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

int main() {
	// your code goes here
	int a,d,b;
	float p;
	cout << "Vnesi strana na pravoagolnikot:\n";
	cin >>a;
	cout << "Vnesi dijagonala na pravoagolnikot:\n";
	cin >>d;

	b=sqrt(pow(d,2) - pow(a,2));

            cout<<"Plostinata na pravoagolnikt e:"<<a*b;

	return 0;
}