How to not land a job.

	// Whatever you do, when asked to enumerate permutations of length n,
	// don't demonstrate that you can quickly produce this solution...
	#include <algorithm>
	#include <cerrno>
	#include <cstdlib>
	#include <iostream>
	#include <iterator>
	#include <numeric>
	#include <stdexcept>
	#include <vector>
	int main(int argc, char *argv[])
	{
	using namespace std;
	// Parse incoming single command line argument
	if (argc != 2) throw invalid_argument("argc != 2");
	errno = 0;
	char *end;
	const unsigned long n = strtoul(argv[1], &end, 10);
	if (errno || end == argv[1]) throw invalid_argument(argv[1]);
	// Output the requested permutations
	vector<unsigned long> s(n, 1);
	partial_sum(s.begin(), s.end(), s.begin());
	do {
	copy(s.begin(), s.end(), ostream_iterator<unsigned long>(cout, " "));
	cout << '\n';
	} while (next_permutation(s.begin(), s.end()));
	return EXIT_SUCCESS;
	}
	// ...but instead mumble briefly about how next_permutation works,
	// worry about the algorithmic internals of std::next_permutation for 10
	// minutes in front of a blank whiteboard. Ultimately produce nothing. And
	// then ask the interviewer to please move on.

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