[LeetCode]Word Break

https://leetcode.com/problems/word-break/

Got the solution from here http://blog.csdn.net/linhuanmars/article/details/22358863. Quite clever. Interestingly it kind of use the similar approach from a question that I missed in an interview.

public class Solution {    /**     * DP, keeping a an array of boolean called dp[]. dp[i] indicates whether the substring[0~(i-1)] can be segemented.     * At letter k, for all j<k and dp[j] is true, if any of substring[k~j] exists in dictionary, set dp[j] to true     *      **/    public boolean wordBreak(String s, Set<String> dict) {        if(s == null || s.length() == 0) {            return false;        }        boolean dp[] = new boolean[s.length()+1];        dp[0] = true;        for(int i = 0; i < s.length(); i++) {            StringBuilder sb = new StringBuilder(s.substring(0, i+1));            //substring starts at 0 and ends at i (not i+1)            dp[i+1] = false;            for(int j = 0; j <= i; j++) {                if(dp[j] && dict.contains(sb.toString())) {                    dp[i+1] = true;                    break;                }                sb.deleteCharAt(0);            }        }        return dp[s.length()];    }}