How do I change the list using mutable lists in Racket or Scheme?

Posted by exOne on Stack Overflow See other posts from Stack Overflow or by exOne
Published on 2011-01-18T00:57:11Z Indexed on 2011/01/18 2:53 UTC
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Scheme

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racket

I need your help Can anyone help me?

first question

This procedure should modify each element which’s index in the list is even. The value of the element should be equal to the new-element. For example: (define number-list (1 56 8 1 43 9 78)) (modify-even-indices number-list 10) The new list: 1 10 8 10 43 10 78

second question

This problem is the extended version of Question 1.

(modify-even-odd-indices my-list new-element modification-type) This procedure should modify each element according to the modification-type. The modification-type can be even or odd. For example: (define number-list (1 56 8 1 43 9 78)) (modify-even-odd-indices number-list 10 ‘even’) The new list: 1 10 8 10 43 10 78 (modify-even-odd-indices number-list 10 ‘odd’) The new list: 10 56 10 1 10 9 10

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