# Calculates the amount of pixels the unit has moved from one tick ago as a signed integer value. Negative is up, positive is down.

from copy import deepcopy

UP = False # Negative.
DOWN = True # Positive.
up = 0
down = 0

def DeltaY (direction, a, b, c):
	a_i = Inverse_X(a) # Inverse a.
	b_i = Inverse_X(b) # Inverse b.
	c_i = Inverse_X(c) # Inverse c.

	a_v = [] # Valid a.
	b_v = [] # Valid b.
	c_v = [] # Valid c.

	a_i_t = deepcopy(a_i) # Temporary inverse a.
	while a_i:
		b_i_t = deepcopy(b_i)
		while b_i_t:
			c_i_t = deepcopy(c_i)
			while c_i_t:
				if b_i[0] - a_i[0] == c_i[0]:
					a_v.append(a_i[0])
					b_v.append(b_i[0])
					c_v.append(c_i[0])
				c_i_t.pop(0)
			b_i_t.pop(0)
		a_i.pop(0)

	if len(a_v) >= 2:
		if (a_v[0] > 0 and b_v[0] < a_v[0]) or (a_v[0] < 0 and b_v[0] > a_v[0]):
			if(direction == UP):
				return abs(a_v[0])
			else:
				return -1 * abs(a_v[0])
		else:
			if(direction == UP):
				return -1 * abs(a_v[0])
			else:
				return abs(a_v[0])
	elif len(a_v) >= 1:
		return a_v[0]
	else:
		raise Exception



def Inverse_X (input):
	if Is_Odd(input):
		a = input / 2

		a = a - up
		return [a]
	else:
		a = input / 2
		b = input / 2

		a = down - a
		b = b - up

		return [a, b]

def Is_Odd (input):
	if input % 2 == 1:
		return True
	else:
		return False

up = 6
down = 19
print DeltaY(DOWN, 24, 19, 5)

7