FILE 1:

#include <iostream>
#include <string>
#include <utility>
#include <vector>

using namespace std;

class sample {
	// the container holding all the samples
	vector<double> samples;
	
public:
	sample(vector<double> vd) : samples(vd) {}
};

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FILE 2

#include <iostream>
#include <utility>
#include <string>
#include <vector>
#include "sample.h"

using namespace std;

ostream& operator<<(ostream &s, sample &p) {
	s << "<" << p[0] << ":";
	
	for (int i = 1; i <= p.size() - 1; i++)
		s << p[i] << " ";
	
	s << ">";
}

int main() {
	vector<double> vd(5);
	vd[0] = 0;
	vd[1] = 1.0;
	vd[2] = 2.0;
	sample s = vd;
	cout << s;
}