Merge Strings Alternately

Problem Description

You are given two strings word1 and word2. Merge the strings by adding letters in alternating order, starting with word1. If a string is longer than the other, append the additional letters onto the end of the merged string. Return the merged string.

Key Insights

• The merging process alternates between characters from word1 and word2.
• If one string is longer, its remaining characters should be appended to the end of the merged string.
• A two-pointer technique can efficiently traverse the strings and build the result.

Space and Time Complexity

Time Complexity: O(n + m), where n and m are the lengths of word1 and word2, respectively.
Space Complexity: O(1), since we are using a fixed amount of extra space for the result string.

Solution

To solve the problem, we can employ a two-pointer approach. We initialize pointers for both strings and iterate through them, appending characters from each string alternately to a result list. If we reach the end of one string, we append the remaining characters of the other string. Finally, we join the result list into a single string.

Code Solutions