1754 - Largest Merge Of Two Strings.

Medium

You are given two strings word1 and word2. You want to construct a string merge in the following way: while either word1 or word2 are non-empty, choose one of the following options:

• If word1 is non-empty, append the first character in word1 to merge and delete it from word1.

• If word2 is non-empty, append the first character in word2 to merge and delete it from word2.

Return the lexicographically largest merge you can construct.

A string a is lexicographically larger than a string b (of the same length) if in the first position where a and b differ, a has a character strictly larger than the corresponding character in b. For example, "abcd" is lexicographically larger than "abcc" because the first position they differ is at the fourth character, and d is greater than c.

Example 1:

Input: word1 = "cabaa", word2 = "bcaaa"

Output: "cbcabaaaaa"

Explanation: One way to get the lexicographically largest merge is:

• Take from word1: merge = "c", word1 = "abaa", word2 = "bcaaa"

• Take from word2: merge = "cb", word1 = "abaa", word2 = "caaa"

• Take from word2: merge = "cbc", word1 = "abaa", word2 = "aaa"

• Take from word1: merge = "cbca", word1 = "baa", word2 = "aaa"

• Take from word1: merge = "cbcab", word1 = "aa", word2 = "aaa"

• Append the remaining 5 a's from word1 and word2 at the end of merge.

Example 2:

Input: word1 = "abcabc", word2 = "abdcaba"

Output: "abdcabcabcaba"

Constraints:

• 1 <= word1.length, word2.length <= 3000

• word1 and word2 consist only of lowercase English letters.