Question

How can i conduct std::find on a legacy array without making a new std::vector/std::array from an existing legacy array?

for example:

int ar[N];

if ( std::find(ar, ar + N, value) != &ar[N] ){ /**/ }

Is &ar[N] a valid value for checking the situation when nothing is found? Can I be sure i’m doing right using &ar[N] like an analog of std::vector::end() ?

Answer 1

If you are using c++11, you can use:

int arr[N];
if (std::end(arr) == std::find(std::begin(arr), std::end(arr), value))
{
    // ...
}

For c++98, you can use:

int arr[N];
int *begin = arr;
int *end = begin + N;

if (end == std::find(begin, end, value))
{
    // ...
}