In [64]:

    

class ZeroDivisionException(Exception):
    pass

class Fraction():    
    def __init__(self, up, down):
        if down == 0:
            raise ZeroDivisionException
        
        self.up = up
        self.down = down
        
    def __add__(self, other):
        result = Fraction(self.up * other.down +self.down*other.up,
                          self.down*other.down).cancel()
        return result
    
    def __sub__(self, other):
        result = Fraction(self.up * other.down -self.down*other.up,
                          self.down*other.down).cancel()
        return result
    
    def __mul__(self, other):
        return Fraction(self.up * other.up, self.down * other.down).cancel()
    
    def __truediv__(self, other):
        return Fraction(self.up * other.down, self.down * other.up).cancel()
    
    def __repr__(self):
        return '{}/{}'.format(self.up, self.down)
    
    def _gcd(self):
        if self.up > self.down:
            b = self.up
        else: 
            b = self.down
            
        for x in range(b, 0, -1):
            if self.up % x == 0 and self.down % x == 0:
                return x
        return 1
    
    def cancel(self):
        gcd = self._gcd()
        up = self.up // gcd
        down = self.down // gcd
        return Fraction(up, down)


    

In [66]:

    

print(Fraction(1,2) / Fraction(1,2))
print(Fraction(1,2) * Fraction(1,2))
print(Fraction(1,2) - Fraction(1,2))
print(Fraction(2,6) + Fraction(3,4))


    

    




1/1
1/4
0/1
13/12

In [60]:

    

Fraction(2,4).cancel()


    

    
Out[60]:





1/2