Subdomain Visit Count

给一个string, 里面的数字代表访问的数量,字符代表domain, 求统计sub domain的访问次数.

class Solution {
    public List<String> subdomainVisits(String[] cpdomains) {
            List<String> res = new ArrayList<>();
            Map<String, Integer> map = new HashMap<>();
            for(String s : cpdomains) {
                String[] strs = s.split(" ");
                int c = Integer.valueOf(strs[0]);
                StringBuilder sb = new StringBuilder(strs[1]);
                while (sb.indexOf(".") != -1) {
                    map.put(sb.toString(), map.getOrDefault(sb.toString(), 0) + c);
                    sb.delete(0, sb.indexOf(".")+1);
                }
                map.put(sb.toString(), map.getOrDefault(sb.toString(), 0) + c);
            }
            for(Map.Entry<String, Integer> e : map.entrySet()){
                res.add(e.getValue() + " " + e.getKey());
            }
            return res;
        }
}