Zeller's Algorithm

months = {"01":11, "02":12, "03":1, "04":2, "05":3, "06":4,
"07":5, "08":6, "09":7, "10":8, "11":9, "12":10}
days = {"1":"Monday", "2":"Tuesday","3":"Wednesday","4":"Thursday","5":"Friday","6":"Saturday","0":"Sunday"}

bMonth = input("Want to know the day of the week you were born?\n Enter a number for the month: MM ")
bDay = input("Enter a number for the day: DD ")
bYear = int(input("Enter the two digit year: (e.g. 70 for 1970) YY "))
bCent = int(input("Enter the two digit century: (e.g. 19 for 1970) CC "))
A = int(months[bMonth])
B = int(bDay)
if A == 11 or A == 12:
    if bYear == 00:
        bYear = 99
        bCent = bCent - 1
    else:
        bYear = bYear - 1
C = bYear
D = bCent

W = int((13*A - 1) / 5)
X = int(C / 4)
Y = int(D / 4)
Z = int(W + X + Y + B + C - 2*D)
R = int((Z%7))

if (R < 0):
    R = (R+7)%6

print ("You were born on a " + days[str(R)])