We start by defining atom?, a generic predicate and perm, a helper that will reorder any given list according to the ordering specified in one of its parameters. (perm (map (lambda (x) (permute x order)) lst) This is the idiomatic way to think about a solution in a functional language - we split the problem in sub-problems, solve each one using existing procedures and finally we compose the answer: (define (atom? x) Here's another option, using higher-order functions. Where the ?s represent getting the item based on the first number in ordering and combining this item with the remainder of the calculation, respectively. So a sketch of our solution would look like: (define (permute1 items ordering) This forms the base case (3), the recursive case (1), and the steps to recur deeper (2). If the ordering is the empty list, return the empty list.The rest of the items of the new list will be determined by using the rest of the numbers in the ordering.The first item of the new list will be the 3rd item of items, because the first number in ordering is 3.Now, to calculate (permute1 '(4 5 6) '(3 2 1)), what we mean is: (map (lambda (xs) (permute1 xs ordering)) So we can have a helper permute1 that handles the case of one list, then use map to apply this function to each of the lists (with the same ordering each time): (define (permute lists ordering) We can see that each list in the list of lists can be handled separately, their solutions are unrelated to each other. We are given a list of lists, and a list of numbers, and we want to order each list according to the order specified by the list of numbers: =>(permute '((1 2 3) (4 5 6)) '(3 2 1)) Send us feedback about these examples.Well, let's see how we can break this problem down. These examples are programmatically compiled from various online sources to illustrate current usage of the word 'permutation.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. How To Save A Country, The New Republic, See More 2023 Many of these people are attached to traditional notions of womanhood, traditional notions of family construction, and are deeply uneasy about the liberation movements in all its permutations. 2023 The Lakers, though, vowed not to get caught up in the permutations, focusing instead on controlling the schedule ahead of them. Pranshu Verma, Washington Post, 24 Apr. Lila Kee, Forbes, And experts say contracts more frequently contain fine-print provisions allowing a company to use an actor’s voice in endless permutations, even selling it to other parties. 2023 Our digital identities have seemingly endless permutations through multiple accounts, transactions and credentials. 2022 Depending on the permutation of those dots, that’s what the letter is. Larry Brilliant, Foreign Affairs, 20 Dec. 2023 With 18 hemagglutinin and 11 neuraminidase proteins known, the permutations and combinations are many, leading to a high number of variants. Daniel Drake, The New York Review of Books, 1 Apr. 2023 Each issue observes a theme-reproductive rights, energy, reparations-in its international permutations. jury pool would be hostile to Trump because of the city’s large Black population. Recent Examples on the Web One of its earliest permutations came from Alan Dershowitz, who argued all the way back in 2017, during the Russia investigation, that a D.C.
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