1樓：匿名使用者
private sub command1_click()dim a as integer, b as integerdim i as integer, j as integerdim k as integer
a = 6
b = 100
list1.clear
for i = a to b step 2for j = 2 to i / 2
if prime(j) and prime(i - j) thenk = k + 1
list1.additem cstr(k) & "： " & cstr(i) & "=" & cstr(j) & "+" & cstr(i - j) '修改這裡的**就行了
end if
next j
next i
label1.caption = "6～100之間有" & cstr(k) & "對素數和"
end sub
'判斷是否為素數
private function prime(n as integer) as boolean
dim i as integer
if n = 1 then
exit function
elseif n = 2 then
prime = true
exit function
elseif n mod 2 = 0 thenexit function
end if
for i = 3 to sqr(n) step 2if n mod i = 0 then exit functionnext i
prime = true
end function
2樓：
此題需要先編寫一個求素數的自定義函式，具體如下：
1.開啟vb，畫一個listbox控制元件，名稱list1,再畫一個label控制元件，名稱label1
2.畫一個command控制元件，名稱command1
3.雙擊command1，開啟**視窗，輸入如下**：
function pdsu(a as integer) as integer
dim b as integer: dim i as integer
if a <= 3 then
pdsu = 1
else
b = a \ 2
for i = 2 to b
if (a mod i) = 0 then
pdsu = 0: exit function
exit for
end if
next i
pdsu = 1
end if
end function
private sub command1_click()
dim m as integer
dim n as integer
dim i as integer
dim s as integer
s = 0
for i = 6 to 100 step 2
for m = 2 to i - 2
n = i - m
if (pdsu(m) = 1) and (pdsu(n) = 1) then
list1.additem str(i) & "=" & str(m) & "+" & str(n): s = s + 1
exit for
end if
next m
next i
label1.caption = "6-100間共有" & str(s) & "對素數和"
end sub
4.如果操作輸入無誤，即可以顯示正常結果，共有48對素數和
說明：解答此題，我用了約10分鐘，給我加分吧
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