NastenaL

## Compitition
#include <iostream>
using namespace std;

int main() {
	int n, k, j = 0;
	cin>>n>>k;
	int *a = new int[n];
	for ( int i = 0; i < n; i++)	cin>>a[i];
	for (int i = 0; i < n; i++)
	if (a[i] >= a[k-1] && a[i] > 0)   j++;

## Dominoshka
#include <iostream>
#include <cmath>
using namespace std;

int main() {
double N,M;
cin>>N>>M;
cout<<floor(N*M*0.5);
}

## Slider(C#)
using System;
using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace Diploma
{
    public partial class Form1 : Form
    {
        Bitmap RotatingBlocks;

## 123B codeforces.com
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace toys
{
    class Program
    {
	#include <iostream>
	using namespace std;

	int main() {
	int n, k, j = 0;
	cin>>n>>k;
	int *a = new int[n];
	for ( int i = 0; i < n; i++) cin>>a[i];
	for (int i = 0; i < n; i++)
	if (a[i] >= a[k-1] && a[i] > 0) j++;
	#include <iostream>
	#include <cmath>
	using namespace std;

	int main() {
	double N,M;
	cin>>N>>M;
	cout<<floor(NM0.5);
	}
	using System;
	using System.Drawing;
	using System.Windows.Forms;
	using System.Runtime.InteropServices;

	namespace Diploma
	{
	public partial class Form1 : Form
	{
	Bitmap RotatingBlocks;
	using System;
	using System.Collections.Generic;
	using System.Linq;
	using System.Text;
	using System.Threading.Tasks;

	namespace toys
	{
	class Program
	{