// Illustrate various simple uses of auto i C++11

#include <iostream>    
#include <vector>
#include <cmath>    // abs
#include "point.h"



// Illustration of alternative return type - best if return type depends on parameters.
auto find_diagonal_points(std::vector<Point> points) -> std::vector<Point>{
  std::vector<Point> res;
  for(auto p: points)
    if(std::abs(p.getx())==std::abs(p.gety()))
      res.push_back(p);
  return res;
}

void without_auto(){
  int i{5};

  std::vector<Point> points = {Point{1,1}, Point{1,2}, Point{-1,1}, Point{-2,2}};
  std::vector<Point> diagonal_points = find_diagonal_points(points);
  for(Point p: diagonal_points)
    std::cout << p << std::endl;
}

void with_auto(){
  auto i = 5;       // initialize auto's with =, not {}.

  auto points = std::vector<Point>{{Point{1,1}, Point{1,2}, Point{-1,1}, Point{-2,2}}};
  auto diagonal_points = find_diagonal_points(points);
  for(auto p: diagonal_points)
    std::cout << p << std::endl;
}

int main () {
  without_auto();
  std::cout << std::endl;
  with_auto();
}