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leetcode - Implement strStr()

2013-04-19 10:29  张汉生  阅读(151)  评论(0)    收藏  举报

题目描述：点击此处

实现的是m*n的算法，KMP算法是m+n的

 1 class Solution {
 2 public:
 3   char *strStr(char *haystack, char *needle) {
 4     // Start typing your C/C++ solution below
 5     // DO NOT write int main() function
 6     int hayLen = strlen(haystack);
 7     int neeLen = strlen(needle);
 8     for (int i=0; i+neeLen<=hayLen; i++, haystack++){
 9       if (haystack == 0)
10         break;
11       int j = 0;
12       for (j=0; j<neeLen && needle[j] == haystack[j]; j++);
13       if (j==neeLen)
14         return haystack;
15     }
16     return NULL;
17   }
18 };