leetcode 139. Word Break

Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, determine if s can be segmented into a space-separated sequence of one or more dictionary words. You may assume the dictionary does not contain duplicate words.For example, givens = "leetcode",dict = ["leet", "code"].Return true because "leetcode" can be segmented as "leet code".UPDATE (2017/1/4):The wordDict parameter had been changed to a list of strings (instead of a set of strings). Please reload the code definition to get the latest changes.

采用动态规划，dp[i]表示目标字符串s中0-i是否合法

public class Solution {    public boolean wordBreak(String s, List<String> wordDict) {        boolean[] res = new boolean[s.length() +1];        res[0] = true;        for(int i=1; i < s.length()+1; i++){            for(String str : wordDict){                if(str.length() <=i){                    if(res[i-str.length()]){                        if(s.substring(i-str.length(), i).equals(str)){                            res[i] = true;                            break;                        }                    }                }            }        }        return res[s.length()];    }}