Linear Search

1
Linear Search

• Is target in the array?

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• void ReadArray(float s, int size)
• int main()
• int count
• float MyArray50, target
• ReadArray(MyArray, count)
• // Assume count is 8
• // Is 51 in the array?
• // Is 60 in the array?
• cin gtgt target
• // Is target in the array?
• // Linear search!
• return 0

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3
Linear Search FunctionFind Target in an Array

• The function returns true if target is found in
  the array,
• false otherwise.
• Function Prototype
• Function Name
• SearchArray
• Function Type
• bool (true/false)
• Function parameters
• floatArray array of type float
• size int, number of
  elements of floatArray
• target a float number
• In, Out, InOut?
• bool SearchArray(const float floatArray, int
  size, float target)

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• //------------------------------------------------
  -------------------
• // The function has three parameters
• // floatArray array of type float
• // size int, number of elements of
  floatArray
• // target a float number
• // The function returns true if target is found
  in floatArray,
• // false otherwise.
• // Parameters (in, in, in)
• //------------------------------------------------
  -------------------
• bool SearchArray(const float floatArray, int
  size, float target)
• for (int i 0 i lt size i)
• if (floatArrayi target)
• return true
• else
• // ?
• // When to return false?

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• //------------------------------------------------
  
• // The function has three parameters
• // floatArray array of type float
• // size int, number of elements of
• // floatArray
• // target a float number
• // The function returns a bool value
• // true if target is found in floatArray,
• // false otherwise.
• // Parameters (in, in, in)
• //------------------------------------------------
  
• bool SearchArray(const float floatArray,
• int size, float target)
• for (int i 0 i lt size i)
• if (floatArrayi target)
• return true

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• //------------------------------------------------
  
• // The function has three parameters
• // floatArray array of type float
• // size int, number of elements of
• // floatArray
• // target a float number
• // The function returns a bool value
• // true if target is found in floatArray,
• // false otherwise.
• // Parameters (in, in, in)
• //------------------------------------------------
  
• bool SearchArray(const float floatArray,
• int size, float target)
• for (int i 0 i lt size i)
• if (i target)
• return true

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• void ReadArray(float s, int size)
• bool SearchArray(const float floatArray, int
  size, float target)
• int main()
• float MyArray50, target
• int count
• ReadArray(MyArray, count)
• cin gtgt target
• while (!cin.eof())
• if (SearchArray(MyArray, count, target))
• cout ltlt Value ltlt target ltlt is in
  the array.
• else
• cout ltlt Value ltlt target ltlt is NOT
  in the array.
• cin gtgt target
• return 0

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• void ReadArray(float s, int size)
• bool SearchArray(const float floatArray, int
  size, float target)
• int main()
• float MyArray50, target
• int count
• bool found
• ReadArray(MyArray, count)
• cin gtgt target
• while (!cin.eof())
• found SearchArray(MyArray, count,
  target)
• if (found)
• cout ltlt Value ltlt target ltlt is in
  the array.
• else
• cout ltlt Value ltlt target ltlt is NOT
  in the array.
• cin gtgt target
• return 0

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Linear Search

• Is target in the array?
• Check array elements one at a time.

10
Linear Search

• Find the Largest Value
• of All Array Element

11

• Find the Largest Value of All Array Elements
• Function Prototype
• Function Name
• MaxArrayValue
• Function Type
• float (int)
• Same as the array type
• Function parameters
• s array of int
• size int, number of elements in s
• In, Out, InOut?
• // Parameters (in, in)
• int MaxArrayValue(const int s, int size)

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• //------------------------------------------------
  -----------
• // The function has two parameters
• // s array of int
• // size int, number of elements in s
• // The function finds and returns the largest
  array element
• // of s, assuming size is positive and in
  the range.
• // Parameters (in, in)
• //------------------------------------------------
  -----------
• int MaxArrayValue(const int s, int size)
• int Max
• Max s0
• for (int i 1 i lt size i )
• if (si gt Max)
• Max si
  
• return Max

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• Quiz5
• Part III
• Due 5 pm Wednesday
• Part IV
• Due 5 PM Friday

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This Week

• Thursday
• Lab 7
• Friday
• Lab 206 to do Prog3 and Quiz (Lab)

15
Program 3

• Due Date 930 PM Friday
• Program 4
• Paring Sign Sheet
• Test 2
• Week 10