c .16.链接，比较代码讲解,分治策略与递归

char* my_strcat(char* dist, const char* src)
{
    if (dist == nullptr || src == nullptr)
    {
        return dist;
    }
    char* cp = dist;
    while (*cp != ‘\0‘) { ++cp; }
    while (*cp = *src)
    {
        cp++;
        src++;
    }
    return dist;
}

int main()
{
    char stra[30] = {"yhping"};
    char strb[30] = {"hello"};
    char strc[30] = {};

    my_strcat(stra, strb);
    printf("stra = %s \n", stra);
    // stra => "yhpinghello";
    // strb =>"hello";
}

1.int my_strcmp(const char* first, const char* second)
{
    assert(first != nullptr && second != nullptr);
    int k = 0;
    while ((k = *first - *second) == 0 && *first++ && *second++);//比较的优先级高于逻辑的优先级
    return k;
}
//yhping                      yhpa                        yhping
//yhping    相同，直到\0退出    yhping  a小于i，小于0，退出    yhpa    i大于a，大于0，退出   
2.int my_strcmp(const char* first, const char* second)
{
    assert(first != nullptr && second != nullptr);
    while (*first != ‘\0‘ && *second != ‘\0‘)
    {
        if (*first != *second)
        {
            break;
        }
    }
    return *first - *second;
}

int main()
{
    char stra[30] = {"yhping"};
    char strb[30] = {"yhp"};
    char strc[30] = {};

int main()                              
{
    char stra[] = { "yhping" };
    char strb[] = { "yhping" };

    char* strc = "yhping";//加const称为静态常量
    char* strd = "yhping";//为字符串常量

    bool x = (stra == strb);
    bool y = (strc == strd);
    // x  // y;
    stra[0] = ‘x‘; // ok//stra已近给x开辟空间，可以改变y为x
    //strc[0] = ‘x‘; // error;//strc指向的是字符串常量只允许读值不允许改值

    return 0;
}