Re: Lower number/bound
Shimon Shvartsbroit wrote:
This can be very easily accomplished if you make sure the array is
sorted in ascending order, as it is in your example.
#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
void main()
{
typedef std::vector<int> MyArray;
int tmp[] = {1,4, 10, 15 , 20 , 30 };
MyArray arr(tmp, tmp + sizeof(tmp) / sizeof(tmp[0]));
// sort in asecnding order, in case it's not sorted
std::sort(arr.begin(), arr.end());
// find the first value that is less or equal to 25.. the search is
done from the end of container to its begining
MyArray::reverse_iterator it = std::find_if(arr.rbegin(), arr.rend(),
std::bind2nd(std::less_equal<int>(), 25));
if (it!=arr.rend())
{
// here is the value of the found item
std::cout << *it << std::endl;
}
}
lower_bound and upper_bound won't do in this case. But hey, it's so
easy to use predicates in STL algorithms :-)
While the question "Why aren't you using vectors?" is valid, it is worth
noting, in my opinion, that pointers themselves can act as iterators and
be passed directly to the standard algorithms.
int tmp[] = {1, 4, 10, 15, 20, 30};
unsigned int size = 6; // size of the array
std::sort(tmp, tmp + size);
int *val = std::upper_bound(tmp, tmp + size, 25);
Jack Saalweachter