MinersTask

import java.util.HashMap;
import java.util.Scanner;

public class MinerTask {
    static HashMap<String, Long> elements = new HashMap<>();
    public static void main(String[] args)
    {

        Scanner scn = new Scanner(System.in);
        String command = scn.nextLine();
        int counter = 1;
        String element=command;

        while (!command.equals("stop")){

            if (counter%2==0){
                Long value = Long.valueOf(command);

                process(element, value );



            }
            else {element=command;}

            command=scn.nextLine();

            counter++;
        }

        for (String key:elements.keySet()
             ) {
            System.out.println(key+" -> "+elements.get(key));
        }
    }
    public static void addToElements(String element, Long value){
        elements.put(element, value);
    }
    public static void changeValue(String element, Long value){
        Long newValue = elements.get(element)+value;
        elements.put(element, newValue);
    }
    public static void process(String element, Long value){
        if (!elements.containsKey(element)){
            addToElements(element, value);
        }
        else changeValue(element, value);
    }
}