Problem Word Break

 1 public boolean wordBreak(String s, Set<String> dict) {
 2        Set<Character> set = new HashSet<Character>();
 3         for (int i = 0; i < s.length(); i++) {
 4             set.add(s.charAt(i));
 5         }
 6         for (char a : set) {
 7             boolean found = false;
 8             for (String word : dict) {
 9                 if (word.indexOf((int)a) >= 0) {
10                     found = true;
11                 }
12             }
13 
14             if (! found) {
15                 return false;
16             }
17         }
18 
19         if (s == null || dict.size() == 0 || dict == null) {
20             return false;
21         }
22         if (s.equals("")) return true;
23 
24         for (String word : dict) {
25             if (word.length() <= s.length()) {
26                 if (s.substring(0, word.length()).equals(word)) {
27                     boolean result = wordBreak(s.substring(word.length()), dict);
28                     if (result) return true;
29                 }
30             }
31         }
32 
33         return false;
34     }