字符串每个字符交错组合

;;字符串每个字符交错组合
;;(BF-Str-Cross "每个字符交" "45678")"每4个5字6符7交8"
(defun BF-Str-Cross(a b / c d str BF-Str->Chrs)
    (defun BF-Str->Chrs(str / a c)
        (setq a(vl-string->list str))
        (while a
            (if(< (car a) 129)
                (setq c (cons (chr (car a)) c) a (cdr a))
                (setq c (cons (strcat (chr (car a)) (chr (cadr a))) c) a (cddr a))
            )
        )
        (reverse c)
    )
    (setq str "" a (BF-Str->Chrs a) b (BF-Str->Chrs b))
    (while (or (car a) (car b))
        (setq c (car a) d (car b) str (strcat str (if c c "") (if d d "")) a (cdr a) b (cdr b))
    )
    str
)