524. Longest Word in Dictionary

Given a string and a string dictionary, find the longest string in the dictionary that can be formed by deleting some characters of the given string. If there are more than one possible results, return the longest word with the smallest lexicographical order. If there is no possible result, return the empty string.
Example 1:

Input:
s = "abpcplea", d = ["ale","apple","monkey","plea"]

Output: 
"apple"

Example 2:

Input:
s = "abpcplea", d = ["a","b","c"]

Output: 
"a"

Note:

1. All the strings in the input will only contain lower-case letters.
2. The size of the dictionary won't exceed 1,000.
3. The length of all the strings in the input won't exceed 1,000.

一刷
有个很简单的方法：

1. 首先把字典sort, length长的在前，length相同，则根据lexicographical order
2. 然后最朴素的字符串匹配，对于字典中的每个单词word，从index为0开始。如果和s中的字符匹配上了，i++。最后判断i==word.length()

class Solution {
    public String findLongestWord(String s, List<String> d) {
        Collections.sort(d, (a, b)->a.length()!=b.length()?b.length()-a.length():a.compareTo(b));
        char[] arr = s.toCharArray();
        for(String word:d){
            int i=0;
            for(char ch:arr){
                if(ch == word.charAt(i)) i++;
                if(i == word.length()) return word;
            }
        }
        return "";
    }
}