c-链表，在前面插入一个节点

Question

给定一个包含链表的对象，当我无法返回该链表的内存地址时，如何将新节点添加到该链表的头部？

struct group {
    char *name;
    struct user *users;
    struct xct *xcts;
    struct group *next;
};
struct user {
    char *name;
    double balance;
    struct user *next;
};

Answer 1

它比你想象的要简单得多：

usr->next = group->users;
group->users = usr;