自定义函数-大数乘法

chenzyyysl

需要高精度计算的朋友可以试试
Function bigproduct(str1, str2)
Dim factor1(), factor2(), product()

len1 = Len(str1)
len2 = Len(str2)
ReDim factor1(len1)
ReDim factor2(len2)
ReDim product(len1 + len2)


For i = 0 To len1 - 1
factor1(i) = Right(Left(str1, len1 - i), 1)
Next
For j = 0 To len2 - 1
factor2(j) = Right(Left(str2, len2 - j), 1)
Next

For i = 0 To len1 - 1
  For j = 0 To len2 - 1
  pp = factor1(i) * factor2(j)
  product(i + j) = product(i + j) + (pp Mod 10)
  product(i + j + 1) = product(i + j + 1) + Int(pp / 10)
  Next j
Next i

For k = 0 To len1 + len2 - 1
product(k + 1) = product(k + 1) + Int(product(k) / 10)
product(k) = product(k) Mod 10
Next k

For k = len1 + len2 To 0 Step -1
If product(k) > 0 Then Exit For
product(k) = ""
Next k

For Each c In product
xxx = c & xxx
Next

bigproduct = xxx

End Function

一指禅

谢谢分享·~~~
学习啦

jinhaitiao16

谢谢分享·~~~ 学习啦

niko88819

好东西呢 收藏了！

huxy

谢谢分享·~~~
但没看懂，直接A*B，为什么要弄这么长？