How to merge two “strings” with unique values to new String in java? Using converting to arrays or lists

Question

can someone please help me to solve this? Thank you

String a = 1||2||3
String b = 2||4||5

String c = 1||2||3||4||5|| //Must be uniqe

Answer 1

Using converting to arrays or lists? I do not know what your mean. but I suggest

String a = "1||2||3";
String b = "2||4||5";
String[] arrayA = a.split("||");
String[] arrayB = b.split("||");
List<String> list = Arrays.asList(arrayA);
list.addAll(Arrays.asList(arrayB));            
System.console().printf(list.stream().distinct().collect(Collectors.joining("||")));