vb.net - Getting a null reference exception trying to push a zero to a stack -


well on last day of school trying finish program , can't life of me past null reference exception. code supposed average [count] numbers entered user using stack of integers. throwing null reference exception because attempted count of stack empty, added line push 0 on it. program stops @ line same error (nullreferenceexception). if change stack accept strings works fine, need accept integers. can :)

module module1      sub main()         dim count integer = 16         dim stack new stack(of integer)         stack.push(0)         console.writeline("please enter " & count & " numbers")         while stack.count - 1 = count             stack.push(console.readline)             if not isnumeric(stack.peek)                 console.writeline(stack.pop & " not number please try again.")             end if         loop     end sub  end module

you're declaring variable named stack, not creating stack object. instead (with new keyword):

dim stack new stack(of integer)

without new, variable contain null reference, why getting nullreferenceexception whenever attempt variable.


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