#include <wchar.h>

wchar_t* wcstok(wchar_t* restrict s, const wchar_t* restrict sep, wchar_t** restrict p) {
    if (!s && !(s = *p))
        return NULL;
    s += wcsspn(s, sep);
    if (!*s)
        return *p = 0;
    *p = s + wcscspn(s, sep);
    if (**p)
        *(*p)++ = 0;
    else
        *p = 0;
    return s;
}