SDET-2

You are given two strings ‘A’ and ‘B’ of length ‘N’ and ‘M’ respectively. You need to construct a new string ‘C’ by merging both strings in such a way that the relative order of characters in ‘A’ and ‘B’ is the same in string ‘C’.

For example, if the string ‘A’ is of length 3 then the first character of string ‘A’ should be placed before the second and third characters of string ‘A’ in string ‘C’. Similarly, the second character of string ‘A’ should be placed after the first character and before the third character of string ‘A’ in string ‘C’.

The cost of merging the strings is given by the number of consecutive characters in string ‘C’ that are not equal + 1, i.e. ‘C[ i ] != ‘C[ i + 1]’.

Find the minimum cost of merging both strings.

Example:

Input: ‘N’ = 3, ‘M’ = 3, ‘A’ = aba, ‘B’ = aab 

Output: 3

One of the valid strings with minimum cost after merging ‘A’ and ‘B’ is ‘aaabba’. The order of characters of string ‘A’ as well as ‘B’ is maintained in the string ‘aaabba’ and the cost of this string is (1 + 2) = 3.

Ninja is now bored with numbers and is now playing with characters but hates when he gets repeated characters. Ninja is provided a string, and he wants to return the first unique character in the string.The string will contain characters only from the English alphabet set, i.e., ('A' - 'Z') and ('a' - 'z'). If there is no non-repeating character, print the first character of the string. If there is no non-repeating character, return the first character of the string.

Design a forum-like systems like Quora, Reddit or HackerNews.