Private Sub Command1_Click()
    'PROGRAM D4R2
    'Driver for routine FACTRL
    Open "D:\VB常用數(shù)值算法集\DATA\FNCVAL.DAT" For Input As #1
    Do
      Line Input #1, Text$
    Loop While Text$ <> "N-factorial"
    Line Input #1, NVAL$
    NVAL = Val(NVAL$)
       Print Text$
    Print
    Print "   N         Actual             FACVAL(N)"
    For I = 1 To NVAL
        Line Input #1, DUM$
        N = Val(Mid(DUM$, 1, 2))
        ACTUAL = Val(Mid(DUM$, 8))
        If ACTUAL < 10000000000# Then
            Print Tab(4); Format$(N, "##0");
            Print Tab(14); Format$(ACTUAL, "#########.");
            Print Tab(33); Format$(FACTRL(N), "########.")
        Else
            Print Tab(4); Format$(N, "##0");
            Print Tab(14); Format$(ACTUAL, ".######0E+00");
            Print Tab(33); Format$(FACTRL(N), ".######0E+00")
        End If
    Next I
    Close #1
End Sub