Demon

讲究效率的话，应该用Sieve of Eratosthenes（埃拉托斯特尼筛法），但是代码比较长

@ECHO OFF
SETLOCAL ENABLEDELAYEDEXPANSION

REM Author: Demon
REM Date: 2011/5/29
REM Website: http://demon.tw
REM Algorithm: Sieve of Eratosthenes
REM Reference: http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes

SET /A limit = 1000
SET /A prime = 2

CALL :Init
CALL :SievePrime
CALL :Display
PAUSE & GOTO :EOF

:Display
    FOR /L %%i IN (2, 1, %limit%) DO (
        SET t=!arr[%%i]!
        IF !t! NEQ 0 ECHO !t!
    )
GOTO :EOF

:Init
    FOR /L %%i IN (1, 1, %limit%) DO SET arr[%%i]=%%i
GOTO :EOF

:SievePrime
    SET /A pow = prime * prime
    IF %pow% LSS %limit% (
        SET /A n = prime * 2
        FOR /L %%i IN (!n!, %prime%, %limit%) DO SET arr[%%i]=0
        CALL :NextPrime
        GOTO :SievePrime
    )
GOTO :EOF

:NextPrime
    SET /A prime += 1
    FOR /L %%i IN (%prime%, 1, %limit%) DO (
        IF !arr[%%i]! NEQ 0 SET /A prime = %%i & GOTO :EOF
    )
GOTO :EOF
复制代码