#include <iostream>
#include <cstdlib>
#include <vector>
#include <stdexcept>   //for out_of_range
using namespace std;

int main()
{
	int a[] = {10, 20, 30};
	const size_t n = sizeof a / sizeof a[0];
	vector<int> v(a, a + n);

	cout << "Please input a subscript: ";
	vector<int>::size_type i;   //data type for a vector subscript
	cin >> i;

	try {
		cout << "Element number " << i << " is " << v.at(i) << ".\n";
	}

	catch (const out_of_range& out) {
		cerr << "caught out_of_range exception " << out.what() << "\n";
		return EXIT_FAILURE;
	}

	catch (const exception& e) {
		cerr << "caught another exception " << e.what() << "\n";
		return EXIT_FAILURE;
	}

	catch (...) {
		cerr << "caught unexpected exception\n";
		return EXIT_FAILURE;
	}

	for (vector<int>::size_type i = 0; i < v.size(); ++i) {
		cout << v[i] << "\n";   //cout << v.operator[](i) << "\n";
	}

	for (vector<int>::const_iterator it = v.begin(); it != v.end(); ++it) {
		cout << *it << "\n";    //cout << it.operator*() << "\n";
	}

	return EXIT_SUCCESS;
}