imports system.math
public class eightqueen
dim topnum as int16 = 7
dim printb as boolean
dim j2 as int16 = 0
dim eightqueenplace2((topnum * 2) * (topnum * 2), topnum, topnum) as int16
private sub button1_click(byval sender as system.object, byval e as system.eventargs) handles button1.click
dim eightqueenplace1(topnum, topnum) as int16
for i = 0 to topnum
for j = 0 to topnum
eightqueenplace1(i, j) = 1 '初始化
next
next
bu(eightqueenplace1, 0, 0, 0)
textbox1.text = textbox1.text + chr(13) + chr(10) + j2.tostring + "end" '輸出總種數和和結束標誌
end sub
private function check(byref eightqueenplace1(,) as int16, byval ii as int16, byref jj as int16)
dim x, y as int16
for i = 0 to topnum
for j = 0 to topnum
if eightqueenplace1(i, j) = 2 then
x = 0
y = 0
x = i - ii
y = j - jj
if abs(x) = abs(y) or abs(x) = 0 or abs(y) = 0 then
return 1
exit for
end if
end if
next
next
return 2
end function
private sub print(byref eightqueenplace1(,) as int16) '輸出符合條件的排列
for ii = 0 to topnum
for jj = 0 to topnum
textbox1.text = textbox1.text + " " + eightqueenplace1(ii, jj).tostring
next
textbox1.text = textbox1.text + chr(13) + chr(10)
next
textbox1.text = textbox1.text + chr(13) + chr(10)
end sub
private sub bu(byval eightqueenplace1(,) as int16, byval ii as int16, byref jj as int16, byval numm as int16) '遞迴
dim eightqueenplace(topnum, topnum) as int16
dim i as int16
dim j1 as int16
j1 = jj
for i = 0 to topnum
for j = 0 to topnum
eightqueenplace(i, j) = eightqueenplace1(i, j)
next
next
for i = ii to topnum
for j = j1 to topnum
if check(eightqueenplace, i, j) = 2 then
if j<>topnum then
eightqueenplace(i, j) = 1
bu(eightqueenplace, i, j + 1, numm) '能放但不放的分支
end if
numm = numm + 1
eightqueenplace(i, j) = 2
bu(eightqueenplace, i, j + 1, numm) '能放就放的分支
end if
next
j1 = 0
next
if i = topnum + 1 and numm > 7 and jj <> numm + 1 then '判斷是否符合條件
if j2 > (topnum * 2) * (topnum * 2) then exit sub
for j = 0 to (topnum * 2) * (topnum * 2) '判斷是否已經輸出過
printb = true
for a1 = 0 to topnum
for a2 = 0 to topnum
if eightqueenplace2(j, a1, a2) <> eightqueenplace(a1, a2) then
goto gggg
end if
next
next
printb = false
exit for
gggg:
next
if printb = true then '沒有輸出過，記錄下來
for a1 = 0 to topnum
for a2 = 0 to topnum
eightqueenplace2(j2, a1, a2) = eightqueenplace(a1, a2)
next
next
call print(eightqueenplace)
j2 = j2 + 1
end if
end if
end sub
end class
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