#include<iostream>
#include<vector>
#include<string>

namespace StringProcessing
{
    std::string getStrByPrefix(const std::vector<size_t> & prefix_function)
    {
        if (!prefix_function.size())
        {
            return "";
        }
        std::string str = "a";

        for (size_t i = 1; i < prefix_function.size(); i++)
        {
            if (prefix_function[i] != 0)
            {
                str += str[prefix_function[i] - 1];
            }
            else
            {
                std::vector<bool> used(26, false);
                size_t k = prefix_function[i - 1];
                while (k > 0)
                {
                    used[str[k] - 'a'] = true;
                    k = prefix_function[k - 1];
                }
                char curr_symb = 'b';
                while (used[curr_symb - 'a'])
                {
                    curr_symb++;
                };
                str += curr_symb;
            }
        }
        return str;
    }
}


int main()
{
    size_t n;
    std::cin >> n;
    std::vector<size_t> prefix_function(n);
    for (size_t i = 0; i < n; i++)
    {
        std::cin >> prefix_function[i];
    }
    std::cout << StringProcessing::getStrByPrefix(prefix_function);

}