init FFFF

//-std=c99 -Wall -Wextra -Wpedantic -Wshadow

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

int main()
{

    uint32_t a = 0xFFFFFFFF;

    printf("a: %X\n", a);

    uint32_t b = (uint32_t) -1;

    printf("b: %X\n", b);

    uint32_t c = ~(uint32_t)0;

    printf("c: %X\n", c);

    uint64_t d = 0xFFFFFFFFFFFFFFFF;

    printf("d: %lX\n", d);

    uint64_t e = (uint64_t) -1;

    printf("e: %lX\n", e);

    uint64_t f = ~(uint64_t)0;

    printf("f: %lX\n", f);

    return 0;
}

/*
output:

a: FFFFFFFF
b: FFFFFFFF
c: FFFFFFFF
d: FFFFFFFFFFFFFFFF
e: FFFFFFFFFFFFFFFF
f: FFFFFFFFFFFFFFFF

*/