Find largest and second largest element in a range

Question

How do I find the above without removing the largest element and searching again? Is there a more efficient way to do this? It does not matter if the these elements are duplicates.

Answer 1

using partial_sort ?

std::partial_sort(aTest.begin(), aTest.begin() + 2, aTest.end(), Functor);

An Example:

std::vector<int> aTest;

    aTest.push_back(3);
    aTest.push_back(2);
    aTest.push_back(4);
    aTest.push_back(1);


    std::partial_sort(aTest.begin(), aTest.begin()+2,aTest.end(), std::greater<int>());

    int Max = aTest[0];
int SecMax = aTest[1];