LeetCode 28. Implement strStr

Description

Implement strStr().

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

Example

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().

Code

• java

class Solution {
    public int strStr(String haystack, String needle) {
        return haystack.indexOf(needle);
    }
}

Conclusion

• Java的indexOf()环节，自己手写实现的话也不难