是我的算法问题吗？

vbs就是慢的 算法没啥问题

开几个internet explorer组件 用js“多线程计算”
手动狗头

你看看这个怎么样
function getprimefrom2(num)
dim a()
redim a(-1)
dim bool_
bool_=true
for i=2 to num
bool_=true
for j=0 to ubound(a)
if i mod a(j)=0 then
bool_=false
exit for
end if
next
if bool_ then
redim preserve a(ubound(a)+1)
a(ubound(a))=i
end if
next
msgbox ubound(a)+1
end function
getprimefrom2(10000)
还能优化不少其实

这样似乎更快一点
function getprimefrom2(num)
dim a(),b
b=1
redim a(b)
a(0)=2
a(1)=3
dim bool_
bool_=true
for k=6 to num step 6
if k mod 10000 <=6 then wscript.stdout.writeline(k)
for i=k-1 to k+1 step 2
bool_=true
for j=0 to ubound(a)
if i mod a(j)=0 then
bool_=false
exit for
end if
next
if bool_ then
b=b+1
redim preserve a(b)
a(b)=i
end if
next
next
msgbox b+1
end function
getprimefrom2(1000000)
wscript.stdin.readline

越来越慢是因为到后面要找的数组越来越长

这也算埃氏吧

function getprimefrom2(num)
set a=CreateObject("System.Collections.ArrayList")
a.add(2)
a.add(3)
dim bool_
bool_=true
for k=6 to num step 6
for i=k-1 to k+1 step 2
bool_=true
for j=0 to a.count-1
if i mod a.item(j)=0 then
bool_=false
exit for
end if
next
if bool_ then
a.add(i)
end if
next
next
msgbox a.count
end function
getprimefrom2(10000)
换了个数组