China DOS Union

Originally posted by zw19750516 at 2008-7-14 10:39 AM:
The efficiency problem lies here: echo %input%|findstr >nul||set str=#%str:~1,-1%%#
In batch processing, try to use if for judgment as much as possible and use findstr less.

As mentioned earlier, this is for compatibility. What I'm most proud of is this sentence. And in fact, there is only a judgment of 2 letters here. No matter how long your CODE is, it's still 2 letters.

High efficiency and conciseness should be based on accuracy, right?

Compared with the code on floor 38, it runs much faster, and I admit it because it gives the answer almost instantly. But as the author said, it can't handle repeated letters.

My code on floor 57 needs to wait a bit. I want to improve it but due to the level problem, I can't improve it anymore.
Also, who can tell me what's wrong with the second paragraph of the code on floor 57? Thanks

[ Last edited by quya on 2008-7-14 at 11:20 AM ]

Originally posted by zw19750516 at 2008-7-14 08:38 AM:
Old-fashioned, the first consideration in code is efficiency, and the second is conciseness. Your solution has an efficiency issue, and ('echo %str%') can be modified to ("%str%").

After considering it, I have to face the problem of low efficiency, so the modification is as follows:

@echo off

set/p input=Please enter:

set string=0123456789abcdefghij



:pro1

set str=%input:~0,1%

set input=%input:~1%

call set string=%%string:%str%=#%%

if defined input goto pro1

set "str= "



:pro2

set str=%string:~-1%%str%%string:~0,1%

if %string:~0,1%==# set str=#%str:~1,-1%%#

if %string:~-1%==# set str=#%str:~1,-1%%#

set string=%string:~1,-1%

if not defined string goto end

goto pro2



:end

for /f "tokens=1,2 delims= " %%i in ("%str%") do echo %%j ^| %%i

pause

Now the speed is also very fast.

There is another problem to point out:
The if judgment statement had better add quotes. if "%string:~0,1%"=="#" or if "%string:~0,1%" equ "#"

Simplify further, making the idea clearer

@echo off

set/p input=Please enter:

set tab=012t456789abcd6fghi3



:pro1

call set tab=%%tab:%input:~0,1%=#%%

set input=%input:~1%

if defined input goto pro1



set "out= "

:pro2

set out=#%out%#

if not "%tab:~0,1%"=="#" if not "%tab:~-1%"=="#" set out=%tab:~-1%%out:~1,-1%%tab:~0,1%

set tab=%tab:~1,-1%

if defined tab goto pro2



for /f "tokens=1,2 delims= " %%i in ("%out%") do echo %%j ^| %%i

pause

Originally posted by qzwqzw at 2008-7-14 18:34:
Simplify it further, the idea is clearer

@echo off
set/p input=Please enter:
set tab=012t456789abcd6fghi3
:pro1
call set tab=%%tab:%input:~0,1%=#%%
set input=%input:~1%
if defined input ...

How to display the input changed to #
I'll make a change

@echo off

setlocal enabledelayedexpansion

set/p input=Please enter:

set tab=012t456789abcd6fghi3

set str=%tab%

set /a n-=1,m=0

:pro1

call set tab=%%tab:%input:~0,1%=#%%

set input=%input:~1%

if defined input goto pro1

:pro2

set/a n+=1,m-=1

if "!tab:~,1!"=="#" (set var1=!var1!!str:~%n%,1!&set var2=!str:~%m%,1!!var2!)else (

    if "!tab:~-1!"=="#" (set var1=!var1!!str:~%n%,1!&set var2=!str:~%m%,1!!var2!)else set var1=%var1%#&set var2=#%var2%)

set tab=%tab:~1,-1%

if defined tab goto pro2

echo %var1% ^| %var2%

pause