LeetCode OJ——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=false; 
		if(1>s.length())
			return true;
		if(1==s.length())
			return(dict.count(s));
		for(int n=0;n<s.length()-1;n++)
		{
			
			if(dict.count(s.substr(0,n)))
			    if(dict.count(s.substr(n+1)))
			        return true;
			    else
			        flag=wordBreak(s.substr(n+1),dict);
		}
    }
};

注：超时