Leetcode#28Implement strStr()

Implement strStr().

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

分析，找字符串haystack中最先出现字符串needle的位置，需要注意的是字符串可能为""的情况的处理

public class Solution {

public int strStr(String haystack, String needle) {

if(needle.equals(""))

return 0;

int hl=haystack.length();

int nl=needle.length();

//if(hl==nl)

int j=0;

int i=0;

for(i=0;i<hl-nl+1;i++)

{

for(j=0;j<nl;j++)

if(haystack.charAt(i+j)!=needle.charAt(j))

break;

if(j==nl)

return i;

}

return -1;

}

}

时间： 2024-08-09 22:01:57

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