven.compiler.target>21</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <dependencies>

src/main/java/org/example/ConditionalExercises.java

@@ -4,14 +4,25 @@ public class ConditionalExercises {
     public boolean lessThanFive(int x) {
         // Replace the line below with code that returns true if x is less than 5, and false otherwise
         // (use an if statement with an else block.)
-        return false;
+        if (x<5) {
+            return true;
+        } else {
+            return false;
+        }
+//        return x < 5;
     }
 
     public String getAgeGroup(int age) {
         // Replace the line below with code that returns "child" if age is less than 13,
         // "teen" if age is less than 20, and "adult" otherwise
         // (use if, else if, and else)
-        return "";
+        if (age >= 20) {
+            return "adult";
+        } else if (age >= 13) {
+            return "teen";
+        } else {
+            return "child";
+        }
     }
 
     public boolean isValidPassword(String password) {
@@ -20,6 +31,10 @@ public boolean isValidPassword(String password) {
         // Replace the line below with code that returns true if password is at least 8 characters long
         // and false otherwise
         // (use an if statement with an else block.)
-        return false;
+        if (passwordLength < 8) {
+            return false;
+        } else {
+            return true;
+        }
     }
 }

src/main/java/org/example/LoopExercises.java

@@ -4,13 +4,42 @@ public class LoopExercises {
     public int sum(int n) {
         // Replace the line below with code that returns the sum of the numbers from 1 to n
         // (use a for loop)
-        return 0;
+        int total = 0;
+        for (int i = 1; i <= n; i++) {
+            total += i;
+        }
+        return total;
     }
 
     public int sumUntilEven(int n) {
         // Replace the line below with code that returns the sum of the numbers from 1 to n
         // but stops adding when the sum is even
         // (use a while loop with a sum variable and a counter variable)
-        return 0;
+        int sum = 0;
+        int i = 1;
+        while (i<=n) {
+            sum += i;
+            if (sum % 2 == 0) {
+                break;
+            }
+            i++;
+        }
+        return sum;
+    }
+
+    public int sumBackwardsUntilEven(int n) {
+        // Replace the line below with code that returns the sum of the numbers from 1 to n
+        // but stops adding when the sum is even
+        // (use a while loop with a sum variable and a counter variable)
+        int sum = 0;
+        int i = n;
+        while (i > 0) {
+            sum += i;
+            if (sum % 2 == 0) {
+                break;
+            }
+            i++;
+        }
+        return sum;
     }
 }

src/test/java/LoopExercisesTests.java

@@ -17,4 +17,12 @@ public void testSumUntilEven() {
         assert loopExercises.sumUntilEven(10) == 6;
         assert loopExercises.sumUntilEven(100) == 6;
     }
+
+    @Test
+    public void testSumBackwardsUntilEven() {
+        LoopExercises loopExercises = new LoopExercises();
+        assert loopExercises.sumBackwardsUntilEven(39) == 120;
+        assert loopExercises.sumBackwardsUntilEven(97) == 294;
+        assert loopExercises.sumBackwardsUntilEven(241) == 726;
+    }
 }