Petar Kapriš
2ca5e73a27
Notes: The exercise 2.37 on Hexlet's site has an error, noted in the comments. Also, their page for exercise 2.38 should probably have 0 tests. And finally, I did not calculate the exact number in the final exercise 2.43, but I included a relevant discussion.
21 lines
446 B
Scheme
21 lines
446 B
Scheme
#lang sicp
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(define (accumulate op initial sequence)
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(if (null? sequence)
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initial
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(op (car sequence)
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(accumulate op initial (cdr sequence)))))
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(define (map p sequence)
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(accumulate (lambda (x y) (cons (p x)
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y))
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nil
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sequence))
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(define (append seq1 seq2)
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(accumulate cons seq2 seq1))
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(define (inc x y) (+ y 1))
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(define (length sequence)
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(accumulate inc 0 sequence))
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