23 lines
No EOL
572 B
Scheme
23 lines
No EOL
572 B
Scheme
#lang sicp
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;the setup
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(define (make-vect x y) (cons x y))
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(define (xcor-vect v) (car v))
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(define (ycor-vect v) (cdr v))
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(define (add-vect u v)
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(make-vect (+ (xcor-vect u) (xcor-vect v))
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(+ (ycor-vect u) (ycor-vect v))))
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(define (sub-vect u v)
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(make-vect (- (xcor-vect u) (xcor-vect v))
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(- (ycor-vect u) (ycor-vect v))))
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(define (scale-vect s v)
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(make-vect (* s (xcor-vect v))
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(* s (ycor-vect v))))
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;the exercise
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(define (make-segment v1 v2) (cons v1 v2))
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(define (start-segment s) (car s))
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(define (end-segment s) (cdr s)) |