ex10_18_19.cpp

//!
//! @author @Yue Wang @pezy
//! @date   12.10.2014
//!
//! Exercise 10.18:
//! Rewrite biggies to use partition instead of find_if.
//!
//! Exercise 10.19:
//! Rewrite the previous exercise to use stable_partition, which like
//! stable_sort maintains the original element order in the paritioned
//! sequence.
//!

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

//! from ex 10.9
void elimdups(std::vector<std::string>& vs)
{
    std::sort(vs.begin(), vs.end());
    auto new_end = std::unique(vs.begin(), vs.end());
    vs.erase(new_end, vs.end());
}

//! ex10.18
void biggies_partition(std::vector<std::string>& vs, std::size_t sz)
{
    elimdups(vs);

    auto pivot = partition(vs.begin(), vs.end(), [sz](const std::string& s) {
        return s.size() >= sz;
    });

    for (auto it = vs.cbegin(); it != pivot; ++it) std::cout << *it << " ";
}

//! ex10.19
void biggies_stable_partition(std::vector<std::string>& vs, std::size_t sz)
{
    elimdups(vs);

    auto pivot =
        stable_partition(vs.begin(), vs.end(),
                         [sz](const std::string& s) { return s.size() >= sz; });

    for (auto it = vs.cbegin(); it != pivot; ++it) std::cout << *it << " ";
}

int main()
{
    //! ex10.18
    std::vector<std::string> v{"the",  "quick", "red",  "fox", "jumps",
                               "over", "the",   "slow", "red", "turtle"};

    std::cout << "ex10.18: ";
    std::vector<std::string> v1(v);
    biggies_partition(v1, 4);
    std::cout << std::endl;

    //! ex10.19
    std::cout << "ex10.19: ";
    std::vector<std::string> v2(v);
    biggies_stable_partition(v2, 4);
    std::cout << std::endl;

    return 0;
}
//! output :
//!
// ex10.18: turtle jumps over quick slow
// ex10.19: jumps over quick slow turtle