// lambda.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
#include <memory>
#include <map>
#include <algorithm>

using namespace std;


void print(int i)
{
	cout << i << endl;
};


int main()
{

	vector <int> vi; //reminder about the vector
	vi.push_back(1);
	vi.push_back(2);
	vi.push_back(3);
	vi.push_back(4);
	vi.push_back(5);
	vi.push_back(6);


	for_each(vi.begin(), vi.end(), print); //usual way of printing the vector elements
	cout << "__________________________________________" << endl;
	
	//Lambda example

	for_each(vi.begin(), vi.end(), [](int k) { cout << k << endl; }); //Square brackets say that it is a lambda function, round brackets say that lambda takes integers as parameter and braces say what we are going to do

	cout << "__________________________________________" << endl;

	for_each(vi.begin(), vi.end(), //exactly the same function but written in multiple lines
		[](int k)
	{
		cout << k << endl;
	}
	);

	cout << "__________________________________________" << endl;

	for_each(vi.begin(), vi.end(), //lambda funciton with multiple statements
		[](int k)
	{
		if (k % 3 == 0)
		{
			cout << k << " is divisible by 3" << endl;
		}
		else
		{
			cout << k << " is not divisible by 3" << endl;
		}

	}
	);

	cout << "__________________________________________" << endl;

	//Lambdas with return type

	vector<int> v2;
	transform(vi.begin(), vi.end(), back_inserter(v2), [](int k) {return k * k; }); //Lambda that returns, transform take one collection and transform to another collection, back_inserted push back the elements to the new vector

																					//This lambda is easy for compiler to figure out  the type of the return -> we do not need to specify it explicitly

	for_each(v2.begin(), v2.end(),
		[](int k)
	{
		cout << k << endl;
	}
	);

	vector<double> v3;
	transform(vi.begin(), vi.end(), back_inserter(v3), [](int k)->double
	{
		if (k % 2 == 0)
		{
			return k * k;
		}
		else
		{
			return k * k / 2.0;
		}
	}
	); //Lambda that returnsm where we need to specify the return type



	for_each(v3.begin(), v3.end(),
		[](double s)
	{
		cout << s << endl;
	}
	);

	system("pause");
	return 0;
}