[skribanto]

how would you iterate over every possible value of a unsigned int?

[mtklein]

Usually I use a do-while loop,

    unsigned char x = 0;
    do {
        printf("%d\n", x);
    } while (++x);

[NoZebra120vClip]

The unary complement operator should get you there:

  unsigned int x = 0;
  const unsigned int max = ~x;

  while (x <= max) {
     calc(x++);
  }

Or,

  #include <limits.h>

  const unsigned int max = UINT_MAX;

[mnaydin]

This is equivalent to

  while (1) {
    calc(x++);
  }

which is an infinite loop, since the expression x <= max is always true

[NoZebra120vClip]

Heh! Good catch! That is what I get for not testing. After UINT_MAX, x wraps around to 0.

[kstenerud]

Or if you only wanted to iterate halfway:

    unsigned int x = 0;

    while (x < ~x) {
        calc(x++);
    }

Or going down:

    unsigned int x = ~0;

    while (x > ~x) {
        calc(x--);
    }

[NoZebra120vClip]

By "halfway", did you mean "off by one"?

[kstenerud]

no