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mystery.c
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mystery.c
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#include<stdio.h>
unsigned mystery(unsigned a) {
unsigned c = (a & -a);
unsigned r = a+c;
return ((((r ^ a) >> 2) / c) | r);
}
#define BYTETOBINARYPATTERN "%d%d%d%d%d%d%d%d"
#define BYTETOBINARY(byte) \
(byte & 0x80 ? 1 : 0), \
(byte & 0x40 ? 1 : 0), \
(byte & 0x20 ? 1 : 0), \
(byte & 0x10 ? 1 : 0), \
(byte & 0x08 ? 1 : 0), \
(byte & 0x04 ? 1 : 0), \
(byte & 0x02 ? 1 : 0), \
(byte & 0x01 ? 1 : 0)
void main(void)
{
unsigned doom=7;
for (int i=0; i< 100; i++) {
printf ("%3d -> "BYTETOBINARYPATTERN"\n", doom, BYTETOBINARY(doom));
doom=mystery(doom);
}
}
/* john@dell-mini-2$ gcc -std=gnu99 mystery.c */
/* ~/hobby-code */
/* john@dell-mini-2$ ./a.out */
/* 7 -> 00000111 */
/* 11 -> 00001011 */
/* 13 -> 00001101 */
/* 14 -> 00001110 */
/* 19 -> 00010011 */
/* 21 -> 00010101 */
/* 22 -> 00010110 */
/* 25 -> 00011001 */
/* 26 -> 00011010 */
/* 28 -> 00011100 */