diff --git a/src/test/java/lambda/part3/exercise/Mapping.java b/src/test/java/lambda/part3/exercise/Mapping.java
index c0a814a..56ec252 100644
--- a/src/test/java/lambda/part3/exercise/Mapping.java
+++ b/src/test/java/lambda/part3/exercise/Mapping.java
@@ -32,8 +32,11 @@ public List<T> getList() {
         // [T] -> (T -> R) -> [R]
         // [T1, T2, T3] -> (T -> R) -> [R1, R2, R3]
         public <R> MapHelper<R> map(Function<T, R> f) {
-            // TODO
-            throw new UnsupportedOperationException();
+           final List<R> result = new ArrayList<>();
+           for (T element : list) {
+               result.add(f.apply(element));
+           }
+           return new MapHelper<>(result);
         }
 
         // [T] -> (T -> [R]) -> [R]
@@ -76,11 +79,9 @@ public void mapping() {
 
         final List<Employee> mappedEmployees =
                 new MapHelper<>(employees)
-                /*
-                .map(TODO) // change name to John .map(e -> e.withPerson(e.getPerson().withFirstName("John")))
-                .map(TODO) // add 1 year to experience duration .map(e -> e.withJobHistory(addOneYear(e.getJobHistory())))
-                .map(TODO) // replace qa with QA
-                * */
+                        .map(e -> e.withPerson(e.getPerson().withFirstName("John")))
+                        .map(e -> e.withJobHistory(addOneYear(e.getJobHistory())))
+                        .map(e -> e.withJobHistory(replaceQA(e.getJobHistory())))
                 .getList();
 
         final List<Employee> expectedResult =
@@ -108,10 +109,28 @@ public void mapping() {
         assertEquals(mappedEmployees, expectedResult);
     }
 
+    private List<JobHistoryEntry> replaceQA(List<JobHistoryEntry> jobHistory) {
+        return new MapHelper<>(jobHistory)
+                .map(j -> j.getPosition().equals("qa")
+                        ? j.withPosition("QA")
+                        : j.withPosition(j.getPosition()))
+                .getList();
+    }
+
+    private List<JobHistoryEntry> addOneYear(List<JobHistoryEntry> jobHistory) {
+        return new MapHelper<>(jobHistory)
+                .map(j -> j.withDuration(j.getDuration() + 1))
+                .getList();
+    }
+
 
     private static class LazyMapHelper<T, R> {
+        private List<T> list;
+        private Function<T, R> function;
 
         public LazyMapHelper(List<T> list, Function<T, R> function) {
+            this.list = list;
+            this.function = function;
         }
 
         public static <T> LazyMapHelper<T, T> from(List<T> list) {
@@ -119,15 +138,19 @@ public static <T> LazyMapHelper<T, T> from(List<T> list) {
         }
 
         public List<R> force() {
-            // TODO
-            throw new UnsupportedOperationException();
+            List<R> result = new ArrayList<>();
+            for (T element : list) {
+                result.add(function.apply(element));
+            }
+
+            return result;
         }
 
         public <R2> LazyMapHelper<T, R2> map(Function<R, R2> f) {
-            // TODO
-            throw new UnsupportedOperationException();
-        }
 
+            return new LazyMapHelper<>(list, (function.andThen(f)));
+
+        }
     }
 
     private static class LazyFlatMapHelper<T, R> {
@@ -165,8 +188,6 @@ public <R2> LazyFlatMapHelper<T, R2> flatMap(Function<R, List<R2>> f) {
         }
     }
 
-
-
     @Test
     public void lazy_mapping() {
         final List<Employee> employees =
@@ -193,6 +214,9 @@ public void lazy_mapping() {
 
         final List<Employee> mappedEmployees =
                 LazyMapHelper.from(employees)
+                        .map(e -> e.withPerson(e.getPerson().withFirstName("John")))
+                        .map(e->e.withJobHistory(addOneYear(e.getJobHistory())))
+                        .map(e ->e.withJobHistory(replaceQA(e.getJobHistory())))
                 /*
                 .map(TODO) // change name to John
                 .map(TODO) // add 1 year to experience duration