krx20700.c

来自「answer of the c programming language sec」· C语言 代码 · 共 21 行

unsigned invert(unsigned x, int p, int n)
{
    return x ^ (~(~0U << n) << p);
}

/* main driver added, in a hurry while tired, by RJH. Better test driver suggestions are welcomed! */

#include <stdio.h>

int main(void)
{
  unsigned x;
  int p, n;

  for(x = 0; x < 700; x += 49)
    for(n = 1; n < 8; n++)
      for(p = 1; p < 8; p++)
        printf("%u, %d, %d: %u\n", x, n, p, invert(x, n, p));
  return 0;
}