LeetCode : Longest Word in Dictionary through Deleting 字典中的最大串-优快云博客

本文介绍了一种算法，用于从给定的字符串中找到字典中最长的可匹配子串，通过删除部分字符。如果存在多个相同长度的匹配项，则选择字典序最小的一个。文章提供了一个示例代码实现，包括如何比较字符串和判断子串的方法。

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试题：
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:
All the strings in the input will only contain lower-case letters.
The size of the dictionary won’t exceed 1,000.
The length of all the strings in the input won’t exceed 1,000.
代码：
将字典中字符串一个一个来比较。

class Solution {
    public String findLongestWord(String s, List<String> d) {
        String max_str = "";
        for(String str : d){
            int max_len = max_str.length();
            int str_len = str.length();
            if(max_len>str_len || (max_len==str_len)&&(max_str.compareTo(str)<0) ) continue;
            if(isSub(s,str)){
                max_str = str;
            }
        }
        return max_str;
    }
    
    private boolean isSub(String s, String str){
        int index=0;
        for(int i=0; i<s.length()&&index<str.length(); i++){
            if(s.charAt(i)==str.charAt(index)){
                index++;
            }
        }
        return index==str.length();
    }
}