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Array Functions Summary
The good news is that QBasic support arrays. The bad news is that the support is fairly minimal, with only a handful of functions available.

Properties	ubound, lbound
Assignment	erase
Declaration	option base

Array Code Snippets
The following code shows several methods of manipulating arrays.

     Dim x$(5)         # declare array
     Dim x$(5,1)       # declare two-dimensional array

     x$(1) = "hello"   # assigns value to array element 1
    
     erase x$          # clears an array

Array Functions Reference
Here's a quick reference of the available array functions, in alphabetical order.

• ubound - returns upper array index

      Dim x(5), y(5,7)
      result = ubound(x)            # returns 5
      result = ubound(x,2)          # returns 7
      

• lbound - returns lower array index

      Dim x(-7 to 5, 4 to 6)
      result = lbound(x)            # returns -7
      result = lbound(x,2)          # returns 4
      

• erase - reset all values of the array

      Dim x(5)       # create array x
      x(1) = 2       # x(1) is set to 2
      erase x        # x(1) is now = 0
      

• option base - set lower array index of all arrays to 0 or 1

      option base 0         # sets lower index of arrays to 0
      Dim x(5)              # lower index of x is 5
      option base 1         # sets lower index of arrays to 1
      Dim x(5)              # lower index of x is 1
      

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