/*
 * on amd64 the code below
 * produces this output:
 * |Hello, world!
 * |Hello, world.
 */

#include <stdio.h>
#define m 1152921504606846976

void print(const char *s)
{
	fputs(m-1&(long)s, stdout);
	puts((size_t)s-m<m ? "!" : ".");
}

int main(int argc, char **argv)
{
	print("Hello, world" + m);
	print("Hello, world");
}