Basic¶

"a"->string, 'a'->char

Value Range¶

有符号整数类型¶

类型	最小值	最大值	备注
`char`	-128	127	至少 8 位
`short`	-32,768	32,767	至少 16 位
`int`	-2,147,483,648	2,147,483,647	通常是 32 位
`long`	-2,147,483,648	2,147,483,647	至少 32 位，但可能更长
`long long`	-9,223,372,036,854,775,808	9,223,372,036,854,775,807	至少 64 位

无符号整数类型（非负数）¶

类型	最大值	备注
`unsigned char`	255	至少 8 位
`unsigned short`	65,535	至少 16 位
`unsigned int`	4,294,967,295	通常是 32 位
`unsigned long`	4,294,967,295	至少 32 位，但可能更长
`unsigned long long`	18,446,744,073,709,551,615	至少 64 位

Uniform Initialization¶

int a{5}; // 直接初始化
std::vector<int> v{1, 2, 3}; // 统一初始化

Auto Keyword for Type Inference¶

auto x = 42;  // int
auto y = 42.0;  // double

Range-based For Loops¶

for (const auto& elem : vec) {
    // Do something with elem
}

Lambda Expressions¶

auto add = [](int a, int b) -> int {
    return a + b;
};

Smart Pointers¶

std::unique_ptr<int> p1(new int(42));
std::shared_ptr<int> p2 = std::make_shared<int>(42);

Template Functions¶

template <typename T>
T getMax(T a, T b) {
    return (a > b) ? a : b;
}

Move Semantics¶

std::vector<int> vec1 = {1, 2, 3};
std::vector<int> vec2 = std::move(vec1);  // Moves data from vec1 to vec2

Structured Binding (C++17)¶

std::pair<int, std::string> p = {1, "one"};
auto [num, word] = p;

Variadic Templates¶

template<typename... Args>
void printAll(Args... args) {
    // Do something
}

Pattern Match¶

Switch¶

int value = /* some value */;
switch (value) {
    case 1:
        // do something
        break;
    case 2:
        // do something else
        break;
    default:
        // default case
        break;
}

unordered_map¶

unordered_map<string, function<int(int, int)>> operations = {
            {"+", [](int a, int b) { return a + b; }},
            {"-", [](int a, int b) { return a - b; }},
            {"*", [](int a, int b) { return a * b; }},
            {"/", [](int a, int b) { return a / b; }}
        };