Problem Description
You have a chat log of n messages. You are given two string arrays messages and senders where messages[i] is a message sent by senders[i]. A message is a list of words that are separated by a single space with no leading or trailing spaces. The word count of a sender is the total number of words sent by the sender. Return the sender with the largest word count. If there is more than one sender with the largest word count, return the one with the lexicographically largest name.
Key Insights
- Count the number of words in each message to determine the total word count for each sender.
- Use a hash table (dictionary) to store the cumulative word counts for each sender.
- Compare the word counts and handle ties by checking for lexicographical order.
Space and Time Complexity
Time Complexity: O(n * m), where n is the number of messages and m is the average number of words in the messages. Space Complexity: O(k), where k is the number of unique senders.
Solution
To solve this problem, we can use a hash table (dictionary) to keep track of the total word counts for each sender. We will iterate through the messages and their corresponding senders, splitting each message into words to count them. After calculating the total word counts for each sender, we will determine which sender has the highest count. In case of a tie, we will return the sender with the lexicographically larger name.