Learn how to solve the Leetcode problem of id 242, whose title is Valid Anagram, using the Java programming language.

https://leetcode.com/problems/valid-anagram

The Data Structures and Algorithms (DSA) lesson uses an array of counts to keep track of the discrepancy in the frequency of the characters.

Right off the bat, if the length of the two strings is not the same, they are not a valid anagram.

If the strings have the same length, we have to check if the frequency of the characters in each string matches.

When a character is seen on the first string s, the count for that specific character is incremented.

When a character is seen on the second string t, the count for the specific character is decremented.

That way, when a character is both seen in the first string and the second string, the count for that should be zero because they will cancel out.

So, the problem in the end is about going through the array of counts to see if any of them is not zero, meaning there is a discrepancy.

If all the counts end up being 0 that means it is a valid anagram since each repeated character canceled out in one string to another.

The time complexity for the solution is O(n) and its space complexity is O(1).

DSA problems are sometimes asked during tech job interviews for positions such as Software Engineer, so you can use the challenge to practice that skill.