1 files changed, 97 insertions, 0 deletions
diff --git a/089.py b/089.py
new file mode 100644
index 0000000..f8d36be
--- /dev/null
+++ b/089.py
@@ -0,0 +1,97 @@
+
+def value(x):
+    if x == 'I':
+	return 1
+    elif x == 'V':
+	return 5
+    elif x == 'X':
+	return 10
+    elif x == 'L':
+	return 50
+    elif x == 'C':
+	return 100
+    elif x == 'D':
+	return 500
+    elif x == 'M':
+	return 1000
+    else:
+	print "Decoding error: " + x
+	return None
+
+
+def decode_roman(n):
+    result = 0
+    for i in xrange(len(n)-1):	# search for subtractive pairs
+	cur = value(n[i])
+	nxt = value(n[i+1])
+	if cur < nxt:
+	    result -= cur
+	else:
+	    result += cur
+
+    result += value(n[-1])
+    return result
+
+
+def minimal_roman(n):
+    result = ""
+    while n > 0:
+	if n - 1000 >= 0:
+	    n -= 1000
+	    result += "M"
+	elif n - 900 >= 0:
+	    n -= 900
+	    result += "CM"
+	elif n - 500 >= 0:
+	    n -= 500
+	    result += "D"
+	elif n - 400 >= 0:
+	    n -= 400
+	    result += "CD"
+	elif n - 100 >= 0:
+	    n -= 100
+	    result += "C"
+	elif n - 90 >= 0:
+	    n -= 90
+	    result += "XC"
+	elif n - 50 >= 0:
+	    n -= 50
+	    result += "L"
+	elif n - 40 >= 0:
+	    n -= 40
+	    result += "XL"
+	elif n - 10 >= 0:
+	    n -= 10
+	    result += "X"
+	elif n - 9 >= 0:
+	    n -= 9
+	    result += "IX"
+	elif n - 5 >= 0:
+	    n -= 5
+	    result += "V"
+	elif n - 4 >= 0:
+	    n -= 4
+	    result += "IV"
+	elif n - 1 >= 0:
+	    n -= 1
+	    result += "I"
+    return result
+
+
+numbers = []
+
+f = open('089.txt', 'r')
+for line in f:
+    line = line.rstrip('\r\n')
+    numbers.append(line)
+f.close()
+
+saved = 0
+
+for number in numbers:
+    n = decode_roman(number)
+    m = minimal_roman(n)
+    saved += len(number) - len(m)
+
+print saved
+