fork download
copy 
  1. #include <iostream>
  2. #include <type_traits>
  3. #include <vector>
  4. #include <map>
  5. using namespace std;
  6.  
  7. template<typename T>
  8. auto sum(const T& t, size_t n)
  9. {
  10. 	std::remove_const_t<std::remove_reference_t<decltype(*begin(T{}))>> result{};
  11. 	size_t i = 0;
  12. 	for (auto&& x : t) 
  13. 	{
  14. 		if (i++ >= n) break;
  15. 		result += x;
  16. 	}
  17. 	return result;
  18. }
  19.  
  20. template<typename K, typename V>
  21. auto sum(const std::map<K, V>& t, size_t n)
  22. {
  23. 	V result{};
  24. 	size_t i = 0;
  25. 	for (auto&& x : t) 
  26. 	{
  27. 		if (i++ >= n) break;
  28. 		result += x.second;
  29. 	}
  30. 	return result;
  31. }
  32.  
  33. int main() {
  34. 	vector<int> ints = {1, 2, 3, 4};
  35. 	cout << sum(ints, 2) << "\n";
  36. 	vector<string> strings = {"ala", " ", "ma ", "kota" };
  37. 	cout << sum(strings, 3) << "\n";
  38.  
  39. 	map<string, int> pairs = {{"1", 1}, {"2", 2}};
  40. 	cout << sum(pairs, 2) << "\n";
  41. 	return 0;
  42. }
Success #stdin #stdout 0s 3276KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
3
ala ma 
3
https://ideone.com/G8yXX5
language:
C++14 (gcc 8.3)
created:
10 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!