##include <iostream.h>    //包含iostream.h頭文件
void main()
{
    //輸出字符常量、變量和字符串
    char c1='A';
    cout<<'W';
    cout<<c1<<endl;
    cout<<"This is a test."<<endl;
    cout<<"------------------"<<endl;

    //輸出整型常量、變量和表達式
    int n=100;
    cout<<10;
    cout<<n;
    cout<<2*n<<endl;   //輸出整型表達式
    cout<<"------------------"<<endl;

    //輸出浮點型常量、變量和表達式
    double pi=3.1415926,r=10.0,s=pi*r*r;
    cout<<pi<<endl;
    cout<<r;
    cout<<s;
    cout<<2*r*pi<<endl;      //輸出浮點型表達式
    cout<<"------------------"<<endl;
    
    //一個cout可以輸出多項數(shù)據(jù)
    cout<<'W'<<" "<<c1<<endl;
    cout<<"This is a test."<<endl;
    cout<<"pi="<<pi<<" r="<<r<<" s="<<s<<endl;
}