function template
<algorithm>

std::find_if_not

template <class InputIterator, class UnaryPredicate>
   InputIterator find_if_not (InputIterator first, InputIterator last, UnaryPredicate pred);
Find element in range (negative condition)
Returns an iterator to the first element in the range [first,last) for which pred returns false. If no such element is found, the function returns last.

The behavior of this function template is equivalent to:
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template<class InputIterator, class UnaryPredicate>
  InputIterator find_if_not (InputIterator first, InputIterator last, UnaryPredicate pred)
{
  while (first!=last) {
    if (!pred(*first)) return first;
    ++first;
  }
  return last;
}


Parameters

first, last
Input iterators to the initial and final positions in a sequence. The range used is [first,last), which contains all the elements between first and last, including the element pointed by first but not the element pointed by last.
pred
Unary function that accepts an element in the range as argument and returns a value convertible to bool. The value returned indicates whether the element is considered a match in the context of this function.
The function shall not modify its argument.
This can either be a function pointer or a function object.

Return value

An iterator to the first element in the range for which pred returns false.
If pred is true for all elements, the function returns last.

Example

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// find_if_not example
#include <iostream>     // std::cout
#include <algorithm>    // std::find_if_not
#include <array>        // std::array

int main () {
  std::array<int,5> foo = {1,2,3,4,5};

  std::array<int,5>::iterator it =
    std::find_if_not (foo.begin(), foo.end(), [](int i){return i%2;} );
  std::cout << "The first even value is " << *it << '\n';

  return 0;
}


Output:
The first even value is 2

Complexity

Up to linear in the distance between first and last: Calls pred for each element until a mismatch is found.

Data races

Some (or all) of the objects in the range [first,last) are accessed (once at most).

Exceptions

Throws if either pred or an operation on an iterator throws.
Note that invalid parameters cause undefined behavior.

See also

find_if
Find element in range (function template )
mismatch
Return first position where two ranges differ (function template )
none_of
Test if no elements fulfill condition (function template )

C++