#endif // foo.c int add(int x, int y) { return x+y; } // 1.1.cpp #include "foo.h" #include <iostream> #include int main() { [out = std::ref(std::cout << "Result from C code: " << add(1 equally or unequally with them. You can try to compile the following code using clang++: #include <iostream> #include void foo(char *); void foo(int); int main() { if (std::is_sameiostream> #define LEN 10 int len_foo() { int i = 2; return i; } constexpr int len_foo_constexpr() {

互相兼容情况 // foo.c int add(int x, int y) { return x+y; } // 1.1.cpp #include "foo.h" #include <iostream> #include int main() { [out = std::ref(std::cout << "Result from C code: " << add(1 nullptr 的类型 为 nullptr_t，能够隐式的转换为任何指针或成员指针的类型，也能和他们进行相等或者不等的比较。 你可以尝试使用 clang++ 编译下面的代码： #include <iostream> #include void foo(char *); void foo(int); int main() { if (std::is_sameiostream> #define LEN 10 int len_foo() { int i = 2; return i; } constexpr int len_foo_constexpr() {

1#include #include <iostream> #include int a[] = {0, 1, 2, 3, 4}; std::vector c = {0, 1, 2, 3, 4}; auto main() -> int { std::cout << "C style array: " << sizeof(a) / sizeof(a[0]) elements. Iterators Allocators Modifiers Oh My! 14The Basics 15Creating a std::vector #include <iostream> #include int main() { std::vector wa_years; // empty vector of years 0 [Done] exited with code=0 in 0.883 seconds 1 2 3 4 5 17Access data in a vector #include <iostream> #include int main() { std::vector co_years = {2019, 2020, 2021,

chrono::year_month_weekday_last • …11 Some examples: Simple Calendrical Types #include #include <iostream> using namespace std::chrono; int main() { year y{2021}; std::cout << y << "\n"; month 2021 Jan12 Some examples: Simple Calendrical Types (continued) #include #include <iostream> using namespace std::chrono; int main() { weekday wd{Thursday}; auto result = wd + days{4}; Mon Sun Sun Thu[4]13 Some examples: Compound Calendrical Types #include #include <iostream> using namespace std::chrono; int main() { year this_year{2021}; year last_year{2020};

Level Visualizing CompilationIncludes #include <iostream> int main() { std::cout << "Hello, world!" << std::endl; } 28Includes #include <iostream> int main() { std::cout << "Hello, world 1>::value; }; template <> struct Sum<0> { static const int value = 0; }; 33Templates 34 #include <iostream> template struct Sum { static const int value = N + Sum::value; }; template int value = 0; }; int main() { std::cout << Sum<5>::value << std::endl; }Templates #include <iostream> template struct Sum { static const int value = N + Sum::value; }; /* First instantiated

21.41. Can you get it? b) Delivery mechanism // Version identifier: 0.3.3 // <iostream> support: INCLUDED // List of included units: // amperes // bits // candelas // grams // https://commons.wikimedia.org/wiki/File:ADAF- 03-BRD_(14336910552).jpg Tired: Wired: double, float <iostream> 😰😱😵 int64_t, uint32_t, … const char[] 30.3Embedded friendliness By oomlout (Flickr), CC https://commons.wikimedia.org/wiki/File:ADAF- 03-BRD_(14336910552).jpg Tired: Wired: double, float <iostream> 😰😱😵 int64_t, uint32_t, … const char[] const auto &label = unit_label(Meters{} * Kilo{}

cpp"); } 43 That’s it. We only need a using (for namespace std) and a few standard includes (iostream, fstream, string, iterator)A word about beauty and elegance // ... string read_all_text(const class Program { static void Main() { Write(Square(2)); } } 119 #include #include <iostream> using namespace std; auto square(int n) { return pow(n,2); } int main() { cout << square(2); const #include class Integral { /* ... */ }; class Point { /* ... */ }; #include <iostream> int main() { Point pt{ 2,3 }; // cannot modify pt.x here std::cout << pt << '\n'; } 136The

Left 5C++20 STL Features Part 1 6Comparing Integers 7Usual Arithmetic Conversions #include <iostream> using namespace std; int main() { cout << boolalpha; short s = -1; unsigned int ui = 1729; This prints false 🙀 8Integer Comparison Functions • GH-621 implemented by Neargye #include <iostream> #include using namespace std; int main() { cout << boolalpha; short s = -1; while looping 🐞 16Uniform Container Erasure • GH-236 and GH-566 implemented by SuperWig #include <iostream> #include #include using namespace std; void print(const vector& v) {

Left6 C++20 STL Features Part 17 Comparing Integers8 Usual Arithmetic Conversions #include <iostream> using namespace std; int main() { cout << boolalpha; short s = -1; unsigned This prints false 🙀9 Integer Comparison Functions • GH-621 implemented by Neargye #include <iostream> #include using namespace std; int main() { cout << boolalpha; short s looping 🐞17 Uniform Container Erasure • GH-236 and GH-566 implemented by SuperWig #include <iostream> #include #include using namespace std; void print(const vector& v)

reserved. The Challenges of Mixed Type Storage #include #include #include <iostream> int main() { vv::vector vec; vec.reserve_bytes(64); vec.rese reserved. The Woes of operator [] #include #include #include #include <iostream> using combo_type = std::variant; int main() { std::vector P. All rights reserved. The Woes of operator [] #include #include #include <iostream> #include using vector = vv::vector; int main() {