/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
		public static void main(String[] args) {
		Map<String, Integer> dates = new HashMap<String, Integer>();
		dates.put("2015-07-14", 40);
		dates.put("2015-07-15", 8);
		dates.put("2015-07-16", 0);
		dates.put("2015-07-17", 0);
		dates.put("2015-07-18", 0);
		dates.put("2015-08-01", 1);
		dates.put("2015-08-02", 1);
		dates.put("2015-08-03", 2);
		dates.put("2015-08-04", 1);
		
		Map<String, Integer> result = new HashMap<String, Integer>();
		
		for (Entry<String, Integer> entry  : dates.entrySet()) {
			String key = entry.getKey().split("-")[0] + "/" + entry.getKey().split("-")[1];
			Integer value = entry.getValue();
			Integer oldValue = result.get(key) != null ? result.get(key) : 0;
			result.put(key, oldValue + value);
		}
		
		for (Entry<String, Integer> entry  : result.entrySet()) {
			System.out.println("Month " + entry.getKey() + "- Value = " + entry.getValue());
		}
			
	}
	
}