// algorithms

// demonstrate sort, 

#include <iostream>
#include <string>
#include <vector>
#include <cstdlib>
#include <algorithm>
using namespace std;

void show( vector<int> & v )
{
	vector<int>::iterator I = v.begin( );

	while( I != v.end( ) )
	{
		cout << *I << ", ";
		I++;
	}
	cout << endl;
}

void sortAscending( vector<int> & v )
{
	vector<int>::iterator B = v.begin( );
	vector<int>::iterator E = v.end( );

	cout << "Sorting in ascending order..." << endl;
	sort( B, E );
	show( v );
}

bool gtrThan( int X, int Y )
{ return X > Y; }

void sortDescending( vector<int> & v )
{
	vector<int>::iterator B = v.begin( );
	vector<int>::iterator E = v.end( );

	cout << "Sorting in descending order..." << endl;
	sort( B, E, gtrThan );
	show( v );
}


void findExample( vector<int> & v )
{
	vector<int>::iterator where;

	where = find( v.begin( ), v.end( ), 58 );

	if( where == v.end( ) )
		cout << "Value not found" << endl;
	else
		cout << "Value found: " << *where << endl;
}

bool pred( int X )
{
	return X > 50;
}

void countExample( vector<int> & v )
// count the number of elements that cause the
// pred() function to return true.
{
	int n = count_if( v.begin( ), v.end( ), pred );
	cout << "count_if: " << n << endl;
}

void randomShuffle( vector<int> & v )
// shuffle elements randomly
{
	cout << "Randomly shuffling elements...\n";
	random_shuffle( v.begin( ), v.end( ) );
	show( v );
}


void printSquare( int x )
// displays the square of each value
{ 
	cout << x * x << ", ";
}

void forEachExample( vector<int> & v )
{
	cout << "Calling printSquare for each element:\n";
	for_each( v.begin( ), v.end( ), printSquare );
	cout << endl;
}


int main()
{
	vector<int> v;
	for( int i = 0; i < 10; i++ )
		v.push_back( rand( ) % 100 );

	cout << "Original order...\n";
	show( v );
	
	//sortAscending( v );
	//sortDescending( v );
	//randomShuffle( v );
	//findExample( v );
	//countExample( v );
	forEachExample( v );

	return 0;
}