Package g0001_0100.s0028_implement_strstr

Class Solution

java.lang.Object
g0001_0100.s0028_implement_strstr.Solution
public class Solution extends Object
28 - Implement strStr().

Easy

Implement strStr().

Return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.

Clarification:

What should we return when needle is an empty string? This is a great question to ask during an interview.

For the purpose of this problem, we will return 0 when needle is an empty string. This is consistent to C’s strstr() and Java’s indexOf().

Example 1:

Input: haystack = “hello”, needle = “ll”

Output: 2

Example 2:

Input: haystack = “aaaaa”, needle = “bba”

Output: -1

Example 3:

Input: haystack = "", needle = ""

Output: 0

Constraints:

  • 0 <= haystack.length, needle.length <= 5 * 104
  • haystack and needle consist of only lower-case English characters.

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • strStr

      public int strStr(String haystack, String needle)