1. zadatak


#include <iostream>
#include <fstream>



using namespace std;



int main()
{


	ofstream out("res.txt");
	if (!out)
	{
		cout << "nije moguce" << endl;
		return 1;
	}



	double rad;
	cout << "Radijus:";
	cin >> rad;

	double v = 4 * 3.14 * pow(rad, 3) / 3;
	double p = 4 * 3.14 * pow(rad, 2);


	out << "Radijus:" << rad << endl;
	out << "Volumen:" << v << endl;
	out << "Povrsina:" << p << endl;




	out.close();
	return 0;

}


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2. zadatak


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

bool prost(int broj)
{

	if (broj == 1)
	{
		return false;
	}
	for (int i = 2; i <= broj/2; i++)
	{
		if (broj % i ==0)
		{
			return false;
		}
	}
	return true;
}

int main() {


	ifstream in("tekst.txt");
	ofstream out("prosti.txt");
	if (!in||!out)
	{
		cout << "can't do" << endl;
		return 1;
	}

	
	int broj;
	while (in >> broj)
	{
		if (prost(broj))
		{
			out << broj << endl;
		}
	}
	
	
	in.close();
	out.close();
	return 0;
}

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3. zadatak 



#include <iostream>
#include <fstream>
#include <vector>
using namespace std;



int main() {


	ifstream in("tekst.txt");
	ofstream parni("parni.txt");
	ofstream neparni("neparni.txt");
	if (!in||!parni||!neparni)
	{
		cout << "can't do" << endl;
		return 1;
	}

	vector <int> v;
	int broj;
	while (in >> broj)
	{
		v.push_back(broj);
	}


	for (int i = v.size()-1; i >= 0; i--)
	{
		if (v[i] % 2 == 0)
		{
			parni << v[i] << endl;
		}
		else
		{
			neparni << v[i] << endl;
		}
	}


	in.close();
	parni.close();
	neparni.close();
	return 0;
}