#include <iostream>
#include <cstdlib>        //for abs and EXIT_SUCCESS
#include <vector>
#include <algorithm>      //for min_element
#include <functional>     //for ptr_fun
#include <ext/functional> //for compose1
#include "composer_fgx1_gx2.h"
using namespace std;

//Return true if the first argument is nearer to 32 than the second argument is.
inline bool nearer_to_32_func(int a, int b) {return abs(a - 32) < abs(b - 32);}

//Return true if the first argument is nearer to 32 than the second argument is.
class nearer_to {
	const int n;
public:
	nearer_to(int initial_n): n(initial_n) {}
	bool operator()(int a, int b) const {return abs(a - n) < abs(b - n);}
};

int main()
{
	const int a[] = {50, 10, 30, 35, 40};
	const size_t n = sizeof a / sizeof a[0];

	const int *const p = min_element(a, a + n);
	cout << "The smallest number in the array is " << *p << ".\n";

	const vector<int> v(a, a + n);
	vector<int>::const_iterator it = min_element(v.begin(), v.end());
	cout << "The smallest number in the vector is " << *it << ".\n";

	it = min_element(v.begin(), v.end(), nearer_to_32_func);
	cout << "The number that's nearest to 32 is " << *it << ".\n";

	it = min_element(v.begin(), v.end(), nearer_to(32));
	cout << "The number that's nearest to 32 is " << *it << ".\n";

	it = min_element(v.begin(), v.end(),
		compose_fgx1_gx2(
			less<int>(),
			__gnu_cxx::compose1(
				ptr_fun<int, int>(abs),
				bind2nd(minus<int>(), 32))
		)
	);
	cout << "The number that's nearest to 32 is " << *it << ".\n";

	return EXIT_SUCCESS;
}