LeetCode28. Implement strStr()

LeetCode28. Implement strStr()

题目：

Implement strStr().

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

Example 1:

Input: haystack = "hello", needle = "ll"
Output: 2

Example 2:

Input: haystack = "aaaaa", needle = "bba"
Output: -1

题目分析：直接用string的find函数

代码：

class Solution {  
public:  
    int strStr(string haystack, string needle) {  
        int tmp = haystack.find(needle);  
        if (tmp == string::npos)
            return -1;
        return tmp;
    }  
};