list0504.cpp

teach yourself C++ in 21 days 第五版

// Listing 5.4 - demonstrates passing by value
#include <iostream>

using namespace std;   
void swap(int x, int y);
  
int main()
{
   int x = 5, y = 10;
  
   cout << "Main. Before swap, x: " << x << " y: " << y << endl;
   swap(x,y);
   cout << "Main. After swap, x: " << x << " y: " << y << endl;
   return 0;
}
  
void swap (int x, int y)
{
   int temp;
  
   cout << "Swap. Before swap, x: " << x << " y: " << y << endl;
  
   temp = x;
   x = y;
   y = temp;
  
   cout << "Swap. After swap, x: " << x << " y: " << y << endl;
}