template <class InputIterator, class Predicate>
bool all_of(InputIterator first, InputIterator last, Predicate pred);
template <class ExecutionPolicy, class InputIterator, class Predicate>
bool all_of(ExecutionPolicy&& exec, InputIterator first, InputIterator last,
Predicate pred);
Returns: true if [first, last) is empty or if pred(*i) is true for every iterator i in the range [first, last), and false otherwise.
Complexity: At most last - first applications of the predicate.