public boolean wordBreak(String s, List<String> wordDict) {

HashSet<String> words=new HashSet(wordDict);

int n=s.length();

boolean[] dp=new boolean[n+1];

int len=0;

for(String word: wordDict) len=Math.max(len,word.length());

dp[0]=true;

for(int i=0;i<n;i++){

if(!dp[i]) continue;

for(int l=1;i+l<=n && l <= len ; l++){

if(words.contains(s.substring(i,i+l))) dp[i+1]=true;

}

}

return dp[n];

}