中国DOS联盟

@echo off
setlocal enabledelayedexpansion
set a=3333333333
set b=9999999999
set a1=%a%0000000000
set/a jg=1%a1:~-9%-%a:~-9%
set a1=%a1:~0,-9%
set/a jg1=%a1:~-9%-1-%a:~0,-9%
set jg=%a1:~0,-9%%jg1%%jg%
for /l %%a in (0,1,19) do for /l %%b in (0,2,8) do (set tm=!jg:~%%a,1!
if !tm!==%%b set/a gs+=1)
echo %a%*%b%=%jg%
echo 共有%gs%个偶数  
pause 

@echo off
set a=5
set b=7
set C=2
set/a ji=a*b*c
set/a a1=ji/a
set/a b1=ji/b
set/a c1=ji/c
echo 这三个齿轮齿数最少应分别是%a1%,%b1%,%c1%齿!
pause