遞迴調用——C++ Primer Plus

#include <iostream>void countdown(int n);int main(){countdown(4);return 0;}void countdown(int n){using namespace std;cout<<"Counting down ... "<<n<<endl;if(n>0){countdown(n-1);}cout<<n<<": Kaboom!\n";}

注意，每個遞迴調用都建立自己的一套變數，因此當程式到達第5次調用時，將有5個獨立的n變數，其中每個變數的值都不同。為驗證這一點，讀者可以修改程式清單，使之顯示n的地址和值：

void countdown(int n){using namespace std;cout<<"Counting down ... "<<n<<" n at "<<&n<<")"<<endl;if(n>0){countdown(n-1);}cout<<n<<": Kaboom!"<<"         (n at "<<&n<<")"<<endl;}

Counting down ... 4 n at 0012FF30)Counting down ... 3 n at 0012FED8)Counting down ... 2 n at 0012FE80)Counting down ... 1 n at 0012FE28)Counting down ... 0 n at 0012FDD0)0: Kaboom!         (n at 0012FDD0)1: Kaboom!         (n at 0012FE28)2: Kaboom!         (n at 0012FE80)3: Kaboom!         (n at 0012FED8)4: Kaboom!         (n at 0012FF30)