//
// simple recursive function to compute non-negative integer powers,
// plus test program
//
#include <iostream>
#include <cstdlib>		// has EXIT_SUCCESS
#include <cassert>		// has assert()
using namespace std;

// function to compute integer power
// pre:  e >= 0
// post:  returns e-th power of b
double power(double b, int e) {
  assert(e >= 0);
  if (e == 0)
    return 1;
  else if (e % 2 == 0)
    return power(b*b, e >> 1);
  else
    return b * power(b*b, e >> 1);
}

// 
// test program
//
int main(void) {

  double b;
  int e;

  cout << "Enter b (floating-point) and e (non-negative integer):\n";
  cin >> b >> e;
  cout << b << " to the " << e << "-th power is " << power(b, e) << endl;

  return EXIT_SUCCESS;
}