100位數的大數相加

'100位數的大數相加
Public Class Form1
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim v1 = "12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890"
        Dim v2 = "13579086421357908642135790864213579086421357908642135790864213579086421357908642135790864213579086421357908642135790864213579086421357908642"

        Dim a(100) As Integer
        Dim b(100) As Integer
        Dim c(100) As Integer
        Dim d(100) As Integer

        '把代表大數的字串的每個數字，放入陣列中，a(1)代表個位數，a(2)代表十位數，餘類推
        For i = 1 To 100
            a(i) = Val(Mid(v1, 100 + 1 - i, 1))
            b(i) = Val(Mid(v2, 100 + 1 - i, 1))
        Next

        '從個位數加起
        c(0) = 0   '個位數，没有前一位進位狀況，設為0
        For i = 1 To 100
            d(i) = a(i) + b(i) + c(i - 1)
            c(i) = d(i) \ 10
            d(i) = d(i) Mod 10
        Next

        '輸出結果
        Dim rStr = ""
        If c(100) > 0 Then rStr = rStr & CStr(c(100))

        For i = 100 To 1 Step -1
            rStr = rStr & CStr(d(i))
        Next
        MsgBox(v1 & " + " & v2 & " = " & rStr)
        End
    End Sub
End Class

 

同學可先試試10位數的加、減、乘、除， 再推進到100位數，最後再改為1-100中的任何位數均可處理。

目前還做不出來也不用灰心，畢竟這是一般資訊相關科系，大二、大三資料結構的練習題目。