# 524. Longest Word in Dictionary through Deleting

### Description

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.

### Constraints

* 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.

### Approach

### Links

* GeeksforGeeks
* [Leetcode](https://leetcode.com/problems/longest-word-in-dictionary-through-deleting/)
* ProgramCreek
* YouTube

### **Examples**

{% tabs %}
{% tab title="Example 1" %}
**Input:** s = "abpcplea", d = \["ale","apple","monkey","plea"]

**Output:** "apple"
{% endtab %}

{% tab title="Example 2" %}
**Input:** s = "abpcplea", d = \["a","b","c"]

**Output:** "a"
{% endtab %}
{% endtabs %}

### **Solutions**

{% tabs %}
{% tab title="Solution 1" %}

```java
/**
 * Time complexity : O(n*x). One iteration over all strings is required. 
 *    Here n refers to the number of strings in list d and x refers to 
 *    average string length.
 * Space complexity : O(x). result variable is used.
 */

class Solution {
    public String findLongestWord(String s, List<String> d) {
        String result = "";
        if(s == null || d == null) {
            return result;
        }
        for(String str: d) {
            if(isSubsequence(s, str)) {
                if(str.length() > result.length() || 
                   str.length() == result.length() && str.compareTo(result) < 0) {
                    result = str;
                }
            }
        }
        return result;
    }
    
    private boolean isSubsequence(String s1, String s2) {
        if(s2.length() > s1.length()) {
            return false;
        }
        int i = 0;
        for(int j = 0; j < s1.length() && i < s2.length(); j++) {
            if(s1.charAt(j) == s2.charAt(i)) {
                i++;
            }
        }
        return i == s2.length();
    }
}
```

{% endtab %}
{% endtabs %}

### **Follow up**

*


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://code-snippets.hbamithkumara.com/leetcode/problems/501-600/longest-word-in-dictionary-through-deleting.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.