28. Implement strStr()

public c
b0f1
lass Solution {
public int strStr(String haystack, String needle) {
if(needle.length()>haystack.length())
return -1;
return haystack.indexOf(needle);
}
}
用String的自带函数
1ms
=======================
public class Solution {
public int strStr(String haystack, String needle) {
if(needle.length()>haystack.length())
return -1;
int lengthh = haystack.length();
int lengthn = needle.length();
int index=0,i,j;
while(lengthh>=lengthn)
{
i=0;
j = index;
int flag = 0;
while(i<lengthn)
{
if(haystack.charAt(j)!=needle.charAt(i))
{
flag = 1;
break;
}
i++;j++;
}
if(flag == 0)
return index;
else
{
index++;lengthh--;
}
}
return -1;
}
}
4ms