Counting unique characters in a String given by the user

Question

I have to write a program that counts the uniques characters in a String given by the user. For example \"abc\" returns 3 and \"aabbccd\" returns 4. I am not allow to use advan

Answer 1

You can use HashSet collections for counting the unique elements in a string. It allow only unique element.

Code Snippet

public static int uniqueCount(String str) 
{
   HashSet al = new HashSet();
   char[] arr= str.toCharArray();
   for (int i=0; i

Refer this link to get full code: ideone