منابع مشابه
Generating Permutations of a Bag by Interchanges
We present algorithms for generating all permutations of a given bag so that successive permutations diier by the interchange of two elements. One version of the algorithm runs in time linear in the number of permutations.
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We consider permutations of {1, 2, . . . , n} in which each integer is given a direction; such permutations are called directed permutations. An integer k in a directed permutation is called mobile of its arrow points to a smaller integer adjacent to it. For example, for → 3 → 2 ← 5 → 4 → 6 → 1 , the integers 3, 5, and 6 are mobile. It follows that 1 can never be mobile since there is no intege...
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Given (n; k) with n k 2 and k 6 = 3, we show how to generate all permutations of n objects (each exactly once) so that successive permutations diier in exactly k positions, as do the rst and last permutations. This solution generalizes known results for the speciic cases where k = 2 and k = n. When k = 3, we show that it is possible to generate all even (odd) permutations of n objects so that s...
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ژورنال
عنوان ژورنال: The Computer Journal
سال: 1978
ISSN: 0010-4620,1460-2067
DOI: 10.1093/comjnl/21.4.302