Leetcode 28. Implement strStr () string

Implement StrStr ()

Implement strStr ().

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

find the position that matches the first needle in the haystack. If not found, returns-1.

The code is as follows:

Class solution {public:    int strstr (string haystack, string  needle)  {        if (haystack.size ()  == 0  && needle.size ()  == 0)              return 0;        if (Needle.size ()  == 0)             return 0;         if (Haystack.size ()  < needle.size ())              return -1;        for (int  i = 0;i < haystack.size ()  - needle.size ()  + 1;i++)          {             bool flag = true;            if (Needle[0] == haystack[i])             {                 int j = 0;                 for (; j <  Needle.size (); j + +)                  {                     if (Needle[j] != haystack[i+j])                      {                          Flag = false;                         break;                     }                                          }       &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;IF (flag)                      return i;             }        }         return -1;    }};

2016-08-11 01:02:49

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Leetcode 28. Implement strStr () string