题目分析
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, given
s = "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.
代码
class Solution {
public boolean wordBreak(String s, List<String> wordDict) {
boolean[] dp = new boolean[s.length() + 1];
Arrays.fill(dp, false);
dp[s.length()] = true;
for(int i = s.length() - 1; i >= 0; i--) {
for(int j = i; j < s.length(); j++) {
String subStr = s.substring(i, j + 1);
// 当前子字符串在字典中,并且当前字符串后面的字符串也在字典中
// 再加上从后向前遍历,就可以依次保证
if(wordDict.contains(subStr) && dp[j+1] == true) {
dp[i] = true;
break;
}
}
}
return dp[0];
}
}
网友评论