Display 14.3 CS311

//Program to demonstrate the recursive function power.
 #include <iostream>
 #include <cstdlib>
 using namespace std;
 int power(int x, int n);
 //Precondition: n > = 0.
 //Returns x to the power n.
 int main( )
 {
 for (int n = 0; n < 4; n++)
 cout << "3 to the power " << n
 << " is " << power(3, n) << endl;
 return 0;
 }
 //uses iostream and cstdlib:
int power(int x, int n)
 {
 if (n < 0)
 {
 cout << "Illegal argument to power.\n";
 exit(1);
 }
 if (n > 0)
 return ( power(x, n - 1) * x);
 else // n == 0
 return (1);
 }