#include<iostream>
using namespace std;

void get_numbers(int& input1,int& input2);
void swap_values(int& variable1,int&  variable2);
void show_results(int out1,int out2);

int main()
{
  int first_num,second_num;

  get_numbers(first_num,second_num);
  //cout<<first_num;
  swap_values(second_num,first_num);
  //cout<<first_num;
  show_results(first_num,second_num);

  return 0;
}

void get_numbers(int& input1,int& input2)
{
    cout<<"Enter your two numbers:\n";
    cin>>input1
        >>input2;
    cout<<endl;
}

void swap_values(int& variable1,int& variable2)
{
    int tem;
    tem=variable1;
    variable1=variable2;
    variable2=tem;
}

void show_results(int output1,int output2)
{  

    cout << "firstnum is :"<<output1<<endl;
    cout <<"secondnum is:"<<output2<<endl;
}


当在把void swap_values(int& variable1,int& variable2)改为传值调用的时候，怎么交换功能就不能实现了？
本人新手，谢谢了！

没啊，我试了多变，还是没交换值呢？不是引用调用，引用调用可以，值就不可以了，，郁闷.\

#include<iostream>
using namespace std;

void get_numbers(int& input1,int& input2);
void swap_values(int variable1,int  variable2);
void show_results(int out1,int out2);

int main()
{
  int first_num,second_num;

  get_numbers(first_num,second_num);
  //cout<<first_num;
  swap_values(first_num,second_num);
  //cout<<first_num;
  show_results(first_num,second_num);

  return 0;
}

void get_numbers(int& input1,int& input2)
{
    cout<<"Enter your two numbers:\n";
    cin>>input1
        >>input2;
    cout<<endl;
}

void swap_values(int variable1,int variable2)
{
    int tem;
    tem=variable1;
    variable1=variable2;
    variable2=tem;
    cout<<variable2;
}

void show_results(int output1,int output2)
{  

    cout << "firstnum is :"<<output1<<endl;
    cout <<"secondnum is:"<<output2<<endl;
}

再看下，谢谢了

太谢谢了。。有点懂了……我再练习个…………

DigitalTime::DigitalTime(int the_hour,int the_minute)
{
    if(the_hours<0||the_minute>59||the_hour>23||the_minute<0)
    {
        cout<<"Illgal argument to DigitalTime constructor.\n"'
            exit(1);
    }
    else
    {
        hour=the_hour;
        minute=the_minute;
    }

}

像这样的定义构造函数，给私有变量hour和minute初始化，算不算是传值调用呢?要是的话，在调用函数外部，私有变量岂不是没法初始化了？