Package g1301_1400.s1392_longest_happy_prefix

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    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:

    • <code>1 <= s.length <= 10<sup>5</sup></code>

    • s contains only lowercase English letters.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final String longestPrefix(String s)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait