#include <algorithm>
#include <iostream>

int main()
{
  const char *str = "abcddddefgh";

  std::pair<const char*, const char*> bereich = std::equal_range(str, str+11, 'd');
  std::cout << str << '\n'
            << "   "    << bereich.first  << '\n'
            << "   ^^^" << bereich.second << '\n';
}