Chapter 9 One-Dimensional Arrays

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Chapter 9One-Dimensional Arrays
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Chapter 9

• An array is an indexed data structure that is
  used to store data elements of the same data
  type.

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Chapter 9

• A one-dimensional array, or list, is a sequential
  list of storage locations that contain data
  elements that are located via indices.

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Chapter 9

• One-Dimensional Array Definition Format
• element data type array nameSIZE

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Chapter 9

• Inserting an Array Element Using Direct
  Assignment
• array name index element value

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Chapter 9

• Inserting Array Elements Using a for Loop
• for(int index0indexltarray size index)
• assign or read to arrayindex

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Chapter 9

• Copying an Array Element Using Direct Assignment
  
• variable array nameindex

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Chapter 9

• Displaying Array Elements Down the Screen Using
  a for Loop
• for(int index0indexltarray size index)
• cout ltlt arrayindex ltlt endl

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Chapter 9

• C-stings are stored in character arrays where the
  last element of the string is always the \0
  null terminator character.

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Chapter 9

• C-String Definition with a Specified Size
• char variable identifiermaximum size of
  string 1 \0

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Chapter 9

• C-String Definition without a Specified Size
• char variable identifier "string value"

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Chapter 9

• Reading C-Strings Using getline()
• cin.getline(array ident., array size,
• 'delimiting character')

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Chapter 9

• C-String Functions
• strcat() string.h Appends one string to
  another.
• strcmp() string.h Compares two strings.
• strlen() string.h Returns length of a
  string.
• strcpy() string.h Copies a string.

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Chapter 9

• Sequential SearchSet found false.
• Set index first array index.
• While (element is not found) AND (index lt last
  array index)
• If (arrayindex element) Then
• Set found true.
• Else
• Increment index.
• If (found true)
• Return index.
• Else
• Return 1.
• .

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Chapter 9

• Insertion Sort
• Set i second array index.
• While (i lt last array index)
• Set j i.
• While ( (j gt first array index) AND
  (arrayj lt arrayj 1) )
• Exchange arrayj and arrayj 1.
• Decrement j.
• Increment i.

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Chapter 9

• teleSearch()
• BEGIN
• If (the telephone book only contains one page)
• Look for the name on the page.
• Else
• Open the book to the middle.
• If (the name is in the first half)
• teleSearch(first half of the book for the
  name).
• Else
• teleSearch(second half of the book for the
  name).
• END.

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Chapter 9

• Recursive Binary Search (initial algorithm)
• binSearch()
• If (the array has only one element)
• Determine if this the element.
• Else
• Find the midpoint of the array.
• If (the element is in the first half)
• binSearch(first half).
• Else
• binSearch(second half).

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Chapter 9

• Recursive Binary Search (final algorithm)If
  (first gt last)
• Return 1.
• Else
• Set mid (first last) / 2.
• If (arraymid element)
• Return mid.
• Else
• If (the element is in the first half)
• binSearch(array, element, first, mid 1).
• Else
• binSearch(array, element, mid 1, last).

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Chapter 9

• Method binSearch()Searches a sorted array of
  integers for a given value.
• Accepts An array of integers, an element for
  which to search, the first index of the array
  being searched, and the last index of the array
  being searched.
• Returns The array index of the element, if
  found, or the value 1 if the element is not
  found.
• int binSearch(int array, int element, int
  first, int last)

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Chapter 9
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Chapter 9

• int binSearch(int array , int element, int
  first, int last)
• int mid //ARRAY MIDPOINT
• if (first gt last) //IF ELEMENT NOT IN ARRAY
• return -1 //RETURN -1, ELSE CONTINUE
• else
• mid (first last) / 2 //FIND
  MIDPOINT OF ARRAY
• if (element arraymid) //IF ELEMENT IS
  IN ARRAYMID
• return mid //RETURN MID
• else //ELSE SEARCH APPROPRIATE HALF
• if (element lt arraymid)
• return binSearch(array, element, first, mid
  - 1)
• else
• return binSearch(array, element,
  mid 1, last)
• //END OUTER ELSE
• //END binSearch()

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Chapter 9

• The C Standard Template Library, or STL,
  contains a class called vector that can be used
  to build and manipulate one-dimensional arrays.

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Chapter 9

• Defining a Vector Example//INTEGER VECTOR, SIZE
  10, //INITIALIZED TO 0s
• vectorltintgt v1(10,0)

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Chapter 9

• STL Vector Class Functions
• void begin()
• Places iterator at beginning of the vector.
• vector data type back()
• Returns, but does not remove, the last element
  of the vector.
• bool empty()
• Returns true if vector is empty.
• void end()
• Places iterator at end of the vector.
• vector data type front()
• Returns, but does not remove, the first element
  of the vector.
• void pop_back()
• Removes, but does not return, the last element
  of the vector.

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Chapter 9

• STL Vector Class Functions
• void begin()
• Places iterator at beginning of the vector.
• vector data type back()
• Returns, but does not remove, the last element
  of the vector.
• bool empty()
• Returns true if vector is empty.

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Chapter 9

• STL Vector Class Functions (continued)
• void end()
• Places iterator at end of the vector.
• vector data type front()
• Returns, but does not remove, the first element
  of the vector.
• void pop_back()
• Removes, but does not return, the last element
  of the vector.

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Chapter 9

• STL Vector Class Functions (continued)
• void push_back(element)
• Places element at the end of the vector.
• int size()
• Returns the number of elements in the vector.