Use transform(map) function to modify the elements in a container. [C++]

update_all_elements_in_vector.cc

#include <algorithm>
#include <iostream>
#include <iterator>
#include <vector>

int main() {
  auto v = std::vector<int> {1, 2, 3};

  // Use transform to update all elements in the vector.
  std::transform(std::cbegin(v), std::cend(v), std::begin(v),
                 [](int v) { return 2 * v; });

  // Print elements; resulted: 2 4 6 .
  std::copy(std::cbegin(v), std::cend(v),
            std::ostream_iterator<int>(std::cout, " "));

  return 0;
}