1. Language enhancements and additions Learning & Development Team http://academy.telerik.com Telerik Software Academy

2. 1. Runtime performance enhancements  Rvalue references and move constructors  Generalized constant expressions 2. Usability enhancements  Initializer lists  Type inference  Range based for loop  Lambda functions and expressions  Null pointer constant  Right angle bracket 2

3. 3. Standard Template Library  Tuple types  Hash tables  Extensible random number facility 4. Algorithms  Non-modifying / modifying sequence  Sorting, minmax, heaps

4. T&& and move constructor

5.  Lvalues (references)  Lie on the left side of assignments  Identified by T&  Rvalues (temporaries)  Lie on the right side of assignments  Identified by T&&  Make move semantics possible

6.  Moves the contents of str to str_moved  Fast and doesn't allocate another 1GB of memory  str will be an empty string after the assignment  Move constructors on STL containers:  Given a really big string ( 1GB ) 6 string str(1<<30); string str_moved = move(str); string str_copied = str;  Copies the big string  Slow and allocates another 1GB of memory

7.  Move semantics on STL containers: 7 string append_char(string str, char ch) { str += ch; return move(str); return move(str);} // Really big string (1GB) string str(1<<30); string str2 = append_char(move(str), '5');

8. constexpr keyword

9.  Allows constant expressions to be functions  Restrictions (more relaxed in C++ 14 )  Function must be non-void  Variables can not be declared  Types can not be defined  Only one statement allowed (return value) // Array size must be a compile time constant int A[5+10*23]; // constexpr keyword guarantees that // a function is a compile time constant constexpr int square(int x) { return x*x; return x*x;} int B[square(10)];

10. Initializing arrays, containers and other structures

11.  Initializer list ( {value, value, … } )  Type initializer_list can be cast to:  STL containers  Pairs and tuples  Custom structures  Can be nested  " = " can be omitted ( uniform initialization )

12. Examples: 12 int array[] = {1, 3, 2, 5, 7}; // from C vector v = {1, 3, 2, 5, 7}; v = {1, 2, 3}; set s = {1, 3, 2, 5, 7}; pair SumAndDif(int a, int b) { return {a+b, a-b}; return {a+b, a-b};} map Map = { {"banana", 3}, {"banana", 3}, {"apple", 7}, {"apple", 7}, {"cherry", -5} {"cherry", -5}};

13. Examples: 13 struct rgb { double red; double red; double green; double green; double blue; double blue;} // Can be used on custom structures rgb color = {1.0, 0.5, 0.0}; // Can be nested vector colors = { {0, 0, 0}, {0, 0, 0}, {1, 1, 1}, {1, 1, 1}, {0.5, 0, 1}, {0.5, 0, 1}, {0.2, 0.8, 0.4} {0.2, 0.8, 0.4}};

14. auto, decltype

15.  Auto ( auto variable = value )  Deduces type for variable from value  Does not deduce const types  Does not deduce reference (&) types  Decltype ( declype(expression) )  This is the type of the expression  Can deduce const types  Can deduce reference types 15

16.  Examples: int a0; // int (apparently) auto a1 = a0; // int auto a2 = 7; // int auto a3 = 7-a0*(13+a1); // int auto a4 = 2ll; // long long const char c0 = 'x'; // const char (apparently) auto c1 = c0; // char (non-const) const auto c2 = c0; // const char char &r0 = c1; // char& (apparently) auto r1 = r0; // char (non-reference) auto &r2 = r0; // char& int *p0 = &a0; // int* (apparently) auto p1 = p0; // int*

17.  Useful when working with iterators map Map; for (map ::iterator it = Map.begin(); it != Map.end(); ++it) { it != Map.end(); ++it) { cout first " second first " second <<'\n';} // becomes for (auto it = Map.begin(); it != Map.end(); ++it) { cout first " second first " second <<'\n';}

18.  Examples: int a; // decltype(a) is int // decltype((a)) is int&, because (a) is an lvalue // decltype(0) is int, because 0 is an rvalue const vector v(1); // decltype(v[0]) is const int&

19. Iterating over arrays and containers

20.  Iterating over range of elements  C style arrays  STL containers  Initializer lists  Any type with defined begin() and end() functions 20

21.  Accessing all elements  Modifying all elements int A[10] = {1, 5, 9, 2, 4, 0, 2, 2, 7, 9}; for(int x:A) { cout<<x<<'\n'; cout<<x<<'\n';} int A[10] = {1, 5, 9, 2, 4, 0, 2, 2, 7, 9}; for(int x:A) { // Copies each element in x x *= 2; // A is not modified x *= 2; // A is not modified} for(int &x:A) { // Using reference x *= 2; // A is modified x *= 2; // A is modified}

22.  Can be used on STL containers  Combining with auto vector = {"Pencil", "Knife", "Ball"}; for(string &x:A) { reverse(x); reverse(x);} map Map; for (pair &x:Map) { cout " "<<x.second<<'\n';} // becomes for (auto &x:Map) { cout " "<<x.second<<'\n';}

23. Definition and usage

24.  [](int x,int y) { return x+y; }  Return type is decltype(x+y)  Variable capture  []  [variable]  [&variable]  [&]  [=] 24

25. Examples: vector v; sort(v.begin(), v.end(), [](int x, int y) { return abs(x) < abs(y); return abs(x) < abs(y);}); int n; cin >> n; sort(v.begin(), v.end(), [&n](int x, int y) { return x%n < y%n; return x%n < y%n;});

26. nullptr constant

27.  nullptr – Constant of type nullptr_t  Can be cast to any pointer type  Can not be cast to integer types  Can be cast to bool ( it's false ) 27 void f(int); void f(char*); // NULL is defined as 0 which is int f(NULL); // calls f(int) – Wrong f(nullptr); // calls f(char*) – Correct

28. C++ 03 and before vector > items C++ 11  Nested template declarations  Before C++ 11 " >> " is always defined as right shift

29. C++ 03 and before vector > items; C++ 11  Nested template declarations  Before C++ 11 " >> " is always defined as right shift Space required before C++ 11 Space not required in C++ 11

30. Creating and using tuples

31.  Tuple ( #include )  Creating tuples  tuple t;  tuple t(value1, value2, …);  tuple t{value1, value2, …};  make_tuple(value1, value2, …);  Accessing tuple elements ( get )  Unpacking tuples ( tie, ignore )  Concatenating tuples ( tuple_cat ) 31

32. Examples: tuple tup(42, "hamster", true); cout (tup); // cout's 42 cin >> get (tmp); // cin's a string get (tmp) = false; // Unpacking the tuple in // num and str, ignoring the Boolean // tie creates a tuple of references int num; string str; tie(num, str, ignore) = tup;

33. Examples: tuple tup(42, "hamster", true); int n = 17; auto tup2 = tuple_cat(tup, make_tuple(3.5), tup, tie(n)); // tup2 is of type tuple<int, string, bool, double, int, string, double, int&> int, string, double, int&> n = 19; // last element in tup2 is reference to n // (42, "hamster", true, 3.5, 42, "hamster", 19)

34. Unordered_(multi)set, unordered_(multi)map

35.  Unordered_(multi)set, unordered_(multi)map  Same as (multi)set and (multi)map  but unordered  Key must have defined Hash function instead of Compare  Extracting elements one by one:  Yields the elements in some order

36.  Unordered_(multi)sets ( #include )  unordered_set, Alloc = new>  Unordered_(multi)maps ( #include )  unordered_map, Alloc = new>  Constant average times for operations 36

37. Random number generators and distributions

38.  Non-deterministic numbers  random_device  Random number engines  Predefined generators  Engine adaptors  Distributions  Uniform  Normal  Others 38

39.  linear_congruential_engine  minstd_rand  minstd_rand 0  mersenne_twister_engine  mt 19937  mt 19937_64  subtract_with_carry_engine  ranlux 24 _base  ranlux 48 _base

40.  discard_block_engine  ranlux 24  ranlux 48  independent_bits_engine  shuffle_order_engine  knuth_b

41. Examples: #include #include using namespace std; int main() { random_device rd; random_device rd; // get a random number // get a random number cout << rd() << '\n'; cout << rd() << '\n'; mt19937 gen(seed); // seed can be rd() mt19937 gen(seed); // seed can be rd() // get a pseudo-random number // get a pseudo-random number cout << gen() << '\n'; cout << gen() << '\n';}

42.  Uniform distributions  uniform_int_distribution  uniform_real_distribution  generate_canonical  Normal distributions  normal_distribution  Others  Others

43. Examples: mt19937 gen{random_device{}()}; // generator uniform_int_distribution dice(1, 6); // Gives number from 1 to 6 with equal probability dice(gen); uniform_real_distribution reals(0.0, 10.0); // Evenly distributed real numbers from 0 to 10 reals(gen); normal_distribution gauss(42, 5); // Numbers close to 42 will be most probable // 5 is standard deviation gauss(gen);

44. New algorithms in New algorithms in

45.  Non-modifying sequence operations  all_of(first, last, predicate)  any_of(first, last, predicate)  none_of(first, last, predicate)  Modifying sequence operations  move(first, last, d_first)  move_backwards(first, last, d_last)  shuffle(begin, end, generator)  Uses the new random number functionality  Replaces random_shuffle 45

46.  Sorting operations  is_sorted(begin, end)  is_sorted_until(begin, end)  Min/max operations  minmax(a, b)  minmax_element(begin, end)  is_permutation(first1, last1, first2, last2)  Heap operations  is_heap(begin, end)  is_heap_until(begin, end) 46

47. форум програмиране, форум уеб дизайн курсове и уроци по програмиране, уеб дизайн – безплатно програмиране за деца – безплатни курсове и уроци безплатен SEO курс - оптимизация за търсачки уроци по уеб дизайн, HTML, CSS, JavaScript, Photoshop уроци по програмиране и уеб дизайн за ученици ASP.NET MVC курс – HTML, SQL, C#,.NET, ASP.NET MVC безплатен курс "Разработка на софтуер в cloud среда" BG Coder - онлайн състезателна система - online judge курсове и уроци по програмиране, книги – безплатно от Наков безплатен курс "Качествен програмен код" алго академия – състезателно програмиране, състезания ASP.NET курс - уеб програмиране, бази данни, C#,.NET, ASP.NET курсове и уроци по програмиране – Телерик академия курс мобилни приложения с iPhone, Android, WP7, PhoneGap free C# book, безплатна книга C#, книга Java, книга C# Николай Костов - блог за програмиране

48.  C# Programming @ Telerik Academy  csharpfundamentals.telerik.com csharpfundamentals.telerik.com  Telerik Software Academy  academy.telerik.com academy.telerik.com  Telerik Academy @ Facebook  facebook.com/TelerikAcademy facebook.com/TelerikAcademy  Telerik Software Academy Forums  forums.academy.telerik.com forums.academy.telerik.com