skuny

@echo off
set /a a=0
for /f %%i in (1.txt) do (
set /a a=a+%%i
)
echo %a%
pauseCOPY

skuny

@echo off 
setlocal enabledelayedexpansion
set /a a=0
for /f %%i in (1.txt) do (
set /a a+=1
if !a! gtr 1 echo !b! %%i
set b=%%i
)
endlocal
pauseCOPY

skuny

::不是比较上下两行，而是比较全部内容
@echo off 
setlocal enabledelayedexpansion
for /f %%i in (1.txt) do (
set /a b=0
for /f %%j in (1.txt) do (
if %%i == %%j (set /a b+=1)
)
if !b! gtr 1 echo %%i 重复!b!次
if !b! == 1 echo 单一的数字为：%%i
)
endlocal
pauseCOPY