[LeetCode] 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".

class Solution {
public:
    bool wordBreak(string s, unordered_set<string> &dict) {
        bool *flag = new bool[s.size() + 1];
        fill(flag, flag + s.size() + 1, false);
        flag[0] = true;
        for(int i = 1; i < s.size() + 1; i++)
        {
            for(int j = i-1; j >= 0; j--)
            {
                if(flag[j] && dict.find(s.substr(j, i-j)) != dict.end())
                {   
                    flag[i] = true;
                    break;
                }
            }
        }
        return flag[s.size()];
    }
};