import java.util.*;

public class Zoo {
        
    public static void main (String [] args) {

        // We'll use a "HashSet" to keep track of our kangaroos
        HashSet kangaroos = new HashSet ();

        // Let's read the initial population from the command line
        int initialPopulation = Integer.parseInt (args [0]);

        // Let's read the number of years to run the zoo from the command line
        int duration = Integer.parseInt (args [1]);

        // Let's fill our zoo. What assumption are we making here???
        for (int rooIndex = 0; rooIndex < initialPopulation; rooIndex++) {
            kangaroos.add (new Kangaroo ());
        }

        // Display the initial population
        System.out.println ("Year 0: " + initialPopulation + " kangaroos");

        // Step forward, year by year
        for (int yearIndex = 0; yearIndex <= duration; yearIndex++) {

            // Let's keep track of how many births and deaths there have been this year
            int births = 0;
            int deaths = 0;

            // Here, we'll use an array (instead of the HashSet), for convenience
            Kangaroo [] roos = new Kangaroo [kangaroos.size ()];
            kangaroos.toArray (roos);

            // Iterate through the kangaroos
            for (int rooIndex = 0; rooIndex < roos.length; rooIndex++) {

                Kangaroo kangaroo = roos [rooIndex];
                // The kangaroo has aged one year.
                kangaroo.age ();
                
                // Did the kangaroo survive the year?
                if (kangaroo.survive ()) {

                    // Did the kangaroo breed this year?
                    Kangaroo offspring = kangaroo.breed ();
                    if (offspring != null) {

                        // Did the offfspring survive its first year?
                        if (offspring.survive ()) {

                            // Count the offspring as a birth, and add it to the zoo.
                            births++;
                            kangaroos.add (offspring);
                        }
                    }
                }
                else {
                    
                    // Add to the number of deaths, and remove the dead kangaroo from the zoo.
                    deaths++;
                    kangaroos.remove (kangaroo);
                    
                }
            }
            // Display the births and deaths in the year, and the ending population.
            System.out.println ("Year " + (yearIndex + 1) + ": " + births + " births, " + deaths + " deaths, " + kangaroos.size () + " kangaroos");
        }
    }
    
}