Hashset Решение задачи 6

src/com/school/faang/hashset/задача_6/RecommendationEngine.java

@@ -0,0 +1,38 @@
+package com.school.faang.hashset.задача_6;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Set;
+
+public class RecommendationEngine {
+    private HashMap<String, HashSet<String>> videosByChannel;
+
+    public RecommendationEngine(HashMap<String, HashSet<String>> videosByChannel) {
+        this.videosByChannel = videosByChannel;
+    }
+
+    public void addVideo(String channelName, String videoTitle) {
+        if (!videosByChannel.containsKey(channelName)) {
+            HashSet<String> hashSet = new HashSet<>();
+            hashSet.add(videoTitle);
+            videosByChannel.putIfAbsent(channelName, hashSet);
+        } else {
+            videosByChannel.get(channelName).add(videoTitle);
+        }
+    }
+
+    public List<String> generateFeed(HashSet<String> subscriptions, HashSet<String> watchHistory) {
+        Set<String> recommendations = new HashSet<>();
+        videosByChannel
+                .values()
+                .stream()
+                .forEach(setVideo -> recommendations.addAll(setVideo));
+        recommendations.removeAll(watchHistory);
+        List<String> finalField = new ArrayList<>(recommendations);
+        Collections.shuffle(finalField);
+        return finalField;
+    }
+}

src/com/school/faang/hashset/задача_6/Solution.java

@@ -1,7 +1,56 @@
 package com.school.faang.hashset.задача_6;
 
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Set;
+
 public class Solution {
     public static void main(String[] args) {
+        RecommendationEngine recommendationEngine = new RecommendationEngine(new HashMap<>());
+        Set<String> subscriptions = new HashSet<>();
+        subscriptions.add("TechWorld with Nana");
+        subscriptions.add("Daily Dose of Internet");
+        subscriptions.add("Veritasium");
+        subscriptions.add("Kurzgesagt – In a Nutshell");
+        subscriptions.add("MKBHD");
+        subscriptions.add("CrashCourse");
+        subscriptions.add("Tom Scott");
+        subscriptions.add("MrBeast");
+        subscriptions.add("Yuri Dud");
+        subscriptions.add("Real Engineering");
+
+        Set<String> watchHistory = new HashSet<>();
+        watchHistory.add("Why Planes Don't Fly Over Tibet");
+        watchHistory.add("Building a PC in 10 Minutes");
+        watchHistory.add("10 Amazing Science Experiments");
+        watchHistory.add("The Truth About the Internet");
+        watchHistory.add("How Engines Work");
+        watchHistory.add("I Survived 50 Hours in a Jungle");
+        watchHistory.add("Why We Age – And How We Can Stop It");
+        watchHistory.add("Top 10 Programming Languages in 2025");
+        watchHistory.add("Inside the Mind of a Master Procrastinator");
+        watchHistory.add("This Is Why You Don’t Skip Leg Day");
+
+        recommendationEngine.addVideo("TechWorld with Nana", "Kubernetes Explained in 10 Minutes");
+        recommendationEngine.addVideo("Kurzgesagt – In a Nutshell", "Why We Age – And How We Can Stop It"); // из watchHistory
+        recommendationEngine.addVideo("Veritasium", "The Science of Laziness");
+        recommendationEngine.addVideo("MrBeast", "Last To Leave Circle Wins $500,000");
+        recommendationEngine.addVideo("Kurzgesagt – In a Nutshell", "What If The Earth Stopped Spinning?");
+        recommendationEngine.addVideo("CrashCourse", "Top 10 Programming Languages in 2025"); // из watchHistory
+        recommendationEngine.addVideo("Veritasium", "Inside the Mind of a Master Procrastinator"); // из watchHistory
+        recommendationEngine.addVideo("MKBHD", "iPhone 15 Review: Too Good to Ignore!");
+        recommendationEngine.addVideo("MrBeast", "I Spent 7 Days Buried Alive");
+        recommendationEngine.addVideo("Real Engineering", "Why Planes Don't Fly Over Tibet"); // из watchHistory
+        recommendationEngine.addVideo("Veritasium", "This Puzzle Seems Impossible... Until You Know the Trick");
+        recommendationEngine.addVideo("CrashCourse", "Introduction to Artificial Intelligence");
+        recommendationEngine.addVideo("Tom Scott", "The Tunnel That Was Buried Twice");
+        recommendationEngine.addVideo("Real Engineering", "Why Modern Planes Don’t Have Supersonic Speed");
 
+        recommendationEngine
+                .generateFeed(
+                        (HashSet<String>) subscriptions,
+                        (HashSet<String>)watchHistory)
+                .stream()
+                .forEach(System.out::println);
     }
 }