在重复字符之间拆分字符串

Question

I want to take any given string and split it based on repeating characters.

As an example, if I were to input the string abcaaabbc , I would want to output an array of strings equal to: [abca, a, ab, bc] . Each time a character repeats, I want to start a new string.

Doing this with a loop is possible, of course, but I am wondering if I can achieve it using the String.split() method. If so - what would the RegEx be?

Answer 1

Tokenize the input string where previous character(look-behind (?<=(.)) ) is same as next character(look-ahead (?=\\\\1) ) and \\1 captures (.) .

    String str = "abcbabaaabbc";
    String regex = "(?<=(.))(?=\\1)";        
    System.out.println(Arrays.toString(str.split(regex)));

Answer 2

From a performance perspective, I would stick with a loop. It runs in O(n) time. The string.split(regex) has been known to be slow. I recently used it in place of a loop and found that it was O(n^2) compared to the O(n) loop.

KISS principal works here