1import java.util.*;
2
3public class Main {
4    public static String mostCommonWord(String paragraph, String[] banned) {
5        Set<String> bannedSet = new HashSet<>(Arrays.asList(banned));
6        Map<String, Integer> wordFreq = new HashMap<>();
7
8        String[] words = paragraph.replaceAll("[^a-zA-Z ]", " ").toLowerCase().split("\s+");
9
10        String result = "";
11        int maxCount = 0;
12
13        for (String word : words) {
14            if (!bannedSet.contains(word)) {
15                wordFreq.put(word, wordFreq.getOrDefault(word, 0) + 1);
16                if (wordFreq.get(word) > maxCount) {
17                    maxCount = wordFreq.get(word);
18                    result = word;
19                }
20            }
21        }
22        return result;
23    }
24
25    public static void main(String[] args) {
26        String paragraph = "Bob hit a ball, the hit BALL flew far after it was hit.";
27        String[] banned = {"hit"};
28        System.out.println(mostCommonWord(paragraph, banned));
29    }
30}

1using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

class Program {
    public static string MostCommonWord(string paragraph, string[] banned) {
        var bannedSet = new HashSet<string>(banned);
        var wordCounts = new Dictionary<string, int>();
        var words = Regex.Matches(paragraph.ToLower(), "\b\w+\b");

        foreach (Match match in words) {
            var word = match.Value;
            if (!bannedSet.Contains(word)) {
                if (!wordCounts.ContainsKey(word)) {
                    wordCounts[word] = 0;
                }
                wordCounts[word]++;
            }
        }

        return wordCounts.Aggregate((a, b) => a.Value > b.Value ? a : b).Key;
    }

    static void Main() {
        string paragraph = "Bob hit a ball, the hit BALL flew far after it was hit.";
        string[] banned = {"hit"};
        Console.WriteLine(MostCommonWord(paragraph, banned));
    }
}