diff --git a/v4/cli.cpp b/v4/cli.cpp
index 60aa279..153e423 100644
--- a/v4/cli.cpp
+++ b/v4/cli.cpp
@@ -7,24 +7,172 @@
 #include "memory_Context.h"
 #include "shell.h"
 
+// Exit
+//
+// Conditions:
+// 1. `e`, `exit`, `q`, or `quit` was entered
+// 2. Victory has just been reported
+memory_Context cli_exit(
+  memory_Context c
+) {
+  if (
+    c.recentField == "input" &&
+    (
+      c.input == "e" ||
+      c.input == "exit" ||
+      c.input == "q" ||
+      c.input == "quit"
+    )
+  ) {
+    c.exit = true;
+    c.recentField = "exit";
+    return c;
+  }
+  if (
+    c.recentField == "outputVictory"
+  ) {
+    c.exit = true;
+    c.recentField = "exit";
+    return c;
+  }
+  c.recentField = "none";
+  return c;
+}
+
+// Ask user to go on
+//
+// Conditions:
+// 1. Items have just matched and there are still items left to select
+memory_Context cli_goOn(
+  memory_Context c
+) {
+  if (
+    c.recentField == "outputMatchedItems" &&
+    c.hiddenItems.size() != c.playfieldItems.size()
+  ) {
+    c.outputGoOn = "Go on:";
+    c.recentField = "outputGoOn";
+    return c;
+  }
+  c.recentField = "none";
+  return c;
+}
+
 // Greet the user
-cli_Context cli_greetUser(
-  cli_Context c
+//
+// Conditions:
+// 1. Just launched
+memory_Context cli_greetUser(
+  memory_Context c
+) {
+  if (
+    c.recentField == "didLaunch" &&
+    c.didLaunch == true
+  ) {
+    c.outputGreeting = "OGS Memory Command Line Interface";
+    c.recentField = "outputGreeting";
+    return c;
+  }
+  c.recentField = "none";
+  return c;
+}
+
+// Ask user to select second item to have a pair of selected items
+//
+// Conditions:
+// 1. Single item has just been selected
+memory_Context cli_promptSecondItemSelection(
+  memory_Context c
 ) {
-  c.outputGreeting = "OGS Memory Textual UI";
-  c.recentField = "outputGreeting";
+  if (
+    c.recentField == "selectedItems" &&
+    c.selectedItems.size() == 1
+  ) {
+    c.outputPromptSelection = "Select the second item now:";
+    c.recentField = "outputPromptSelection";
+    return c;
+  }
+  c.recentField = "none";
+  return c;
+}
+
+// Report matched items
+//
+// Conditions:
+// 1. Items were hidden (i.e., they matched)
+memory_Context cli_reportMatchedItems(
+  memory_Context c
+) {
+  if (
+    c.recentField == "hiddenItems"
+  ) {
+    c.outputMatchedItems = "Items matched!";
+    c.recentField = "outputMatchedItems";
+    return c;
+  }
+  c.recentField = "none";
+  return c;
+}
+
+// Report victory
+memory_Context cli_reportVictory(
+  memory_Context c
+) {
+  if (
+    c.recentField == "victory"
+  ) {
+    c.outputVictory = "VICTORY! The game is over now";
+    c.recentField = "outputVictory";
+    return c;
+  }
+  c.recentField = "none";
+  return c;
+}
+
+// Select item
+//
+// Conditions:
+// 1. Id is digit
+memory_Context cli_selectItem(
+  memory_Context c
+) {
+  if (
+    c.recentField == "input" &&
+    c.input.isdigit()
+  ) {
+    // CLI ids start with 1 while memory module has ids starting with 0
+    // Convert CLI id to memory id
+    c.selectedId = int(c.input) - 1;
+    c.recentField = "selectedId";
+    return c;
+  }
+  c.recentField = "none";
   return c;
 }
 
 // Show help (aka commands)
-cli_Context cli_showHelp(
-  cli_Context c
+//
+// Conditions:
+// 1. Just launched
+// 1. `h` or `help` was entered
+memory_Context cli_showHelp(
+  memory_Context c
 ) {
   if (
-    c.input == "h" ||
-    c.input == "help"
+    (
+      c.recentField == "didLaunch" &&
+      c.didLaunch == true
+    ) ||
+    (
+      c.recentField == "input" &&
+      c.input == "h"
+    ) ||
+    (
+      c.recentField == "input" &&
+      c.input == "help"
+    )
   ) {
-    c.outputHelp = "Commands:\n\te, exit, q, quit\n\t\tExit\n\th, help\n\t\tList commands\n";
+    c.outputHelp = "Commands:\n\te, exit, q, quit\n\t\tExit\n\th, help\n\t\tList commands\n\t1, 2, 3, ...\n\t\tSelect item\nEnter your choice:";
     c.recentField = "outputHelp";
     return c;
   }
@@ -32,3 +180,41 @@ cli_Context cli_showHelp(
   return c;
 }
 
+// Report mismatched items
+memory_Context cli_reportMismatchedItems(
+  memory_Context c
+) {
+  if (
+    c.recentField == "mismatchedItems"
+  ) {
+    c.outputMismatchedItems = "Wrong! Try again:";
+    c.recentField = "outputMismatchedItems";
+    return c;
+  }
+  c.recentField = "none";
+  return c;
+}
+
+//// Report selection of invalid item ids
+////
+//// Conditions:
+//// 1. Index out of bounds: less than minimum
+//// 2. Index out of bounds: greater than maximum
+//// 3. Item is already hidden
+////@llm_by_value
+////def cli_shouldReportInvalidItemSelection(
+////  c: cli_Context
+////) -> cli_Context:
+////  if (
+////    c.recentField == "cMemory" and
+////    c.cMemory.recentField == "selectedItems" and
+////    len(c.cMemory.selectedItems) == 1
+////  ):
+////    c.outputPromptSelection = "Select the second item now:"
+////    c.recentField = "outputPromptSelection"
+////    return c
+////  //}
+////  c.recentField = "none"
+////  return c
+//////}
+
diff --git a/v4/cli_test.cpp b/v4/cli_test.cpp
index fe70680..092c719 100644
--- a/v4/cli_test.cpp
+++ b/v4/cli_test.cpp
@@ -7,9 +7,135 @@
 #include "memory_Context.h"
 #include "shell.h"
 
+std::string cli_test_exit_e(
+) {
+  auto c = memory_createContext();
+  c.input = "e";
+  c.recentField = "input";
+  c = cli_exit(c);
+  if (
+    c.recentField == "exit"
+  ) {
+    return "OK: cli_exit_e";
+  }
+  return "ERR: cli_exit_e";
+}
+
+std::string cli_test_exit_exit(
+) {
+  auto c = memory_createContext();
+  c.input = "exit";
+  c.recentField = "input";
+  c = cli_exit(c);
+  if (
+    c.recentField == "exit"
+  ) {
+    return "OK: cli_exit_exit";
+  }
+  return "ERR: cli_exit_e";
+}
+
+
+
+
+std::string cli_test_exit_victory(
+) {
+  auto c = memory_createContext();
+  c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
+  c = memory_generateConstPlayfield(c);
+  // Match the first pair of tiles.
+  c.input = "1";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c.input = "2";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = memory_hideMatchingItems(c);
+  // Match the second pair of tiles.
+  c.input = "3";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c.input = "4";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = memory_hideMatchingItems(c);
+  c = memory_detectVictory(c);
+  c = cli_reportVictory(c);
+  c = cli_exit(c);
+  if (
+    c.recentField == "exit"
+  ) {
+    return "OK: cli_exit_victory";
+  }
+  return "ERR: cli_exit_victory";
+}
+
+std::string cli_test_exit_q(
+) {
+  auto c = memory_createContext();
+  c.input = "q";
+  c.recentField = "input";
+  c = cli_exit(c);
+  if (
+    c.recentField == "exit"
+  ) {
+    return "OK: cli_exit_q";
+  }
+  return "ERR: cli_exit_q";
+}
+
+std::string cli_test_exit_quit(
+) {
+  auto c = memory_createContext();
+  c.input = "quit";
+  c.recentField = "input";
+  c = cli_exit(c);
+  if (
+    c.recentField == "exit"
+  ) {
+    return "OK: cli_exit_quit";
+  }
+  return "ERR: cli_exit_quit";
+}
+
+
+
+std::string cli_test_goOn(
+) {
+  auto c = memory_createContext();
+  c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
+  c = memory_generateConstPlayfield(c);
+  // Match the first pair of items.
+  c.input = "1";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c.input = "2";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = memory_hideMatchingItems(c);
+  c = cli_reportMatchedItems(c);
+  c = cli_goOn(c);
+  if (
+    c.recentField == "outputGoOn"
+  ) {
+    return "OK: cli_goOn";
+  }
+  return "ERR: cli_goOn";
+}
+
 std::string cli_test_greetUser(
 ) {
-  auto c = cli_createContext();
+  auto c = memory_createContext();
+  c.didLaunch = true;
+  c.recentField = "didLaunch";
   c = cli_greetUser(c);
   if (
     c.recentField == "outputGreeting"
@@ -19,10 +145,90 @@ std::string cli_test_greetUser(
   return "ERR: cli_greetUser";
 }
 
+std::string cli_test_promptSecondItemSelection(
+) {
+  auto c = memory_createContext();
+  c.input = "1";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = cli_promptSecondItemSelection(c);
+  if (
+    c.recentField == "outputPromptSelection"
+  ) {
+    return "OK: cli_promptSecondItemSelection";
+  }
+  return "ERR: cli_promptSecondItemSelection";
+}
+
+std::string cli_test_reportMatchedItems(
+) {
+  auto c = memory_createContext();
+  c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
+  c = memory_generateConstPlayfield(c);
+  c.input = "1";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c.input = "2";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = memory_hideMatchingItems(c);
+  c = cli_reportMatchedItems(c);
+  if (
+    c.recentField == "outputMatchedItems"
+  ) {
+    return "OK: cli_reportMatchedItems";
+  }
+  return "ERR: cli_reportMatchedItems";
+}
+
+std::string cli_test_reportMismatchedItems(
+) {
+  auto c = memory_createContext();
+  c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
+  c = memory_generateConstPlayfield(c);
+  c.input = "1";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c.input = "3";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = memory_detectMismatchedItems(c);
+  c = cli_reportMismatchedItems(c);
+  if (
+    c.recentField == "outputMismatchedItems"
+  ) {
+    return "OK: cli_reportMismatchedItems";
+  }
+  return "ERR: cli_reportMismatchedItems";
+}
+
+std::string cli_test_selectItem(
+) {
+  auto c = memory_createContext();
+  c.input = "1";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  if (
+    c.recentField == "selectedId" &&
+    c.selectedId == 0
+  ) {
+    return "OK: cli_selectItem";
+  }
+  return "ERR: cli_selectItem";
+}
+
 std::string cli_test_showHelp_h(
 ) {
-  auto c = cli_createContext();
+  auto c = memory_createContext();
   c.input = "h";
+  c.recentField = "input";
   c = cli_showHelp(c);
   if (
     c.recentField == "outputHelp"
@@ -34,8 +240,9 @@ std::string cli_test_showHelp_h(
 
 std::string cli_test_showHelp_help(
 ) {
-  auto c = cli_createContext();
+  auto c = memory_createContext();
   c.input = "help";
+  c.recentField = "input";
   c = cli_showHelp(c);
   if (
     c.recentField == "outputHelp"
@@ -45,3 +252,58 @@ std::string cli_test_showHelp_help(
   return "ERR: cli_showHelp_help";
 }
 
+
+
+
+std::string cli_test_reportVictory(
+) {
+  auto c = memory_createContext();
+  c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
+  c = memory_generateConstPlayfield(c);
+  // Match the first pair of tiles.
+  c.input = "1";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c.input = "2";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = memory_hideMatchingItems(c);
+  // Match the second pair of tiles.
+  c.input = "3";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c.input = "4";
+  c.recentField = "input";
+  c = cli_selectItem(c);
+  c = memory_selectItem(c);
+  c = memory_hideMatchingItems(c);
+  c = memory_detectVictory(c);
+  c = cli_reportVictory(c);
+  if (
+    c.recentField == "outputVictory"
+  ) {
+    return "OK: cli_reportVictory";
+  }
+  return "ERR: cli_reportVictory";
+}
+
+//def cli_test_shouldReportIvalidItemSelection_outOfBoundsMin(
+//) -> str:
+//  c = cli_createContext()
+//  c.cMemory = memory_createContext()
+//  c.input = "0"
+//  c = cli_selectItem(c)
+//  c = cli_shouldReportInvalidItemSelection(c)
+//  if (
+//    c.recentField == "outputInvalidItemSelection"
+//  ):
+//    return "OK: cli_shouldReportInvalidItemSelection"
+//  //}
+//  return "ERR: cli_shouldReportInvalidItemSelection"
+////}
+//
+
diff --git a/v4/memory.cpp b/v4/memory.cpp
index 0d5a54a..52fd4b6 100644
--- a/v4/memory.cpp
+++ b/v4/memory.cpp
@@ -7,52 +7,13 @@
 #include "memory_Context.h"
 #include "shell.h"
 
-////////////////
-// Client initiated input
-////////////////
-
-// Generate constant playfield
-memory_Context memory_generateConstPlayfield(
-  memory_Context c
-) {
-  std::map<int, int> idGroups = { };
-  auto id = 0;
-  for (auto gid = 0; gid < c.playfieldSize; ++gid) {
-    idGroups[id] = gid;
-    id += 1;
-    idGroups[id] = gid;
-    id += 1;
-  }
-  c.playfieldItems = idGroups;
-  c.recentField = "playfieldItems";
-  return c;
-}
-
-// Select item
-memory_Context memory_selectItem(
-  memory_Context c
-) {
-  if (
-    c.selectedItems.size() == 2
-  ) {
-    c.selectedItems.clear();
-  }
-  c.selectedItems.push_back(c.selectedId);
-  c.recentField = "selectedItems";
-  return c;
-}
-
-////////////////
-// System initiated reaction
-////////////////
-
-// Deselect mismatched items
+// Detect mismatched items
 //
 // Conditions:
 // 0. Two items has just been selected
 // 1. The same item has been selected twice
 // 2. Selected items are of different groups
-memory_Context memory_shouldDeselectMismatchedItems(
+memory_Context memory_detectMismatchedItems(
   memory_Context c
 ) {
   if (!(
@@ -87,7 +48,7 @@ memory_Context memory_shouldDeselectMismatchedItems(
 //
 // Conditions:
 // 1. Matching items have just been hidden and all items are hidden now
-memory_Context memory_shouldDetectVictory(
+memory_Context memory_detectVictory(
   memory_Context c
 ) {
   if (
@@ -102,11 +63,40 @@ memory_Context memory_shouldDetectVictory(
   return c;
 }
 
+// Generate constant playfield
+//
+// Conditions:
+// 1. Size has just been specified
+//
+// Both ids and group ids start with 0
+
+memory_Context memory_generateConstPlayfield(
+  memory_Context c
+) {
+  if (!(
+    c.recentField == "playfieldSize"
+  )) {
+    c.recentField = "none";
+    return c;
+  }
+  std::map<int, int> idGroups = { };
+  auto id = 0;
+  for (auto gid = 0; gid < c.playfieldSize; ++gid) {
+    idGroups[id] = gid;
+    id += 1;
+    idGroups[id] = gid;
+    id += 1;
+  }
+  c.playfieldItems = idGroups;
+  c.recentField = "playfieldItems";
+  return c;
+}
+
 // Hide matching selected items
 //
 // Conditions:
 // 1. Two items are selected and they are of the same group
-memory_Context memory_shouldHideMatchingItems(
+memory_Context memory_hideMatchingItems(
   memory_Context c
 ) {
   if (
@@ -123,3 +113,28 @@ memory_Context memory_shouldHideMatchingItems(
   return c;
 }
 
+// Select item
+//
+// Conditions:
+// 1. Id has just been specified for selection
+
+memory_Context memory_selectItem(
+  memory_Context c
+) {
+  if (!(
+    c.recentField == "selectedId"
+  )) {
+    c.recentField = "none";
+    return c;
+  }
+  if (
+    c.selectedItems.size() == 2
+  ) {
+    c.selectedItems.clear();
+  }
+  c.selectedItems.push_back(c.selectedId);
+  c.recentField = "selectedItems";
+  return c;
+}
+
+
diff --git a/v4/memory_test.cpp b/v4/memory_test.cpp
index 1cc2e77..3f6513b 100644
--- a/v4/memory_test.cpp
+++ b/v4/memory_test.cpp
@@ -7,208 +7,232 @@
 #include "memory_Context.h"
 #include "shell.h"
 
-std::string memory_test_generateConstPlayfield(
+
+
+
+std::string memory_test_detectMismatchedItems(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
+  // Select two items of different groups.
+  c.selectedId = 0;
+  c.recentField = "selectedId";
+  c = memory_selectItem(c);
+  c.selectedId = 2;
+  c.recentField = "selectedId";
+  c = memory_selectItem(c);
+  // Detect mismatching.
+  c = memory_detectMismatchedItems(c);
+  // See if the two selected items do not match.
   if (
-    c.recentField == "playfieldItems" &&
-    c.playfieldItems.size() == 4 &&
-    c.playfieldItems[0] == 0 &&
-    c.playfieldItems[1] == 0 &&
-    c.playfieldItems[2] == 1 &&
-    c.playfieldItems[3] == 1
+    c.recentField == "mismatchedItems" &&
+    c.mismatchedItems.size() == 2 &&
+    c.mismatchedItems[0] == 0 &&
+    c.mismatchedItems[1] == 2
   ) {
-    return "OK: memory_generateConstPlayfield";
+    return "OK: memory_detectMismatchedItems";
   }
-  return "ERR: memory_generateConstPlayfield";
+  return "ERR: memory_detectMismatchedItems";
 }
 
 
 
-std::string memory_test_selectItem_1x(
+
+std::string memory_test_detectMismatchedItems_itemTwice(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
-  // Select the first item.
+  // Select the same item twice.
   c.selectedId = 0;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
-  // See if it's in selectedItems now.
+  c.selectedId = 0;
+  c.recentField = "selectedId";
+  c = memory_selectItem(c);
+  // Detect mismatching.
+  c = memory_detectMismatchedItems(c);
+  // See if the two selected items do not match.
   if (
-    c.recentField == "selectedItems" &&
-    c.selectedItems.size() == 1 &&
-    c.selectedItems[0] == 0
+    c.recentField == "mismatchedItems" &&
+    c.mismatchedItems.size() == 1 &&
+    c.mismatchedItems[0] == 0
   ) {
-    return "OK: memory_selectItem_1x";
+    return "OK: memory_detectMismatchedItems_itemTwice";
   }
-  return "ERR: memory_selectItem_1x";
+  return "ERR: memory_detectMismatchedItems_itemTwice";
 }
 
 
 
-std::string memory_test_selectItem_2x(
+
+
+
+
+std::string memory_test_detectVictory(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
-  // Select the first two items.
+  // Select the first two items of the same group.
   c.selectedId = 0;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
   c.selectedId = 1;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
-  // See if both items are selected now.
+  // Hide the first pair.
+  c = memory_hideMatchingItems(c);
+  // Select the last two items of the same group.
+  c.selectedId = 2;
+  c.recentField = "selectedId";
+  c = memory_selectItem(c);
+  c.selectedId = 3;
+  c.recentField = "selectedId";
+  c = memory_selectItem(c);
+  // Hide the second pair.
+  c = memory_hideMatchingItems(c);
+  // Detect victory.
+  c = memory_detectVictory(c);
+  // See if victory has been detected.
   if (
-    c.recentField == "selectedItems" &&
-    c.selectedItems.size() == 2 &&
-    c.selectedItems[0] == 0 &&
-    c.selectedItems[1] == 1
+    c.recentField == "victory" &&
+    c.victory == true
   ) {
-    return "OK: memory_selectItem_2x";
+    return "OK: memory_detectVictory";
   }
-  return "ERR: memory_selectItem_2x";
+  return "ERR: memory_detectVictory";
 }
 
-
-
-std::string memory_test_selectItem_3x(
+std::string memory_test_generateConstPlayfield(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
-  // Select three items.
-  c.selectedId = 0;
-  c = memory_selectItem(c);
-  c.selectedId = 1;
-  c = memory_selectItem(c);
-  c.selectedId = 2;
-  c = memory_selectItem(c);
-  // See if only one (last) item is selected now.
   if (
-    c.recentField == "selectedItems" &&
-    c.selectedItems.size() == 1 &&
-    c.selectedItems[0] == 2
+    c.recentField == "playfieldItems" &&
+    c.playfieldItems.size() == 4 &&
+    c.playfieldItems[0] == 0 &&
+    c.playfieldItems[1] == 0 &&
+    c.playfieldItems[2] == 1 &&
+    c.playfieldItems[3] == 1
   ) {
-    return "OK: memory_selectItem_3x";
+    return "OK: memory_generateConstPlayfield";
   }
-  return "ERR: memory_selectItem_3x";
+  return "ERR: memory_generateConstPlayfield";
 }
 
 
 
 
-std::string memory_test_shouldDeselectMismatchedItems(
+std::string memory_test_hideMatchingItems(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
-  // Select two items of different groups.
+  // Select two items of the same group.
   c.selectedId = 0;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
-  c.selectedId = 2;
+  c.selectedId = 1;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
-  // Detect mismatching.
-  c = memory_shouldDeselectMismatchedItems(c);
-  // See if the two selected items do not match.
+  // Hide matching items.
+  c = memory_hideMatchingItems(c);
+  // See if the two selected items match.
   if (
-    c.recentField == "mismatchedItems" &&
-    c.mismatchedItems.size() == 2 &&
-    c.mismatchedItems[0] == 0 &&
-    c.mismatchedItems[1] == 2
+    c.recentField == "hiddenItems" &&
+    c.hiddenItems.size() == 2 &&
+    c.hiddenItems[0] == 0 &&
+    c.hiddenItems[1] == 1
   ) {
-    return "OK: memory_shouldDeselectMismatchedItems";
+    return "OK: memory_hideMatchingItems";
   }
-  return "ERR: memory_shouldDeselectMismatchedItems";
+  return "ERR: memory_hideMatchingItems";
 }
 
 
 
-
-std::string memory_test_shouldDeselectMismatchedItems_itemTwice(
+std::string memory_test_selectItem_1x(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
-  // Select the same item twice.
-  c.selectedId = 0;
-  c = memory_selectItem(c);
+  // Select the first item.
   c.selectedId = 0;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
-  // Detect mismatching.
-  c = memory_shouldDeselectMismatchedItems(c);
-  // See if the two selected items do not match.
+  // See if it's in selectedItems now.
   if (
-    c.recentField == "mismatchedItems" &&
-    c.mismatchedItems.size() == 1 &&
-    c.mismatchedItems[0] == 0
+    c.recentField == "selectedItems" &&
+    c.selectedItems.size() == 1 &&
+    c.selectedItems[0] == 0
   ) {
-    return "OK: memory_shouldDeselectMismatchedItems_itemTwice";
+    return "OK: memory_selectItem_1x";
   }
-  return "ERR: memory_shouldDeselectMismatchedItems_itemTwice";
+  return "ERR: memory_selectItem_1x";
 }
 
 
 
-
-
-
-
-std::string memory_test_shouldDetectVictory(
+std::string memory_test_selectItem_2x(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
-  // Select the first two items of the same group.
+  // Select the first two items.
   c.selectedId = 0;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
   c.selectedId = 1;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
-  // Hide the first pair.
-  c = memory_shouldHideMatchingItems(c);
-  // Select the last two items of the same group.
-  c.selectedId = 2;
-  c = memory_selectItem(c);
-  c.selectedId = 3;
-  c = memory_selectItem(c);
-  // Hide the second pair.
-  c = memory_shouldHideMatchingItems(c);
-  // Detect victory.
-  c = memory_shouldDetectVictory(c);
-  // See if victory has been detected.
+  // See if both items are selected now.
   if (
-    c.recentField == "victory" &&
-    c.victory == true
+    c.recentField == "selectedItems" &&
+    c.selectedItems.size() == 2 &&
+    c.selectedItems[0] == 0 &&
+    c.selectedItems[1] == 1
   ) {
-    return "OK: memory_shouldDetectVictory";
+    return "OK: memory_selectItem_2x";
   }
-  return "ERR: memory_shouldDetectVictory";
+  return "ERR: memory_selectItem_2x";
 }
 
 
 
-
-std::string memory_test_shouldHideMatchingItems(
+std::string memory_test_selectItem_3x(
 ) {
   auto c = memory_createContext();
   c.playfieldSize = 2;
+  c.recentField = "playfieldSize";
   c = memory_generateConstPlayfield(c);
-  // Select two items of the same group.
+  // Select three items.
   c.selectedId = 0;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
   c.selectedId = 1;
+  c.recentField = "selectedId";
   c = memory_selectItem(c);
-  // Hide matching items.
-  c = memory_shouldHideMatchingItems(c);
-  // See if the two selected items match.
+  c.selectedId = 2;
+  c.recentField = "selectedId";
+  c = memory_selectItem(c);
+  // See if only one (last) item is selected now.
   if (
-    c.recentField == "hiddenItems" &&
-    c.hiddenItems.size() == 2 &&
-    c.hiddenItems[0] == 0 &&
-    c.hiddenItems[1] == 1
+    c.recentField == "selectedItems" &&
+    c.selectedItems.size() == 1 &&
+    c.selectedItems[0] == 2
   ) {
-    return "OK: memory_shouldHideMatchingItems";
+    return "OK: memory_selectItem_3x";
   }
-  return "ERR: memory_shouldHideMatchingItems";
+  return "ERR: memory_selectItem_3x";
 }