How do I get the code to exit if someone hit cancel on the input box



strjobnumber = InputBox("Start in Job Number?", " First Job to Print",
0)
endjobnumber = InputBox("Finish in Job Number?", " Last Job to
Print", 0)




Sub doprint()
'
' doprint Macro


Dim i As Integer
Dim oCell As Range
Dim cCell As Range
Dim p As Long

strjobnumber = InputBox("Start in Job Number?", " First Job to
Print", 0)
endjobnumber = InputBox("Finish in Job Number?", " Last Job to
Print", 0)

Range("I40").Select
Range("I41").Select


For counter = strjobnumber To endjobnumber
Application.ScreenUpdating = False
Sheets("Pieces").Activate
Range("L5").Value = counter
Range("J85").Select
c = ActiveCell.Value

If c < 100 Then GoTo NextCounter

Range("J80").Select
p = ActiveCell.Value
Sheets(Array("BatchSheet1", "BatchSheet2", "BatchSheet3",
"BatchSheet4", _
"BatchSheet5", "BatchSheet6", "BatchSheet7", "BatchSheet8",
"BatchSheet9", _
"BatchSheet10", "BatchSheet11", "BatchSheet12",
"BatchSheet13", "BatchSheet14", _
"BatchSheet15", "BatchSheet16", "BatchSheet17",
"BatchSheet18", "BatchSheet19", _
"BatchSheet20")).Select
Sheets("BatchSheet1").Activate
ActiveWindow.SelectedSheets.PrintOut From:=1, To:=p,
Copies:=1, Collate _
:=True
Application.ScreenUpdating = True
NextCounter:
Next counter
Sheets("Pieces").Activate
Range("$A$1").Select

End Sub