ex10_34_35_36_37.cpp

// @Alan @pezy
//
// Exercise 10.34:
// Use reverse_iterators to print a vector in reverse order.
//
// Exercise 10.35:
// Now print the elements in reverse order using ordinary iterators.
//
// Exercise 10.36:
// Use find to find the last element in a list of ints with value 0.
//
// Exercise 10.37:
// Given a vector that has ten elements, copy the elements from positions
// 3 through 7 in reverse order to a list.
//

#include <iostream>
#include <algorithm>
#include <list>
#include <vector>
#include <iterator>

int main()
{
    std::vector<int> vec = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };

    // 10.34
    for (auto rit = vec.crbegin(); rit != vec.crend(); ++rit)
        std::cout << *rit << " ";
    std::cout << std::endl;

    // 10.35
    for (auto it = std::prev(vec.cend()); true; --it) {
        std::cout << *it << " ";
        if (it == vec.cbegin()) break;
    }
    std::cout << std::endl;

    // 10.36
    std::list<int> lst = { 1, 2, 3, 4, 0, 5, 6 };
    auto found_0 = std::find(lst.crbegin(), lst.crend(), 0);
    std::cout << std::distance(found_0, lst.crend()) << std::endl;

    // 10.37
    std::list<int> ret_lst;
    std::copy(vec.crbegin() + 3, vec.crbegin() + 8, std::back_inserter(ret_lst));
    //     0, 1, 2, 3, 4, 5, 6, 7, 8, 9
    //    ^                  ^
    // rend                  rbegin
    // @note: std::copy copies the range [first, last) into result.
    //        hence, the arguments here denote:
    //        [6 5 4 3 2 1)
    //                   ^ this one is specified but not included.
    for (auto i : ret_lst) std::cout << i << " ";
    std::cout << std::endl;
}