question2.md

Problem Statement

Write a function group_by_first_letter(words: list) -> dict which takes a list of words as its argument. The function should return a dictionary where:

• The keys of the dictionary are the first letters of ther words.
• The values are lists of words starting with the letter the corresponding key.
• Words in each list should sorted in ascending alphabetical order

Constraints

• The input list will only contain strings.
• Words will be lowercase alphabets only (No special characters or numbers.)
• The list may contain duplicate words.

Solution

def group_by_first_letter(words: list) -> dict:
    grouped = {}
    for word in words:
        f_letter = word[0]
        if f_letter not in grouped:
            grouped[f_letter] = []
        grouped[first_letter].append(word)
    
    #sorting each list of words
    for key in grouped:
        grouped[key].sort()
    
    return grouped

Public Test Cases

Test Case 1:

Input:

['apple', 'banana', 'ant', 'blueberry', 'cherry']

Expected Output:

{'a': ['ant', 'apple'], 'b': ['banana', 'blueberry'], 'c': ['cherry']}

Test Case 2:

Input:

["dog", "cat", "deer", "antelope", "apple", "car"]

Expected Output:

{'d': ['deer', 'dog'], 'c': ['car', 'cat'], 'a': ['antelope', 'apple']}

Private Test Cases

Test Case 1:

Input:

["zoo", "zebra", "apple", "ant", "ant", "zebra",  "antelope"]

Expected Output:

{'z': ['zebra', 'zebra', 'zoo'], 'a': ['ant', 'ant', 'antelope', 'apple']}

Test Case 2:

Input:

["kiwi", "kale", "kangaroo", "apple", "ant", "banana", "caulifla"]

Expected Output:

{'k': ['kale', 'kangaroo', 'kiwi'], 'a': ['ant', 'apple'], 'b': ['banana'], 'c': ['caulifla']}

Test Case 3:

Input:

["carrot", "cucumber", "celery", "date", "dragonfruit", "gogeta", "gojo"]

Expected Output:

{'c': ['carrot', 'celery', 'cucumber'], 'd': ['date', 'dragonfruit'], 'g': ['gogeta', 'gojo']}

Test Case 4:

Input:

["pine", "pear", "pomegranate", "peach", "plum"]

Expected Output:

{'p': ['peach', 'pear', 'pine', 'plum', 'pomegranate']}