import java.lang.*;

public class Kangaroo {
    
    static final int MALE = 0;
    static final int FEMALE = 1;
    static final double [] FERTILITY = {0, 0.25, 0.5, 0.65, 0.75, 0.9, 0.95, 0.95, 0.95, 0.9, 0.6, 0.4, 0.2, 0};
    static final double [] MORTALITY = {0.45, 0.4, 0.3, 0.3, 0.25, 0.25, 0.25, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0};
    
    private int _age = 0;
    final int gender = (Math.random () < 0.5) ? MALE : FEMALE;
    
    public Kangaroo () {
    }
    
    public int getAge () {
        return this._age;
    }
    
    public void age () {
        this._age++;
    }
    
    public Kangaroo breed () {
        if ((this._age < FERTILITY.length) && (Math.random () < FERTILITY [this._age])) {
            return new Kangaroo ();
        }
        return null;
    }
    
    public boolean survive () {
        if ((this._age < MORTALITY.length) && (Math.random () >= MORTALITY [this._age])) {
            return true;
        }
        return false;
    }
}
