What is the fastest way to change a key of an element inside std::map

by

In C++17, the new map::extract function lets you change the key.
Example:

std::map<int, std::string> m{ {10, "potato"}, {1, "banana"} };
auto nodeHandler = m.extract(10);
nodeHandler.key() = 2;
m.insert(std::move(nodeHandler)); // { { 1, "banana" }, { 2, "potato" } }

More Related Contents:

  1. Is there any advantage of using map over unordered_map in case of trivial keys?
  2. Sorting std::map using value
  3. A std::map that keep track of the order of insertion?
  4. Why Can’t I store references in a `std::map` in C++?
  5. Hashtable in C++?
  6. map with incomplete value type
  7. Converting std::__cxx11::string to std::string
  8. How to overload std::swap()
  9. Why is my program slow when looping over exactly 8192 elements?
  10. What is the efficient way to count set bits at a position or lower?
  11. Virtual functions and performance – C++
  12. How can I measure CPU time and wall clock time on both Linux/Windows?
  13. Why are Python Programs often slower than the Equivalent Program Written in C or C++?
  14. Is there any guarantee of alignment of address return by C++’s new operation?
  15. Explain Morris inorder tree traversal without using stacks or recursion
  16. Getting an accurate execution time in C++ (micro seconds)
  17. Can the use of C++11’s ‘auto’ improve performance?
  18. A fast method to round a double to a 32-bit int explained
  19. Is there a 128 bit integer in C++?
  20. What is the Fastest Method for High Performance Sequential File I/O in C++?
  21. Fastest way to get a positive modulo in C/C++
  22. Do c++ templates make programs slow?
  23. Using std::map where V has no usable default constructor
  24. How can I make the map::find operation case insensitive?
  25. std::remove_const with const references
  26. Why can’t I use a “break” statement inside a ternary conditional statement in C++?
  27. Syntax for using std::greater when calling std::sort in C++
  28. Simple for() loop benchmark takes the same time with any loop bound
  29. New (std::nothrow) vs. New within a try/catch block
  30. C++ most efficient way to convert string to int (faster than atoi)

Leave a Comment