#include <iostream>
#include <vector>
 
constexpr unsigned long long factorial(unsigned long long n) {
	return (n <= 1 ? 1 : n*factorial(n-1));
}
 
int main() {
 
	// universal initialization
	std::vector<int> v{1,2,3,4,5,6}; 
 
	// move semantics
	std::vector<int> v2(std::move(v));
 
	// for each loop and auto
	for(auto e: v2) {
		std::cout << e << '\n';
	}
 
	// static assert makes assertions at compile-time
	static_assert(factorial(5) == 120, "factorial(5) should be 120.");
}

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