C ѧϰ±Ê¼Ç£º ÒÆÎ»²Ù×÷Á·Ï°¡£
#include <stdio.h>
unsigned int reverse_bits(unsigned int value)
{
unsigned int answer;
unsigned int i;
answer = 0;
for(i=1;i!=0;i<<=1){ //´ËÑ»·¿ÉÒÔºöÂÔ»úÆ÷µÄ²îÒì¡£64λºÍ32λ½Ô¿ÉÓã¬ÔöÇ¿´Ë´úÂëµÄ¿ÉÒÆÖ²ÐÔ
answer <<=1;
if(value & 1)
answer |= 1;
value >>=1;
}
return answer;
}
int main(void)
{
unsigned int get_answer=reverse_bits(13);
int i=31;
char t;
while(i)
{
t ='0'+ ((get_answer >> i) & 1);
printf("%c",t);
i--;
}
}
<<CºÍÖ¸Õë>> µÚ5ÕÂÁ·Ï°Ìâ¡£
Linux 2.6 kernelÖеÄset_bit²Ù×÷£º
ÐèÒª¿¼ÂÇ»úÆ÷ÊÇ32λ»¹ÊÇ64λµÄ¼ÆËã»ú¡£
static inline void set_bit(int nr, volatile unsigned long *addr)
{
int *a = (int *)addr;
int mask;
//unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
//local_irq_save_hw(flags);
*a |= mask;
//local_irq_restore_hw(flags);
}
Ïà¹ØÎĵµ£º
1 ±à³Ì»ù´¡
1.1 »ù±¾¸ÅÄî
1. µÄÀí½â£ºconst char*, char const*, char*constµÄÇø±ðÎÊÌ⼸ºõÊÇC++ÃæÊÔÖÐÿ´Î ¶¼»áÓеÄÌâÄ¿¡£ ÊÂʵÉÏÕâ¸ö¸ÅÄî˶¼ÓÐÖ»ÊÇÈýÖÖÉùÃ÷·½Ê½·Ç³£ÏàËÆºÜÈÝÒ׼ǻ졣 Bja ......
Õû¸ö²âÊÔ×ñÑÒÔϵÄÔ¼¶¨£º
u
¼Ù¶¨ÔÚËùÓеijÌÐòÖбØÐëµÄÍ·Îļþ¶¼ÒѾ±»ÕýÈ·°üº¬¡£
¿¼ÂÇÈçϵÄÊý¾ÝÀàÐÍ£º
u
char
Ϊ
1
¸ö×Ö½Ú
u
int
Ϊ
4
¸ö×Ö½Ú
u
......
×î½üÔÚ×ö³ÌÐòʱÐèҪʹÓÃÒ»¸öÒѾ±àºÃµÄC³ÌÐòÔ´Îļþ£¨ÓÐÍ·Îļþ£©£¬½«Í·Îļþ¼ÓÈëÒªµ÷ÓõÄÔ´ÎļþÖУ¬µ÷ÓÃÏàÓ¦Cº¯Êý£¬±àÒëʱ³öÏÖÈçÏ´íÎó£º
sss.c(3129) : fatal error C1010: unexpected end of file while looking for precompiled header directive
ÔÚÍøÉϲéÁËÏà¹Ø×ÊÁÏ£¬Ëµ²»ÄÜÔÚCÔ´ÎļþÖаüº¬"stdafx.h"Îļþ£¬
ÖªµÀÐèÒªÒ ......
ÒÔÏÂÊǼ¸¸ö¼¬ÊÖµÄ
C ÎÊÌâ, ºÜÄÑ×ö, ¿´¿´×Ô¼º»á×ö¼¸¸ö?
How do you write a program which produces its own source code as its output?
How can I find the day of the week given the date?
Why doesn’t C have nested functions?
What is the most efficient way to count the num ......
C++²»¶¨²ÎÊýµÄÓ÷¨ £¨CÀàËÆ£©
2009-11-19 15:41
/*
va_list vl; //¶¨ÒåÒ»¸öÖ¸Ïò²ÎÊýÁбíµÄ±äÁ¿(Ò»¸ö...Ö¸Õë)
va_start(vl,first_param); //°ÑÖ¸Ïò²ÎÊýÁбíµÄ±äÁ¿³õʼ»¯
va_arg(vl,mode); //»ñÈ¡ÏÂÒ»¸ö²ÎÊý,²ÎÊýÀàÐÍÓɵڶþ¸ö²ÎÊýÖ¸¶¨,µÚ¶þ¸ö²ÎÊýÓÃÓÚÔÚva_argÄÚ²¿½øÐÐ³ß´ç¼ÆËã,ÒÔ±ãÕÒµ½ÏÂÒ»¸ö²ÎÊý
va_end(vl); //½áÊø
......