1,"AAAAA" "BB" 从左向右比较"AAAA" 0 - 3 (5-2)
2, stringncmp 实现
int string_ncmp(char * a, char *b, int n){
while(*a && (*a == *b) &&n){
a++;
b++;
--n;
}
if(n == 0)
return 0;
else
return *a - *b;
}
int strStr(char* haystack, char* needle) {
int m = strlen(haystack);
int n = strlen(needle);
if(n > m)
return -1;
for(int i = 0; i <= m-n ; i++){
if(!string_ncmp(haystack+i,needle,n))
return i;
}
return -1;
}
