![Verifying An Alien Dictionary Leetcode Problem 953 [Python Solution]](https://auditorical.com/wp-content/uploads/2023/10/Verifying-An-Alien-Dictionary-Leetcode-Problem-953-Python-Solution-1.webp)
Verifying An Alien Dictionary Leetcode Problem 953 [Python Solution]
In this blog post, we’ll dive into solving a fascinating problem from LeetCode, Verifying An Alien Dictionary This problem is not only a great exercise in coding but also a fun way to explore the concept of an alien language.
We’ll provide a Python solution for this problem and explain the logic behind it.
If you’re new to coding or just want to understand this specific problem better, you’re in the right place.
Problem Overview
The problem statement is as follows: In an alien language, the alphabet consists of lowercase English letters, but in a different order.
Your task is to determine if a given list of words is sorted lexicographically in this alien language.
In other words, you need to check if the words are arranged correctly according to the given alien alphabet order.
Example 1:
Let’s take a look at an example to better understand the problem:
Input: words = ["hello", "leetcode"], order = "hlabcdefgijkmnopqrstuvwxyz"
Output: true
Explanation: In this alien language, ‘h’ comes before ‘l’, which is why the sequence is sorted.
We’ll see how to achieve this verification shortly.
Understanding Alien Language Constraints
Before we dive into the code, let’s understand the constraints:
- The input consists of an array of words, with a maximum length of 100 words.
- Each word in the array has a maximum length of 20 characters.
- The order of the alien alphabet is provided and has a fixed length of 26 characters (representing the English lowercase alphabet).
- All characters in both the words and the order are English lowercase letters.
Verifying An Alien Dictionary LeetCode Problem Solution
Now, let’s explore a Python solution to this problem.
Bruteforce Approach
Here is the Python code for a straightforward approach to solving this problem:
def isAlienSorted(words, order):
# Create a dictionary to map characters to their positions in the order
orderInd = {c: i for i, c in enumerate(order)}
for i in range(len(words) - 1):
w1, w2 = words[i], words[i + 1]
for j in range(len(w1)):
if j == len(w2):
return False
if w1[j] != w2[j]:
if orderInd[w2[j]] < orderInd[w1[j]]:
return False
break
return True
This code first creates a dictionary, orderInd, to map characters to their positions in the given alien language order.
It then compares each pair of adjacent words to ensure they are in the correct order based on the alien language.
If at any point, the code finds a pair of characters that are out of order, it returns False.
If it goes through all the word pairs without finding any issues, it returns True.
Time and Space Complexity
The time complexity of this solution is O(N * M), where N is the number of words, and M is the average length of words in the input.
The space complexity is O(1) because the dictionary orderInd has a fixed size of 26 characters.
Reasoning Behind Our Approach
The key to solving this problem lies in understanding that we need to compare characters in each word based on their positions in the given alien alphabet order.
By comparing characters one by one and ensuring that they are in the correct order, we can determine whether the words are sorted in the alien language.
Related Interview Questions By Company:
- Same Tree LeetCode
- Concatenation Of Array LeetCode
- Find All Numbers Disappeared In An Array LeetCode
Related Interview Questions By Difficulty:
- Number Of Connected Components In An Undirected Graph LeetCode
- Pacific Atlantic Water Flow LeetCode
- Course Schedule II LeetCode
Related Interview Questions By Category:
Conclusion
In this blog post, we explored the LeetCode problem Verifying An Alien Dictionary and provided a Python solution that checks if a given list of words is sorted in a specific alien language order.
We discussed the problem’s constraints, presented a code solution, and explained the reasoning behind our approach.
If you’re new to coding or want to practice your skills, this problem is an excellent way to learn about dictionaries, character comparisons, and algorithm design.
Feel free to ask questions, make suggestions, or share your thoughts in the comments below.
Happy coding!
