just playing c

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

int main (int argc, char **argv)
{

    unsigned long l1 = (~0ul & 0xffffffff) >> (32 - 32);
    unsigned long l2 = (~0ul & 0xffffffff) >> (32 - 16);

    printf("l1: 0x%lX\n", l1);
    printf("l2: 0x%lX\n", l2);

    unsigned long l3 = ~0ul >> (64 - 64);

    printf("l3: 0x%lX\n", l3);

    unsigned long l4 = ~0ul >> (64 - 16);

    printf("l4: 0x%lX\n", l4);

    unsigned long l5 = ~0ul >> (64 - 20);

    printf("l5: 0x%lX\n", l5);

    return 0;
}

/*
output:

l1: 0xFFFFFFFF
l2: 0xFFFF
l3: 0xFFFFFFFFFFFFFFFF
l4: 0xFFFF
l5: 0xFFFFF

*/