CPP Functions call itself

Function can call itself?

• When function can call itself, it is called recursion.
• You must keep in mind that when a function calls itself, a new copy of that function is running.
  Recursion example (power of a number):

  Source code

  Result

  #include <iostream> using namespace std; typedef unsigned short USHORT; typedef unsigned long ULONG; ULONG GetPower(USHORT n, USHORT power); int main() { USHORT number, power; ULONG answer; cout << "Enter a number: "; cin >> number; cout << "To what power? "; cin >> power; answer = GetPower(number,power); return 0; } // The GetPower function returns base // raised to the power ULONG GetPower(USHORT base, USHORT power) { ULONG value=base; if (power == 1) { cout << base << " in power of " << power ; cout << " is: " << value << "\n"; return value; } else { value= value * GetPower(base,power-1); cout << base << " in power of " << power ; cout << " is: " << value << "\n"; return (value); } }

  Enter a number: 5 To what power? 8 5 in power of 1 is: 5 5 in power of 2 is: 25 5 in power of 3 is: 125 5 in power of 4 is: 625 5 in power of 5 is: 3125 5 in power of 6 is: 15625 5 in power of 7 is: 78125 5 in power of 8 is: 390625

  You could use Recursion with care, as it could be very memory consuming.

  You can download this example here (needed tools can be found in the right menu on this page).