#include <stdio.h>

#define __STDC_FORMAT_MACROS
#include <inttypes.h>

int main(void) 
{
	int i;
	unsigned char input[8] = {0x01, 0x02, 0x03, 0x04, 0x5, 0x06, 0x07, 0x08 };
	uint64_t paquet = 0;
	for( i = 7; i >= 0; --i )
	{
		paquet <<= 8;
	    paquet |= (uint64_t)input[i];
	    printf("%d: %u: %" PRIu64 "\n", i, input[i], paquet);
	}
	
	printf("%" PRIu64 "\n", paquet);
	
	return 0;
}