KMP Algorithm and Pattern Matching

The video tutorial introduces the KMP algorithm, a method for pattern matching in strings. It begins with an overview of the naive algorithm, highlighting its inefficiencies due to repeated character comparisons and backtracking. The KMP algorithm is then presented as a more efficient alternative, avoiding unnecessary comparisons by using a prefix table. The tutorial explains the construction of this table and demonstrates the KMP algorithm's operation, emphasizing its linear time complexity compared to the naive approach.

What is the primary purpose of the KMP algorithm?

• Pattern matching

• Sorting numbers

• Calculating averages

• Encrypting data

Which algorithm is known for its inefficiency due to repeated character comparisons?

• Naive algorithm

• Merge sort

• KMP algorithm

• Dijkstra's algorithm

In the naive algorithm, what happens when a mismatch is found?

• The pattern is shifted by two steps

• The entire string is reversed

• The search is terminated

• The pattern is shifted by one step

What is a prefix in the context of pattern matching?

• A random selection of characters

• A subset of characters starting from the end

• A subset of characters from the middle

• A subset of characters starting from the beginning

How does the KMP algorithm improve over the naive algorithm?

• By encrypting the pattern

• By using a different sorting technique

• By avoiding repeated comparisons

• By using more memory

What is the role of the prefix table in the KMP algorithm?

• To store the sorted order of characters

• To store the entire string

• To store the longest prefix which is also a suffix

• To store the encrypted pattern

What is the time complexity of the KMP algorithm?

• O(log n)

• O(n^3)

• O(n + m)

• O(n^2)