题目:https://leetcode.com/problems/implement-strstr/tabs/description/
代码:
class Solution {
public:
int strStr(string a, string b) {
int i,j,len1=a.size(),len2=b.size();
if(!len2) return 0;
if(len2>len1) return -1;
for(i=0;i<len1-len2+1;i++){
for(j=0;j<len2;j++){
if(a[i+j]!=b[j]) break;
}
if(j==len2) return i;
}
if(i==len1-len2+1) return -1;
}
};