diff --git a/main.cpp b/main.cpp
index add1041..52ecdef 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,6 +1,8 @@
 #include <map>
 #include <string>
 
+// L4: Function.
+
 std::map<int, int> memory_generateConstPlayfield(
   int n
 ) {
@@ -15,6 +17,8 @@ std::map<int, int> memory_generateConstPlayfield(
   return idGroups;
 }
 
+// L20: Test.
+
 std::string test_memory_generateConstPlayfield() {
   auto idGroups = memory_generateConstPlayfield(2);
   if (
@@ -26,10 +30,11 @@ std::string test_memory_generateConstPlayfield() {
   ) {
     return "OK: memory_generateConstPlayfield";
   }
-
   return "ERR: memory_generateConstPlayfield";
 }
 
+// L36: Run.
+
 int main() {
   printf("%s\n", test_memory_generateConstPlayfield().c_str());
 }
diff --git a/main.js b/main.js
index ca8a4b4..a21ebeb 100644
--- a/main.js
+++ b/main.js
@@ -1,6 +1,8 @@
 
 
 
+// L4: Function.
+
 function memory_generateConstPlayfield(
   n
 ) {
@@ -12,10 +14,11 @@ function memory_generateConstPlayfield(
     idGroups[id] = gid;
     id += 1;
   }
-
   return idGroups;
 }
 
+// L20: Test.
+
 function test_memory_generateConstPlayfield() {
   let idGroups = memory_generateConstPlayfield(2)
   if (
@@ -27,8 +30,9 @@ function test_memory_generateConstPlayfield() {
   ) {
     return "OK: memory_generateConstPlayfield"
   }
-
   return "ERR: memory_generateConstPlayfield"
 }
 
+// L36: Run.
+
 console.log(test_memory_generateConstPlayfield())
diff --git a/main.swift b/main.swift
index 448287a..3a584d8 100644
--- a/main.swift
+++ b/main.swift
@@ -1,6 +1,8 @@
 
 
 
+// L4: Function
+
 func memory_generateConstPlayfield(
   _ n: Int
 ) -> [Int: Int] {
@@ -12,10 +14,11 @@ func memory_generateConstPlayfield(
     idGroups[id] = gid
     id += 1
   }
-
   return idGroups
 }
 
+// L20: Test.
+
 func test_memory_generateConstPlayfield() -> String {
   let idGroups = memory_generateConstPlayfield(2)
   if (
@@ -27,8 +30,9 @@ func test_memory_generateConstPlayfield() -> String {
   ) {
     return "OK: memory_generateConstPlayfield"
   }
-
   return "ERR: memory_generateConstPlayfield"
 }
 
+// L36: Run.
+
 print(test_memory_generateConstPlayfield())