thrust

◆ is_sorted_until() [3/4]

template<typename DerivedPolicy , typename ForwardIterator , typename Compare >
__host__ __device__ ForwardIterator thrust::is_sorted_until ( const thrust::detail::execution_policy_base< DerivedPolicy > &  exec,
ForwardIterator  first,
ForwardIterator  last,
Compare  comp 
)

This version of is_sorted_until returns the last iterator i in [first,last] for which the range [first,last) is sorted using the function object comp. If distance(first,last) < 2, is_sorted_until simply returns last.

The algorithm's execution is parallelized as determined by exec.

Parameters
execThe execution policy to use for parallelization:
firstThe beginning of the range of interest.
lastThe end of the range of interest.
compThe function object to use for comparison.
Returns
The last iterator in the input range for which it is sorted.
Template Parameters
DerivedPolicyThe name of the derived execution policy.
ForwardIteratoris a model of Forward Iterator and ForwardIterator's value_type is convertible to Compare's argument_type.
Compareis a model of Strict Weak Ordering.

The following code snippet demonstrates how to use is_sorted_until to find the first position in an array where the data becomes unsorted in descending order using the thrust::host execution policy for parallelization:

#include <thrust/sort.h>
...
int A[8] = {3, 2, 1, 0, 3, 2, 1, 0};
int * B = thrust::is_sorted_until(thrust::host, A, A + 8, comp);
// B - A is 4
// [A, B) is sorted in descending order
See also
is_sorted
sort
sort_by_key
stable_sort
stable_sort_by_key