Solution (leetcode-in-java 1.19 API)

java.lang.Object
- g1301_1400.s1392_longest_happy_prefix.Solution

```
public class Solution
extends Object
```
1392 - Longest Happy Prefix.
Hard

A string is called a happy prefix if is a non-empty prefix which is also a suffix (excluding itself).

Given a string s, return the longest happy prefix of s. Return an empty string "" if no such prefix exists.

Example 1:

Input: s = “level”

Output: “l”

Explanation: s contains 4 prefix excluding itself (“l”, “le”, “lev”, “leve”), and suffix (“l”, “el”, “vel”, “evel”). The largest prefix which is also suffix is given by “l”.

Example 2:

Input: s = “ababab”

Output: “abab”

Explanation: “abab” is the largest prefix which is also suffix. They can overlap in the original string.

Constraints:
- 1 <= s.length <= 10⁵
- s contains only lowercase English letters.

- Constructor Summary
  
  Constructors
  Constructor Description
  
  Solution()
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  String longestPrefix(String s)
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- Solution
```
public Solution()
```

Method Detail

longestPrefix

public String longestPrefix(String s)