# 0745. Prefix and Suffix Search

https://leetcode.com/problems/prefix-and-suffix-search

## Description

Design a special dictionary with some words that searchs the words in it by a prefix and a suffix.

Implement the `WordFilter` class:

* `WordFilter(string[] words)` Initializes the object with the `words` in the dictionary.
* `f(string prefix, string suffix)` Returns _the index of the word in the dictionary,_ which has the prefix `prefix` and the suffix `suffix`. If there is more than one valid index, return **the largest** of them. If there is no such word in the dictionary, return `-1`.

**Example 1:**

```
**Input**
["WordFilter", "f"]
[[["apple"]], ["a", "e"]]
**Output**
[null, 0]
**Explanation**
WordFilter wordFilter = new WordFilter(["apple"]);
wordFilter.f("a", "e"); // return 0, because the word at index 0 has prefix = "a" and suffix = 'e".
```

**Constraints:**

* `1 <= words.length <= 15000`
* `1 <= words[i].length <= 10`
* `1 <= prefix.length, suffix.length <= 10`
* `words[i]`, `prefix` and `suffix` consist of lower-case English letters only.
* At most `15000` calls will be made to the function `f`.

## ac

```java
```
