3. 给出程序的输出结果，如有错误，请改正
#include <iostream>
#include<string>
using namespace std;
void print(const string &s1)
{
cout << "call for void print(const string &s1)" << endl;
cout << s1;
}
void print(string &s1)
{
cout << "call for void print(string &s1)" << endl;
cout << s1;
}
void print(string s1)
{
cout << "call for void print(string s1)" << endl;
cout << s1;
}
int main()
{
print("world");
return 0;
}
为什么const string &s1会和string s1一样？导致print过载
4. 给出程序的输出结果，如有错误，请改正
#include <iostream>
using namespace std;
float temp;
float area1(float r)
{
temp = r*r*3;
return temp;
}
float& area2(float r)
{
temp = r*r*3;
return temp;
}
int main()
{
float a1 = area1(5.0);
float& a2 = area1(5.0);
float& a3 = area2(5.0);
float a4 = area1(4) = 10;
float a5 = area2(4) = 20;
cout << a1 << endl;
cout << a2 << endl;
cout << a3 << endl;
cout << a4 << endl;
cout << a5 << endl;
return 0;
}

dd

dd