#include <vector>
#include <stdexcept>

std::int32_t findIndex(std::vector<std::int32_t>& v, std::int32_t x)
{
    try
    {
        std::size_t = v.size();
        for ( std::size_t i = 0U; i < size; ++i)
        {
            if( v.at(i) == x)
            {
                throw i;
            }
        }

    }
    catch (std::size_t foundIdx)
    {
        return foundIdx;
    }
    catch(std::out_of_range& e)
    {
        return -1;
    }

    return -1;
}