#include <vector>

int main()
{
    std::vector v { 1, 2, 3, 4, 5 };
    // Erase all even numbers (C++11 and later)
    for (auto it = v.begin(); it != v.end();) {
        if (*it % 2 == 0) {
            it = v.erase(it);
        } else {
            ++it;
        }
    }
}