(在列表结构上实现这种自同构的Scheme函数:)(define(RotateHandshakes 180 a)(RotateHandshakes\u n_steps a(count pars a)))
(define(count pars a)(如果(不是(配对?a) )0(+1(计数PAR(a车))(计数PAR(cdr a)))))
(define(RotateHandshakes a)(如果(null?a) (列表)(附加(a部分)(列表(cdr a))))
(define(RotateHandshakes_u n_u u n_u u n峎n峎n峈)(如果(零?n) a(旋转手柄摇动步数(旋转手柄a)(-1+n)))
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