lc28. Implement strStr().py

class Solution:
    def strStr(self, haystack, needle):
        """
        :type haystack: str
        :type needle: str
        :rtype: int
        """
        for i in range(len(haystack) - len(needle) + 1):
            if haystack[i:i + len(needle)] == needle:
                return i
        return -1


haystack = "hello"
needle = ""

s = Solution()

print(s.strStr(haystack, needle))