c - 我的 strchr 版本有什么问题？

Question

我的任务是编写我自己的 strchr 版本，但它似乎不起作用。任何建议将不胜感激。这是:

char *strchr (const char *s, int c) //we are looking for c on the string s
{

    int dog; //This is the index on the string, initialized as 0
    dog = 0;
    int point; //this is the pointer to the location given by the index
    point = &s[dog];
    while ((s[dog] != c) && (s[dog] != '\0')) { //it keeps adding to dog until it stumbles upon either c or '\0'
            dog++;
            }
    if (s[dog]==c) {
            return point; //at this point, if this value is equal to c it returns the pointer to that location
            }
    else {
            return NULL; //if not, this means that c is not on the string
            }
}

Answer 1

您正在尝试将地址存储到point中但它是一个 int 变量。你应该做这样的事情:

char *strchr(char *s, char c) {
    int pos = 0;
    while (s[pos] != c && s[pos] != '\0')
        pos++;
    if (s[pos] == c)
        return &s[pos];
    else
        return NULL;
}

顺便说一下:s应该是char *不是const char *因为你返回一个指向 char 的指针，这不是一个好的风格;)(或返回const char *)