Description
Implement strStr().
Return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.
Example 1:
1 | Input: haystack = "hello", needle = "ll" |
Example 2:
1 | Input: haystack = "aaaaa", needle = "bba" |
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()).