x^n

#include <cstdio>

//x^n evaluation
int main() {
  double x = -10;
  int n = 10;


  int bc_n = n; //Save n for correct output;
  bool invert = (n < 0);
  if (invert) {
    n = -n;
  }

  double res = 1;
  double pw = x;


  while (n) {
    if (n & 1) res *= pw;
    pw *= pw;
    n >>= 1;
  }

  if (invert) {
    res = 1 / res;
    n = -n;
  }

  printf("%lf^%d = %lf\n", x, bc_n, res);

  return 0;
}