Multidimensional Arrays

1
Multidimensional Arrays
2
Syntax

• Type name d1d2d3 init list
• int X 3 4 5
• Leftmost subscript varies most slowly known as
  row major order

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Arrays as arguments

• function X (int x, int y, int a x y) ...
• Not valid in MANY C compilers
• New standard as of 1999 implemented ???
• function X (int a 7) ... // valid
• highest dimension is still required

4
Dynamic arrays (1)

• Requires the use of the new operator
• Syntax new Type amount
• int ptr // a ptr to an array of int's
• ptr new int5 // note constant size
• if (dptrNULL) is better than if (dptr0)

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Dynamic arrays (2)

• int y
• cingtgty
• int ptr // a ptr to an array of int's
• ptr new inty // note size determined at
  //run time
• BUT the size of the array is still FIXED

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Deleting storage

• Given the previous array delete ptr //
  deletes a SINGLE datum
• the one memory loc that ptr refers to
• Even if it's an array (only deletes array0)
• delete ptr // deletes the whole array

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Strings

• C-style strings (array of char)
• char x xnew char n
• Or
• Using namespace std
• include ltcstringgt
• C style (true) strings
• include ltstring.hgt
• or
• using namespace std
• include ltstringgt