C++ algorithm count_if

Table of contents

  std::array<int, 4> arr{ 1, 2, 3, 4 };

  auto res = std::count_if( arr.cbegin(), arr.cend(), []( int x ) { return x == 3; } );
  std::cout << "There are " << res << " number of elements equal to 3" << std::endl;

Possible output

There are 1 number of elements equal to 3