166. Fraction to recurring Decimal

Given integers representing the numerator and denominator of a fraction, return the fraction in string format.

If the fractional part was repeating, enclose the repeating part in parentheses.

For example,

• Given numerator = 1, denominator = 2, return "0.5".
• Given numerator = 2, denominator = 1, return "2".
• Given numerator = 2, denominator = 3, return "0. (6) ".

Hint:

1. No scary Math, just apply elementary math knowledge. Still remember how to perform a long division?
2. Try a long division on 4/9, and the repeating part is obvious. Now try 4/333. Do you see a pattern?
3. Be wary of Edge cases! List out as many test cases as can think of and test your code thoroughly.

 Public classSolution { PublicString Fractiontodecimal (intNumerator,intdenominator) {        if(Numerator = = 0) {            return"0"; } StringBuilder Res=NewStringBuilder (); //"+" or "-"Res.append (((Numerator > 0) ^ (Denominator > 0))? "-" : ""); Longnum = Math.Abs (Long) numerator); LongDen = Math.Abs ((Long) denominator); //Integral partRes.append (num/den); Num%=den; if(num = = 0) {            returnres.tostring (); }        //Fractional partRes.append ("."); HashMap<long, integer> map =NewHashmap<long, integer>();        Map.put (num, res.length ());  while(num! = 0) {num*= 10; Res.append (Num/den); Num%=den; if(Map.containskey (num)) {intindex =map.get (num); Res.insert (Index,"("); Res.append (")");  Break; }            Else{map.put (num, res.length ()); }        }        returnres.tostring (); }}

166. Fraction to recurring Decimal