1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
# romanNumerals.py
#
# Copyright (c) 2006, 2019, Paul McGuire
#
import pyparsing as pp
def romanNumeralLiteral(numeralString, value):
return pp.Literal(numeralString).setParseAction(pp.replaceWith(value))
one = romanNumeralLiteral("I", 1)
four = romanNumeralLiteral("IV", 4)
five = romanNumeralLiteral("V", 5)
nine = romanNumeralLiteral("IX", 9)
ten = romanNumeralLiteral("X", 10)
forty = romanNumeralLiteral("XL", 40)
fifty = romanNumeralLiteral("L", 50)
ninety = romanNumeralLiteral("XC", 90)
onehundred = romanNumeralLiteral("C", 100)
fourhundred = romanNumeralLiteral("CD", 400)
fivehundred = romanNumeralLiteral("D", 500)
ninehundred = romanNumeralLiteral("CM", 900)
onethousand = romanNumeralLiteral("M", 1000)
numeral = (
onethousand
| ninehundred
| fivehundred
| fourhundred
| onehundred
| ninety
| fifty
| forty
| ten
| nine
| five
| four
| one
).leaveWhitespace()
romanNumeral = numeral[1, ...].setParseAction(sum)
# unit tests
def makeRomanNumeral(n):
def addDigits(n, limit, c, s):
while n >= limit:
n -= limit
s += c
return n, s
ret = ""
n, ret = addDigits(n, 1000, "M", ret)
n, ret = addDigits(n, 900, "CM", ret)
n, ret = addDigits(n, 500, "D", ret)
n, ret = addDigits(n, 400, "CD", ret)
n, ret = addDigits(n, 100, "C", ret)
n, ret = addDigits(n, 90, "XC", ret)
n, ret = addDigits(n, 50, "L", ret)
n, ret = addDigits(n, 40, "XL", ret)
n, ret = addDigits(n, 10, "X", ret)
n, ret = addDigits(n, 9, "IX", ret)
n, ret = addDigits(n, 5, "V", ret)
n, ret = addDigits(n, 4, "IV", ret)
n, ret = addDigits(n, 1, "I", ret)
return ret
# make a string of all roman numerals from I to MMMMM
tests = " ".join(makeRomanNumeral(i) for i in range(1, 5000 + 1))
# parse each roman numeral, and populate map for validation below
roman_int_map = {}
for expected, (t, s, e) in enumerate(romanNumeral.scanString(tests), start=1):
orig = tests[s:e]
if t[0] != expected:
print("{} {} {}".format("==>", t, orig))
roman_int_map[orig] = t[0]
def verify_value(s, tokens):
expected = roman_int_map[s]
if tokens[0] != expected:
raise Exception(
"incorrect value for {} ({}), expected {}".format(s, tokens[0], expected)
)
romanNumeral.runTests(
"""\
XVI
XXXIX
XIV
XIX
MCMLXXX
MMVI
MMMMM
""",
fullDump=False,
postParse=verify_value,
)
|
