Question

For some reason, I have to use a stack to achieve some function, but I need to reverse the output stack’s elements. So I want to use stack<char,vector<char> to achieve direct access, but there may be some error in my suggestion. Can anyone tell me how to efficiently reverse the output stack’s elements in C++ using STL stack?

Answer 1

Use a temporary stack.

// On exit the stack 's' will have it's elements reversed.
void reverse_stack(std::stack<int>& s)
{
    std::stack<int> tmp;
    while (!s.empty())
    {
        tmp.push(s.pop());
    }
    s.swap(tmp);
}