Template Function thrust::unique_copy(InputIterator, InputIterator, OutputIterator)¶
Function Documentation¶
-
template<typename
InputIterator
, typenameOutputIterator
>
OutputIteratorthrust
::
unique_copy
(InputIterator first, InputIterator last, OutputIterator result) unique_copy
copies elements from the range[first, last)
to a range beginning withresult
, except that in a consecutive group of duplicate elements only the first one is copied. The return value is the end of the range to which the elements are copied.The reason there are two different versions of unique_copy is that there are two different definitions of what it means for a consecutive group of elements to be duplicates. In the first version, the test is simple equality: the elements in a range
[f, l)
are duplicates if, for every iteratori
in the range, eitheri == f
or else*i == *(i-1)
. In the second, the test is an arbitraryBinaryPredicate
binary_pred:
the elements in[f, l)
are duplicates if, for every iteratori
in the range, eitheri == f
or elsebinary_pred(*i, *(i-1))
istrue
.This version of
unique_copy
usesoperator==
to test for equality.The following code snippet demonstrates how to use
unique_copy
to compact a sequence of numbers to remove consecutive duplicates.- Return
The end of the unique range
[result, result_end)
.- Pre
The range
[first,last)
and the range[result, result + (last - first))
shall not overlap.- Parameters
first
: The beginning of the input range.last
: The end of the input range.result
: The beginning of the output range.
- Template Parameters
InputIterator
: is a model of Input Iterator, andInputIterator's
value_type
is a model of Equality Comparable.OutputIterator
: is a model of Output Iterator and andInputIterator's
value_type
is convertible toOutputIterator's
value_type
.
#include <thrust/unique.h> ... const int N = 7; int A[N] = {1, 3, 3, 3, 2, 2, 1}; int B[N]; int *result_end = thrust::unique_copy(A, A + N, B); // The first four values of B are now {1, 3, 2, 1} and (result_end - B) is 4 // Values beyond result_end are unspecified
- See
unique
- See