codewars #75 Numericals of a String (6kyu)

 #75 Numericals of a String

You are given an input string.

For each symbol in the string if it's the first character occurence, replace it with a '1', else replace it with the amount of times you've already seen it...

But will your code be performant enough?

Examples:

input   =  "Hello, World!"

result  =  "1112111121311"

input   =  "aaaaaaaaaaaa"

result  =  "123456789101112"

Note: there will be no int domain overflow (character occurences will be less than 2 billion).

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;

public class JomoPipi {
    public static String numericals(String s) {
        Map<String, AtomicInteger> map = new HashMap<>();
        StringBuilder result = new StringBuilder();

        for (String element :s.split("")) {
            int temp;
            if(map.containsKey(element)){
                temp=map.get(element).incrementAndGet();
            }else{
               temp = 1;
               map.put(element, new AtomicInteger(1));
            }

            result.append(temp);
        }


        return result.toString();
    }
}