```
template<class InputIterator, class Function>
Function for_each(InputIterator first, InputIterator last, Function f);
```

Requires: Function shall meet the requirements of MoveConstructible. [ Note: Function need not meet the requirements of CopyConstructible. — end note ]

Effects: Applies f to the result of dereferencing every iterator in the range [first, last), starting from first and proceeding to last - 1. [ Note: If the type of first satisfies the requirements of a mutable iterator, f may apply non-constant functions through the dereferenced iterator. — end note ]

```
template<class ExecutionPolicy, class ForwardIterator, class Function>
void for_each(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last,
Function f);
```

Effects: Applies f to the result of dereferencing every iterator in the range [first, last). [ Note: If the type of first satisfies the requirements of a mutable iterator, f may apply non-constant functions through the dereferenced iterator. — end note ]

Remarks: If f returns a result, the result is ignored. Implementations do not have the freedom granted under [algorithms.parallel.exec] to make arbitrary copies of elements from the input sequence.

[ Note: Does not return a copy of its Function parameter, since parallelization may not permit efficient state accumulation. — end note ]

```
template<class InputIterator, class Size, class Function>
InputIterator for_each_n(InputIterator first, Size n, Function f);
```

Requires: Function shall meet the requirements of MoveConstructible [ Note: Function need not meet the requirements of CopyConstructible. — end note ]

Effects: Applies f to the result of dereferencing every iterator in the range [first, first + n) in order. [ Note: If the type of first satisfies the requirements of a mutable iterator, f may apply non-constant functions through the dereferenced iterator. — end note ]

```
template<class ExecutionPolicy, class ForwardIterator, class Size, class Function>
ForwardIterator for_each_n(ExecutionPolicy&& exec, ForwardIterator first, Size n,
Function f);
```

Effects: Applies f to the result of dereferencing every iterator in the range [first, first + n). [ Note: If the type of first satisfies the requirements of a mutable iterator, f may apply non-constant functions through the dereferenced iterator. — end note ]

Remarks: If f returns a result, the result is ignored. Implementations do not have the freedom granted under [algorithms.parallel.exec] to make arbitrary copies of elements from the input sequence.