LeetCode——Word Break

Word Break

Given a string s and a dictionary of words dict, determine if s can be segmented into a space-separated sequence of one or more dictionary words.

For example, given
s = "leetcode",
dict = ["leet", "code"].

Return true because "leetcode" can be segmented as "leet code".

Java代码：

public class Solution {
    public boolean wordBreak(String s, Set<String> dict) {
        List<Integer> list = new ArrayList<Integer>();  
        for (int i = s.length() - 1; i >= 0; i--) {  
            String sub = s.substring(i);  
            if (dict.contains(sub)) {  
                list.add(i);  
            } else {  
                for (Integer index : list) {  
                    sub = s.substring(i, index);  
                    if (dict.contains(sub)) {  
                        list.add(i);  
                        break;  
                    }  
                }  
            }  
        }  
        if (list.isEmpty()) {  
            return false;  
        } else {  
            Integer index = list.get(list.size() - 1);  
            return index == 0;  
        }  
    }
}

自己弄了半天没有弄出来

上述代码参考网络，动态规划的实现还是没有弄明白。