Solution Explanation for Camelcase Matching

This problem asks to determine if a given query string can be generated from a pattern string by inserting lowercase letters. The core idea is to efficiently compare the query strings with the pattern string, checking for matches while allowing for insertions of lowercase characters. The most efficient approach is using a two-pointer technique.

Approach: Two Pointers

The solution uses a helper function check(s, t) where s is the query string and t is the pattern string. Two pointers, i and j, iterate through s and t respectively.

1. Iteration: The outer loop iterates through the pattern string (t). The inner loop skips lowercase characters in the query string (s) that don't match the current character in the pattern.

2. Mismatch Handling: If a mismatch occurs (the character at s[i] doesn't equal t[j], and s[i] isn't a lowercase character that can be skipped), the function immediately returns false indicating no match.

3. Lowercase Skipping: If s[i] is a lowercase character and doesn't match t[j], the inner loop advances i to skip over these characters.

4. Match Advancement: When a match is found (s[i] == t[j]), both pointers i and j are incremented to proceed to the next characters.

5. End of Pattern: If the end of the pattern is reached (j == n), the remaining characters in s must be lowercase to constitute a valid match. The code checks this condition, returning true if all remaining characters in s are lowercase, and false otherwise.

6. Main Function: The main function iterates through each query string in the queries array and applies the check function to determine the match with the given pattern. The results are stored in a boolean array and returned.

Time and Space Complexity

• Time Complexity: O(m*n), where m is the total length of all query strings and n is the length of the pattern string. This is because the check function has a time complexity of O(len(s)), and it's called for each query string.

• Space Complexity: O(1), as the algorithm uses a constant amount of extra space regardless of the input size.

Code Examples (Python, Java, C++, Go, TypeScript)

The code examples in the problem description demonstrate this two-pointer approach in different programming languages. Each example directly implements the check function as described above and utilizes it within a main loop to process the input queries. The comments within the code clarify each step of the process. The core logic remains consistent across all the provided languages.