Template Function thrust::upper_bound(ForwardIterator, ForwardIterator, const T&, StrictWeakOrdering)

Function Documentation

template<class ForwardIterator, class T, class StrictWeakOrdering>
ForwardIterator thrust::upper_bound(ForwardIterator first, ForwardIterator last, const T &value, StrictWeakOrdering comp)

upper_bound is a version of binary search: it attempts to find the element value in an ordered range [first, last). Specifically, it returns the last position where value could be inserted without violating the ordering. This version of upper_bound uses function object comp for comparison and returns the furthermost iterator i in [first, last) such that, for every iterator j in [first, i), comp(value, *j) is false.

The following code snippet demonstrates how to use

upper_bound to search for values in a ordered range.
Return

The furthermost iterator i, such that comp(value, *i) is false.

Parameters

  • first: The beginning of the ordered sequence.

  • last: The end of the ordered sequence.

  • value: The value to be searched.

  • comp: The comparison operator.

Template Parameters

#include <thrust/binary_search.h>
#include <thrust/device_vector.h>
#include <thrust/functional.h>
...
thrust::device_vector<int> input(5);

input[0] = 0;
input[1] = 2;
input[2] = 5;
input[3] = 7;
input[4] = 8;

thrust::upper_bound(input.begin(), input.end(), 0, thrust::less<int>()); // returns input.begin() + 1
thrust::upper_bound(input.begin(), input.end(), 1, thrust::less<int>()); // returns input.begin() + 1
thrust::upper_bound(input.begin(), input.end(), 2, thrust::less<int>()); // returns input.begin() + 2
thrust::upper_bound(input.begin(), input.end(), 3, thrust::less<int>()); // returns input.begin() + 2
thrust::upper_bound(input.begin(), input.end(), 8, thrust::less<int>()); // returns input.end()
thrust::upper_bound(input.begin(), input.end(), 9, thrust::less<int>()); // returns input.end()

See

http://www.sgi.com/tech/stl/upper_bound.html

See

lower_bound

See

equal_range

See

binary_search