#include//input output stream 输入输出流 using namespace std;//使用std 的名称空间,cin cout在其中,也可在cincout 前加std:: #include int main() { cout << "hello world" << endl; //end of line换行 int a = 10; cout << "a=" << a << endl; cout << a << endl; cout << "a所占内存空间为:" << sizeof(a) << endl; cout << "int所占内存空间为:" << sizeof(int) << endl; cout << "int*所占内存空间为:" << sizeof(int*) << endl; //转义字符 n--换行符 \--反斜杠 t--水平制表符 cout << "\" << endl; cout << "abcdthahaha" << endl; //具有对齐效果 cout << "abthahaha" << endl; //字符串风格 string类 char arr[] = "abcde"; string brr = "abcde"; cout << arr << endl; cout << brr << endl; cout << arr + brr << endl;//可以相加 //bool数据类型(1字节);true--真(非0) false--假(0) bool flag1 = true; bool flag2 = false; cout << flag1 << endl; cout << flag2 << endl; cout << sizeof(bool) << endl; //地址 int crr[5] = { 1,2,3,4,5 }; cout << crr << endl; cout << &crr[0] << endl; cout << (int)crr << endl; //new 在堆区开辟数据 int *p = new int(10); cout << *p << endl; delete p; p = NULL; int* pa = new int[10]; for (int i = 0; i < 10; i++) pa[i] = i + 100; for (int i = 0; i < 10; i++) cout << pa[i] << endl; delete[] pa; //引用:给变量起别名 数据类型 &别名=原名 int i = 10; int& j = i; //引用必须初始化,且初始化后不可更改 cout << j << endl; j = 11; cout << i << endl; //int &a=10;--error //const int &a;--ok--会自动生成临时变量int tmp=10;const int &a=tmp; //C++的数据输入 string w = "adsdf"; bool h = false; cout << "nn给布尔类型h赋值" << endl; cin >> h; cout << h << endl; //只要是非0值都代表真 system("pause"); }



