Implement strStr().
Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.
题意:返回在字符串中子字符串出现的第一个位置,没有返回-1
这几个题都好简单啊,
1 class Solution(object): 2 def strStr(self, haystack, needle): 3 """ 4 :type haystack: str 5 :type needle: str 6 :rtype: int 7 """ 8 n=haystack.find(needle) 9 return n
暴力C:
1 int strStr(char* haystack, char* needle) { 2 int i,j; 3 int hl,nl; 4 hl=strlen(haystack); 5 nl=strlen(needle); 6 if(nl==0) 7 return 0; 8 if(hl<nl) 9 return -1; 10 for(i=0;i<hl-nl+1;i++){ 11 for(j=0;j<nl;j++){ 12 if(haystack[i+j]!=needle[j]) 13 break; 14 if(j==nl-1) 15 return i; 16 } 17 } 18 return -1; 19 }
还有一种KMP算法,一直想学,一直拖,这两天学会了放上来