标题: [出题]计算指定十六进制数的二进制表示中包含1的个数 [打印本页]
作者: HAT 时间: 2008-11-13 00:20 标题: [出题]计算指定十六进制数的二进制表示中包含1的个数
当n=A时，{1010}，包含数字1的个数为2；
当n=B时，{1011}，包含数字1的个数为3；
当n=C时，{1100}，包含数字1的个数为2；
当n=F时，{1111}，包含数字1的个数为4；
当n=3B9AC9FF时，{1...1}，包含数字1的个数为多少呢？
请给出速度最快的解。
作者: dikex 时间: 2008-11-13 02:21
3B9AC9FF时是21
嗯，貌似即使用batch能处理的最大整数0x7FFFFFFF也能在瞬间搞定，比它快也貌似没有意义了-_-
@echo off
set /a rd=0x7FFFFFFF
:loop
set /a "rd1=rd%%2"
set /a "rd=rd/2"
if %rd1% equ 1 set /a n+=1
if %rd% neq 0 goto :loop
echo %n%
pause
[ Last edited by dikex on 2008-11-13 at 02:22 ]set /a rd=0x7FFFFFFF
:loop
set /a "rd1=rd%%2"
set /a "rd=rd/2"
if %rd1% equ 1 set /a n+=1
if %rd% neq 0 goto :loop
echo %n%
pause
作者: dikex 时间: 2008-11-13 02:36
哈哈，有空无事计算100次，得出计算100次平均用时是2.625s，也就是计算1次之用0.02625s
机子配置不同可能有差距
@echo off
echo %time%
:aa
call :cc
set /a c+=1
if %c% lss 100 goto :aa
echo %time%
pause
:cc
set /a rd=0x7FFFFFFF
set n=0
:loop
set /a "rd1=rd%%2"
set /a "rd=rd/2"
if %rd1% equ 1 set /a n+=1
if %rd% neq 0 goto :loop
goto :EOF
echo %time%
:aa
call :cc
set /a c+=1
if %c% lss 100 goto :aa
echo %time%
pause
:cc
set /a rd=0x7FFFFFFF
set n=0
:loop
set /a "rd1=rd%%2"
set /a "rd=rd/2"
if %rd1% equ 1 set /a n+=1
if %rd% neq 0 goto :loop
goto :EOF
附件 1:ss.JPG (2008-11-13 02:36, 20.31 K, 下载附件所需积分 1点 )
作者: HAT 时间: 2008-11-13 10:45 标题: Re 2楼
这个方法在我的电脑上单次运行需要9毫秒左右
我有另外一个方案可以在1毫秒内给出结果
纯粹是为了好玩
呵呵
作者: dikex 时间: 2008-11-14 01:58
洗澡时想到的算法^_^
比那个稍快
@echo off
echo %time%
:aa
call :cc
set /a c+=1
if %c% lss 100 goto :aa
echo %time%
pause
:cc
set /a a=0x7FFFFFFF
set n=0
set b=0
:loop
set /a "b+=(a>>%n%)&1"
set /a n+=1
if %n% lss 31 goto :loop
rem echo %b%
goto :EOF
echo %time%
:aa
call :cc
set /a c+=1
if %c% lss 100 goto :aa
echo %time%
pause
:cc
set /a a=0x7FFFFFFF
set n=0
set b=0
:loop
set /a "b+=(a>>%n%)&1"
set /a n+=1
if %n% lss 31 goto :loop
rem echo %b%
goto :EOF
作者: everest79 时间: 2008-11-14 07:08
这样？
Set /P "str=INPUT:"
Set /A "str=(str&0x55555555)+(str>>1&0x55555555)"
Set /A "str=(str&0x33333333)+(str>>2&0x33333333)"
Set /A "str=(str&0x0F0F0F0F)+(str>>4&0x0F0F0F0F)"
Set /A "str=(str&0x00FF00FF)+(str>>8&0x00FF00FF)"
Set /A "str=(str&0x0000FFFF)+(str>>16&0x0000FFFF)"
echo %str%
pause
[ Last edited by everest79 on 2008-11-15 at 01:26 ]Set /A "str=(str&0x55555555)+(str>>1&0x55555555)"
Set /A "str=(str&0x33333333)+(str>>2&0x33333333)"
Set /A "str=(str&0x0F0F0F0F)+(str>>4&0x0F0F0F0F)"
Set /A "str=(str&0x00FF00FF)+(str>>8&0x00FF00FF)"
Set /A "str=(str&0x0000FFFF)+(str>>16&0x0000FFFF)"
echo %str%
pause
作者: HAT 时间: 2008-11-21 23:24
@echo off
set hex=3B9AC9FF
set bin=%bin:3=11%
set bin=%bin:5=11%
set bin=%bin:6=11%
set bin=%bin:7=111%
set bin=%bin:9=11%
set bin=%bin:A=11%
set bin=%bin:B=111%
set bin=%bin:C=11%
set bin=%bin:D=111%
set bin=%bin:E=111%
set bin=%bin:F=1111%
set numOne=%bin:0=%
set "length=31"
:loop
set "numOne=%numOne%#"
set /a length-=1
if "%numOne:~30,1%" neq "#" goto :loop
echo %length%
pause
[ Last edited by HAT on 2008-11-22 at 02:58 ]set hex=3B9AC9FF
set bin=%bin:3=11%
set bin=%bin:5=11%
set bin=%bin:6=11%
set bin=%bin:7=111%
set bin=%bin:9=11%
set bin=%bin:A=11%
set bin=%bin:B=111%
set bin=%bin:C=11%
set bin=%bin:D=111%
set bin=%bin:E=111%
set bin=%bin:F=1111%
set numOne=%bin:0=%
set "length=31"
:loop
set "numOne=%numOne%#"
set /a length-=1
if "%numOne:~30,1%" neq "#" goto :loop
echo %length%
pause
作者: terse 时间: 2008-11-22 02:48
这样可行否？
@echo off&setlocal enabledelayedexpansion
set 1=1&set 2=1&set 3=2&set 4=1&set 5=2&set 6=2&set 7=3&set 8=1
set 9=2&set a=2&set b=3&set c=2&set d=3&set e=3&set f=4
set hex=7FFFFFFF
:lp
if defined hex (
set/a n+=!%hex:~,1%!
set hex=%hex:~1%
goto lp
)
echo.%n%
pause
set 1=1&set 2=1&set 3=2&set 4=1&set 5=2&set 6=2&set 7=3&set 8=1
set 9=2&set a=2&set b=3&set c=2&set d=3&set e=3&set f=4
set hex=7FFFFFFF
:lp
if defined hex (
set/a n+=!%hex:~,1%!
set hex=%hex:~1%
goto lp
)
echo.%n%
pause
作者: netbenton 时间: 2009-2-26 00:06 标题: 我也来一个
@echo off
set /a num=0x12345678
:loop
set /a n=num%%2,num=num/2
set /a _%n%+=1
if %num% gtr 0 goto :loop
echo 有%_0%个0
echo 有%_1%个1
pause
[ Last edited by netbenton on 2009-2-27 at 07:18 ]