Java String Manipulation : Comparing adjacent Characters in Java

Question

i have the following problem
Given a string, return a \"cleaned\" string where adjacent chars that are the same have been reduced to a single char. So \"yyzzza\"

Answer 1

If you aren't restricted to use collections from java.util I recommend to use Set. See example below.

public static String stringClean(String input) {
    Set result = new LinkedHashSet();

    for (char c : input.toCharArray()) {
        result.add(c);
    }

    StringBuilder sb  = new StringBuilder();
    for (char c : result)
        sb.append(c);
    return sb.toString();
}