FillEmpty.cpp

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

struct food {
public:
  food(){};
  food(const std::string &id, const std::string name,
       const std::uint32_t quantity)
      : id{id}, name{name}, quantity{quantity}, is_empty{false} {};
  food(const std::string &id, const std::string name,
       const std::uint32_t quantity, bool is_empty)
      : id{id}, name{name}, quantity{quantity}, is_empty{is_empty} {};
  food(const food &f)
      : id{f.id}, name{f.name}, quantity{f.quantity}, is_empty{f.is_empty} {};

  std::string id;
  std::string name;
  std::uint32_t quantity;

  bool is_empty;

  static food make_empty() { return {"", "", 0, true}; }
};

std::ostream &operator<<(std::ostream &os, const food &f) {
  os << "["
     << "id: " << f.id << ", "
     << "name: " << f.name << ", "
     << "quantity: " << f.quantity << ", "
     << "is_empty: " << std::boolalpha << f.is_empty << "]";

  return os;
}

int main() {
  auto columns = 4;

  std::vector<food> foods = {
      {"a", "ramen", 1}, {"b", "tsukemen", 2}, {"c", "rice", 3},
      {"d", "soy", 4},   {"e", "chiken", 5},   {"f", "beef", 6},
      {"g", "poke", 7},
  };

  auto empty_cell = columns - foods.size() % columns;

  std::fill_n(std::back_inserter(foods), empty_cell, food::make_empty());

  std::cout << "foods: " << foods.size() << std::endl
            << "empty_cell: " << empty_cell << std::endl;
  for (auto &f : foods) {
    std::cout << f << std::endl;
  }

  return 0;
}