class Solution {    public String fractionToDecimal(int numerator, int denominator) {        StringBuilder sb=new StringBuilder();        if(numerator<0&&denominator>0||numerator>0&&denominator<0)            sb.append("-");        long n=Math.abs((long)numerator);        long d=Math.abs((long)denominator);        sb.append(Long.toString(n/d));        long r=n%d;        if(r>0)            sb.append(".");        Map
     
       map=new HashMap
      
       ();        while(r>0&&!map.containsKey(r))        {            map.put(r, sb.length());            sb.append((r*10)/d);            r=(r*10)%d;        }        if(r==0)            return sb.toString();        sb.insert(map.get(r),"(");        sb.append(")");        return sb.toString();    }}