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103 lines
1.8 KiB
Python
Executable file
103 lines
1.8 KiB
Python
Executable file
# Rational numbers
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from types import *
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def rat(num, den):
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if type(num) == FloatType or type(den) == FloatType:
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return num/den
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return Rat(num, den)
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def gcd(a, b):
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while b:
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a, b = b, a%b
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return a
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class Rat:
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def __init__(self, num, den):
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if den == 0:
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raise ZeroDivisionError, 'rat(x, 0)'
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if type(den) == FloatType or type(num) == FloatType:
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g = float(den)
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else:
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g = gcd(num, den)
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self.num = num/g
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self.den = den/g
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def __repr__(self):
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return 'Rat(%s, %s)' % (self.num, self.den)
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def __str__(self):
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if self.den == 1:
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return str(self.num)
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else:
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return '%s/%s' % (self.num, self.den)
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def __cmp__(a, b):
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c = a-b
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if c.num < 0:
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return -1
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if c.num > 0:
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return 1
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return 0
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def __float__(self):
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return float(self.num) / float(self.den)
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def __long__(self):
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return long(self.num) / long(self.den)
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def __int__(self):
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return int(self.num / self.den)
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def __coerce__(a, b):
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t = type(b)
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if t == IntType:
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return a, Rat(b, 1)
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if t == LongType:
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return a, Rat(b, 1L)
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if t == FloatType:
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return a, Rat(b, 1.0)
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if t == InstanceType and a.__class__ == b.__class__:
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return a, b
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raise TypeError, 'Rat.__coerce__: bad other arg'
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def __add__(a, b):
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return rat(a.num*b.den + b.num*a.den, a.den*b.den)
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def __sub__(a, b):
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return rat(a.num*b.den - b.num*a.den, a.den*b.den)
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def __mul__(a, b):
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return rat(a.num*b.num, a.den*b.den)
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def __div__(a, b):
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return rat(a.num*b.den, a.den*b.num)
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def __neg__(self):
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return rat(-self.num, self.den)
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def test():
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print Rat(-1L, 1)
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print Rat(1, -1)
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a = Rat(1, 10)
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print int(a), long(a), float(a)
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b = Rat(2, 5)
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l = [a+b, a-b, a*b, a/b]
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print l
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l.sort()
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print l
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print Rat(0, 1)
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print a+1
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print a+1L
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print a+1.0
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try:
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print Rat(1, 0)
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raise SystemError, 'should have been ZeroDivisionError'
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except ZeroDivisionError:
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print 'OK'
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test()
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