vb编写程序,计算s=1+(1+2)+(1+2+3)+…+(1+2+3+…+n)

Private Sub Command1_Click()Dim n As IntegerDim sum As DoubleDim Tsum As IntegerTsum = 0sum = 0n = InputBox("请输入数字N")For i = 1 To n Tsum = Tsum + i sum = sum + TsumNext iPrint sumEnd Sub