c++简介:
c++是面向对象的编程,特点可以概括为4个字:封装、抽象、继承、多态,把对象的属性和方法集合成一个独立的系统单位,尽可能隐藏对象的内部细节,对具体的问题进行概括的过程,子类对象拥有与基类相同的全部属性和方法,子类继承基类的属性和行为后,可以具有不同的数据类型和表现行为等特性。
常用代码、函数介绍:
cout:console out(控制台输出)
数据类型:数组、指针、结构:
一个数组可以把很多同类型的数值存在一个变量名下
e.g
#include <iostream> #define ITEM 10 #define input_add() int main() { //const unsigned short ITEM = 10; int num[ITEM]; std::cout << "please input" << ITEM << "int number!\n\n"; input_add(); return 0; } void input_add() { for(int i=0; i<ITEM; i++) { std::cout << "please input" << i+1 << "number\n"; std::cin >> num[i] while(!(std::cin >> num[i])) { std::cin.clear(); std::cin.ignore(100,'\n'); std::cout << "please input again! \n"; } } int total = 0; for(int j=0; j<ITEM; j++) { total += num[j] } std::cout << "total is " << total << "\n" std::cout << "mean is " << (float)total/ITEM; std::cout << "\n" }
int a = 345; char b = 'C'; int *aPointer = &a; char *bPointer = &b;
std::cout << *aPointer; //*aPointer = 123; 会改变a的值
int myArray[3]={1,2,3};
对象的基础--结构:
struct name { type varName1; type varName2; ...... }
e.g
结构和指针:
Student Children = {"xiaoming", "00001", 'M'} Student *pChildren = &Children; (*pChildren).name = "lilei"; (*pChildren).id = "0002";
union mima { unsigned long birthday; .... };
//定义一个汽车的类 #include <iostream> #include <windows.h> #define FULL_GAS 85 class Car { public: std::string color; std::string engine; float gas_tank; unsigned int Wheel; void setColor(std::string col); void setEngine(std::string eng); void setWheel(unsigned int whe); void fill_tank(float liter); void running(void); void warning(void); } void Car::fill_Tank(float liter) { gas_tank +=liter; } void Car::running(void) { } void Car::warning(void) { } void Car::setColor(std::string col) { } void Car::setEngine(std::string eng) { } void Car::setWheel(unsigned int whe) { } int main() { char i; Car mycar; mycar.setColor("blue"); mycar.setEngine("v8"); mycar.setWheel(4); mycar.gas_tank = FULL_GAS; while(mycar.running()) { if(mycar.running() < 10 ) { mycar.warning(); std::cout << "input?(y/n)\n"; std::cin >> i; if( 'y' == i || 'Y' == i ) { mycar.fill_tank(FULL_GAS); } } } return 0; }
文章来源: c++学习笔记(一)---数据类型和对象