Computing powers 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

*/