case the range is reversed back to the lexicographically smallest permutation; otherwise returns true.
nextPermutation
fn
bool nextPermutation(alias less = "a < b", BidirectionalRange)(BidirectionalRange range) if (isBidirectionalRange!BidirectionalRange &&
hasSwappableElements!BidirectionalRange)Permutes range in-place to the next lexicographically greater permutation.
The predicate less defines the lexicographical ordering to be used on the range.
If the range is currently the lexicographically greatest permutation, it is permuted back to the least permutation and false is returned. Otherwise, true is returned. One can thus generate all permutations of a range by sorting it according to less, which produces the lexicographically least permutation, and then calling nextPermutation until it returns false. This is guaranteed to generate all distinct permutations of the range exactly once. If there are N elements in the range and all of them are unique, then N! permutations will be generated. Otherwise, if there are some duplicated elements, fewer permutations will be produced. ---- // Enumerate all permutations int[] a = [1,2,3,4,5]; do { // use the current permutation and // proceed to the next permutation of the array. } while (nextPermutation(a)); ----
Parameters
less | The ordering to be used to determine lexicographical ordering of the permutations. |
range | The range to permute. |
Returns
false if the range was lexicographically the greatest, in which