Computing Power of 2

/* power2.c -- Print out powers of 2: 1, 2, 4, 8, .. up to 2^N
 */

#include <stdio.h>
#define N 16

int main(void) {
  int n;           /* The current exponent */
  int val = 1;     /* The current power of 2  */

  printf("\t  n  \t    2^n\n");
  printf("\t================\n");
  for (n=0; n<=N; n++) {
    printf("\t%3d \t %6d\n", n, val); 
    val = 2*val;
  }
  return 0;
}

/* It prints out :

   n       2^n
 ================
   0        1
   1        2
   2        4
   3        8
   4       16
   5       32
   6       64
   7      128
   8      256
   9      512
  10     1024
  11     2048
  12     4096
  13     8192
  14    16384
  15    32768
  16    65536

*/