6.15

def chicken_rabbit(num_heads, num_legs):
    chicken = int((2 * num_heads) - (num_legs / 2))
    rabbit = int(num_heads - chicken)
    ans_chicken = ""
    ans_rabbit = ""
    #print(chicken)
    #print(rabbit)
    if(num_legs%2 != 0):
        return ["Invalid inputs received. Program aborted."]
    if(chicken < 0 or rabbit < 0):
        return ["Invalid inputs received. Program aborted."]
    if(chicken == 0):
        ans_chicken = "There isn't any chicken in the cage"
    elif(chicken == 1):
        ans_chicken = "There is 1 chicken in the cage"
    elif(chicken > 1):
        ans_chicken = "There are {0} chickens in the cage".format(chicken)

    if(rabbit == 0):
        ans_rabbit = "There isn't any rabbit in the cage"
    elif(rabbit == 1):
        ans_rabbit = "There is 1 rabbit in the cage"
    elif(rabbit > 1):
        ans_rabbit = "There are {0} rabbits in the cage".format(rabbit)

    return [ans_chicken, ans_rabbit]


def unittest_function_pass():
    # write assertion statements here to test the function
    # enumerate as many test cases you can think of to test your function
    # See "Additional Requirements described in the assignment" for details.
    assert chicken_rabbit(31 , 94) == ["There are 15 chickens in the cage", "There are 16 rabbits in the cage"]


def unittest_function_xfail():
    # write assertion statements here to test the function on any expected failing cases
    # See "Additional Requirements described in the assignment" for details.
    assert chicken_rabbit(2, 6) == ["Invalid inputs received. Program aborted."]

if __name__ == "__main__":

    num_heads = int(input("Input number of heads:\n"))
    num_legs = int(input("Input number of legs:\n"))
    answer = chicken_rabbit(num_heads, num_legs)
    # TODO: add print statements below.
    if len(answer) == 1:
        print(answer[0])
    else:
        print(answer[0])
        print(answer[1])

    # TODO: complete the unittest_function so your function undergo a rigorous unittest created by yourself
    #unittest_function_pass()   #if the num legs are more than the num heads

    # TODO: complete the unittest_function_xfail so your function undergo a rigorous unittest created by yourself
    #unittest_function_xfail()  #more head than legs

    # Please note that unittest_function_xfail is ALWAYS expected to trip an error! Because it is testing on expected failing cases