(define (make-rat n d)
(cond
((and (< n 0) (< d 0)) (cons (* -1 n) (* -1 d)))
((and (> n 0) (< d 0)) (cons (* -1 n) (* -1 d)))
((and (< n 0) (< d 0)) (cons n (* -1 d) ))
((= d 0) (cons 0 0 ))
((= n 0) (cons n d ))
(else (cons n d)))
)
(define (make-rat n d)
(cond
((and (= n 0) (< d 0)) (cons n (* -1 d)))
((= d 0) (error "divided by Zero"))
((= n 0) (cons n d ))
((< d 0) (cons (* -1 n) (* -1 d)))
(else (cons n d)))
)
(define (make-rat n d)
(cond
((and (= n 0) (< d 0)) (cons n (* -1 d)))
((= d 0) (error "Divided by Zero"))
((< d 0) (cons (* -1 n) (* -1 d)))
(else (cons n d)))
)
(make-rat 1 1)
(make-rat -1 1)
(make-rat 1 -1)
(make-rat -1 -1)
(make-rat 0 -1)
(make-rat -1 0)
(make-rat 0 0)