## CheckIO: Repeating decimals

```def convert(numerator, denominator):
to_str = lambda L: ''.join(map(str, L))
decimals, remains = [], []
integer, remain = numerator // denominator, numerator % denominator
remains.append(remain)
while True:
quotient, remain = remain * 10 // denominator, remain * 10 % denominator
decimals.append(quotient)
if not remain:
# doesn't repeat
if sum(decimals):
return '{}.{}'.format(integer, to_str(decimals))
else:
return '{}.'.format(integer)
if remain in remains:
# repeat found
repeat_start = remains.index(remain)
non_repeat, repeat = decimals[:repeat_start], decimals[repeat_start:]
return '{}.{}'.format(
integer, to_str(non_repeat) + '({})'.format(to_str(repeat))
)
else:
remains.append(remain)

if __name__ == '__main__':
#These "asserts" using only for self-checking and not necessary for auto-testing
assert convert(1, 3) == "0.(3)", "1/3 Classic"
assert convert(5, 3) == "1.(6)", "5/3 The same, but bigger"
assert convert(3, 8) == "0.375", "3/8 without repeating part"
assert convert(7, 11) == "0.(63)", "7/11 prime/prime"
assert convert(29, 12) == "2.41(6)", "29/12 not and repeating part"
assert convert(11, 7) == "1.(571428)", "11/7 six digits"
assert convert(0, 117) == "0.", "Zero"```

https://www.checkio.org/mission/repeating-decimals/