修改代码

王鹿其

#include <iostream>
using namespace std;
#define  PI  3.1415926;
#define  AREA(r)  PI * r * r

int main()
{
        double radius, s;
        cout << "Enter the radius of a circle: ";
        cin >> radius;
        s = AREA(radius);
        cout << "radius=" << radius << "The area is " << s << "\n";
        s = AREA(radius + 1);
        cout << "radius=" << (radius + 1) << "The area is " << s << "\n";
        return 0;
}

isdkz

#include <iostream>
using namespace std;
#define PI 3.1415926
#define AREA(r) PI * r * r

int main()
{
    double radius, s;
    cout << "Enter the radius of a circle: ";
    cin >> radius;
    s = AREA(radius);
    cout << "radius=" << radius << "The area is " << s << "\n";
    s = AREA(radius + 1);
    cout << "radius=" << (radius + 1) << "The area is " << s << "\n";
    return 0;
}

修改后的代码去掉了PI的分号，并且在宏定义AREA(r)中去掉了分号。分号会导致宏展开时出现意外的错误。

Mike_python小

#include <iostream>using namespace std;#define PI 3.1415926#define AREA(r) PI * r * rint main(){    double radius, s;    cout << "Enter the radius of a circle: ";    cin >> radius;    s = AREA(radius);    cout << "radius=" << radius << " The area is " << s << "\n";  // 在输出中添加空格分隔符    s = AREA(radius + 1);    cout << "radius=" << (radius + 1) << " The area is " << s << "\n";  // 在输出中添加空格分隔符    return 0;}

在这段代码中，我帮您去掉了宏定义末尾多余的分号，并且修正了输出语句中的空格分隔符。现在定义的PI和AREA宏应该可以正确计算圆的面积了。如果有其他问题或需要进一步帮助，请随时提问。