Fraction to Recurring Decimal

decimal.py

class Solution(object):
    
    def longDivision(self, digit, denominator):
        return digit*10 / denominator, digit*10 % denominator
    
    def getFracs(self, digit, denominator):
        fracs = []
        rem_location = dict()
        rem = digit
        rem_location[rem] = len(fracs)
                
        while digit > 0:
            digit, rem  = self.longDivision(digit, denominator)
            fracs.append(digit)
            if rem in rem_location:
                par_start = rem_location[rem]
                par_end = len(fracs)
                fracs.insert(par_start, '(')
                fracs.insert(par_end+1, ')')
                break
            rem_location[rem] = len(fracs)
            digit = rem
                   
        return fracs
    
    def fractionToDecimal(self, numerator, denominator):
        """
        :type numerator: int
        :type denominator: int
        :rtype: str
        """
        sign = ""
        if numerator * denominator < 0:
            sign = "-"
        if numerator < 0:
            numerator = -numerator
        if denominator < 0:
            denominator = -denominator
        digit = numerator/denominator
        rem = numerator % denominator
        if rem == 0:
            return "%s%d" % (sign, digit)
        fracs = self.getFracs(rem, denominator)
        fracs_str = ""
        for frac in fracs:
            fracs_str = fracs_str + "%s" % frac
        return "%s%d.%s" % (sign, digit, fracs_str)