Introduction

In this blog post, we will explore how to solve the LeetCode problem "1832" using AI. LeetCode is a popular platform for preparing for coding interviews, and with the help of AI tools like Chatmagic, we can generate solutions quickly and efficiently - helping you pass the interviews and get the job offer without having to study for months.

Problem Statement

A pangram is a sentence where every letter of the English alphabet appears at least once. Given a string sentence containing only lowercase English letters, return true if sentence is a pangram, or false otherwise. Example 1: Input: sentence = "thequickbrownfoxjumpsoverthelazydog" Output: true Explanation: sentence contains at least one of every letter of the English alphabet. Example 2: Input: sentence = "leetcode" Output: false Constraints: 1 <= sentence.length <= 1000 sentence consists of lowercase English letters.

Explanation

Here's the solution:

• High-Level Approach: Use a set to keep track of the unique characters encountered in the sentence. If the size of the set becomes 26, it means all letters of the English alphabet are present.

• Efficiency: This avoids unnecessary iterations or comparisons once all characters are found.

• Complexity:

  • Runtime: O(n), where n is the length of the sentence.
  • Storage: O(1), because the set can hold at most 26 characters.

Code

    def checkIfPangram(sentence: str) -> bool:
    """
    Checks if a string is a pangram (contains all letters of the English alphabet).

    Args:
        sentence: The input string containing lowercase English letters.

    Returns:
        True if the sentence is a pangram, False otherwise.
    """
    seen = set()
    for char in sentence:
        seen.add(char)
        if len(seen) == 26:
            return True
    return False