急啊,来救救我。。。。。。
这个文件的显示内容,我有点不理解,请高手与我讲解:
#include <iostream>
using namespace std;
void f1(int);
int f2(int);
int main()
{
void(*p1)(int) = f1;
int(*p2)(int)=NULL;
cout << "p1=" << p1 << endl;
cout << "p2=" << p2 << endl;
p2 = f2;
p1(100);
cout << p2(100) << endl;
p1(p2(5));
cout << "p1=" << p1 << endl;
cout << "p2=" << p2 << endl;
}
void f1(int n){
cout << "n=" << n << endl;
}
int f2(int n){
return n*n;
}