Function main

Exercises/NoModules/Chapter 17/Soln17_06/Soln17_06.cpp:10–52

#include <utility>

int main()
{
  std::string text;                                // Stores input prose or poem
  std::cout << "Enter a poem or prose over one or more lines.\n"
            << "Terminate the input with #:\n";
  getline(std::cin, text, '#');

  SparseArray<LinkedList<std::string>> lists;      // Sparse array of linked lists
  const std::string_view letters {"ABCDEFGHIJKLMNOPQRSTUVWXYZ"};

  // Extract words and store in the appropriate list
  // A list in the SparseArray is selected by the index in letters of the first letter in a word.
  const std::string_view separators {" \n\t,.\"?!;:"};  // Separators between words
  size_t start {};                                 // Start of a word
  size_t end {};                                   // separator position after a word
  while (std::string::npos != (start = text.find_first_not_of(separators, start)))
  {
    end = text.find_first_of(separators, start+1);
    const auto word{ text.substr(start, end - start) };
    const auto letter{ static_cast<char>(std::toupper(word[0])) };
    lists[letters.find(letter)].push_back(word);
    start = end;
  }

  // List the words in order 5 to a line
  const size_t perline {5};
  
  for (size_t i {}; i < std::size(letters); ++i)
  {
    if (!lists.element_exists_at(i))
      continue;
  
    size_t count {};                               // Word counter
    for (auto iterator { lists[i].front_iterator() }; iterator; iterator.next())
    {
      std::cout << iterator.value() << ' ';
      if (!(++count % perline))
        std::cout << std::endl;
    }
    std::cout << std::endl;
  }
  std::cout << std::endl;
}