#define _CRT_SECURE_NO_WARNINGS 1
#include
#include
#include
 
char *my_strstr(const char *dst,const  char *src)
{
    assert(dst);
    assert(src);
    char *p = dst;
    char *s1 = p;
    char *s2 = src;
    while (*s1)
    {
        s1 = p;
        s2 = src;
        while ((*s1!='\0')&&(*s2 != '\0'))
        {
            if (*s1++ == *s2++)
            {
                ;
            }
            else
            {    
                p++;
                break;
            }
        }
        if (*s2 == '\0')
        {
            return p;
        }
     
    }
}
 
int main()
{
    char *str1 = "abbbcdef";
    char *str2 = "bbcd";
    char *ret = my_strstr(str1, str2);
    printf("%s\n", ret);
    system("pause");
    return 0;
}

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