#2284
Sender With Largest Word Count
MediumArrayHash TableStringCountingHash MapArray
Approaches
Brute ForceOptimal
Complexity Comparison
| Brute Force | Optimal Solution★ | |
|---|---|---|
| Time | O(n²) | O(n) |
| Space | O(1) | O(n) |
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Intuition
Time O(n)Space O(n)
The optimal solution uses a single pass through the messages and senders to count the words for each sender using a hash map. This approach is efficient because it minimizes the number of iterations and leverages direct access to counts.
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Algorithm
5 steps- 1Step 1: Initialize a hash map to store the total word counts for each sender.
- 2Step 2: Iterate through the messages and senders simultaneously.
- 3Step 3: For each message, calculate the word count and update the corresponding sender's count in the hash map.
- 4Step 4: After processing all messages, iterate through the hash map to find the sender with the maximum word count.
- 5Step 5: Handle ties by comparing sender names lexicographically.
solution.py14 lines
1# Full working Python code
2messages = ["Hello userTwooo", "Hi userThree", "Wonderful day Alice", "Nice day userThree"]
3senders = ["Alice", "userTwo", "userThree", "Alice"]
4
5def largest_sender(messages, senders):
6 word_count = {}
7 for i in range(len(messages)):
8 count = len(messages[i].split())
9 sender = senders[i]
10 word_count[sender] = word_count.get(sender, 0) + count
11 max_sender = max(word_count.keys(), key=lambda x: (word_count[x], x))
12 return max_sender
13
14print(largest_sender(messages, senders))ℹ
Complexity note: The time complexity is O(n) because we only make a single pass through the messages and senders. The space complexity is O(n) due to the hash map storing the word counts for each sender.
- 1Using a hash map allows for efficient counting and retrieval of word counts.
- 2Lexicographical comparison is crucial when handling ties.
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