程序代码如下：


#include<iostream>
using namespace std;
class Cargo
{
private:
    float weight;
    static int Totalnum;
    static float Totalweight;
public:
    Cargo(float w=0);
    ~Cargo();
    static void print();
};
Cargo::Cargo(float w)
{
    weight = w;
    Totalweight += weight;
    Totalnum++;
}
Cargo::~Cargo()
{
    Totalweight -= weight;
    Totalnum--;
}
void Cargo::print()
{
    cout << "Total weight=" << Totalweight << endl << "Total num=" << Totalnum << endl;
}
int main()
{
    float weight;
    cout << "input weight1:";
    cin >> weight;
    Cargo c1(weight);
    cout << "input weight2:";
    cin >> weight;
    Cargo c2(weight);
    Cargo::print();
    return 0;
}



请问这个是什么错误？

提示说得很清楚呀，你还是定义一下吧
int Cargo::Totalnum = 0;
另一个也一样

明白了，多谢