Excel VBA求定积分的程序运行的不到结果 代码如下

Sub testl()
Dim a As Double
Dim b As Double
Dim lnA As Long
Dim lnB As Long
Dim M As Double
Dim lnM As Long
Dim n As Long
Dim n0 As Long
Dim X As Double
Dim Y As Double
a = InputBox("请输入积分下限a", "积分下限", "")
b = InputBox("请输入积分上限b", "积分上限", "")
n = InputBox("请输入模拟投点的次数n", "模拟投点的次数", "")
M = Exp(a) + Exp(b)
Dim tmp, xs As Integer
xs = 1
If a > b Then
tmp = a
a = b
b = tmp
xs = -1
End If
lnA = a * 10 ^ 6: lnB = b * 10 ^ 6: lnM = M * 10 ^ 6
Dim i
Dim tmpY As Double
i = 1
Do While i <= n
Randomize
X = Int((lnB - lnA + 1) * Rnd + lnA) / 10 ^ 6
Y = Int((lnM - 0 + 1) * Rnd + 0) / 10 ^ 6
tmpY = Exp(X)
If tmpY >= Y Then
nO = n0 + 1
End If
i = i + 1
Loop
MsgBox xs * M * (b - a) * n0 / n
End Sub
得到的结果一直是0

Sub testl()
Dim a As Double
Dim b As Double
Dim lnA As Long
Dim lnB As Long
Dim M As Double
Dim lnM As Long
Dim n As Long
Dim n0 As Long
Dim X As Double
Dim Y As Double
a = InputBox("请输入积分下限a", "积分下限", "")
b = InputBox("请输入积分上限b", "积分上限", "")
n = InputBox("请输入模拟投点的次数n", "模拟投点的次数", "")
M = Exp(a) + Exp(b)
Dim tmp, xs As Integer
xs = 1
If a > b Then
  tmp = a
  a = b
  b = tmp
  xs = -1
End If
lnA = a * 10 ^ 6: lnB = b * 10 ^ 6: lnM = M * 10 ^ 6
Dim i
Dim tmpY As Double
i = 1
Do While i <= n
  Randomize
  X = Int((lnB - lnA + 1) * Rnd + lnA) / 10 ^ 6
  Y = Int((lnM - 0 + 1) * Rnd + 0) / 10 ^ 6
  tmpY = Exp(X)
  If tmpY >= Y Then
    n0 = n0 + 1
  End If
  i = i + 1
Loop
MsgBox xs * M * (b - a) * n0 / n
End Sub上面是修改正确的代码，请全选、粘贴测试。

function f1(li,aa,pa,pb.l) for i = 0 to li x = sin((aa+pa*l+(pb-pa)*(l^2/l))*(pi()/180)) f1 = f1 + x next end function function f2(li,aa,pa,pb.l) for i = 0 to li x = cos((aa+pa*l+(pb-pa)*(l^2/l))*(pi()/180)) f1 = f1 + x next end function