Ordered sequence: Difference between revisions
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'''Input:''' A key <math>K \in \kappa</math> and a nonnegative integral position <math>p</math>. | '''Input:''' A key <math>K \in \kappa</math> and a nonnegative integral position <math>p</math>. | ||
'''Output:''' a Boolean value, which is true if, and only if, <math>p\in\{0,\ldots,n\}</math>, where <math>n</math> is the length of the list. | '''Output:''' a Boolean value, which is '''true''' if, and only if, <math>p\in\{0,\ldots,n\}</math>, where <math>n</math> is the length of the list. | ||
'''Precondition:''' | '''Precondition:''' | ||
Revision as of 16:05, 16 May 2015
General Information
Representation invariant:
- The abstract data structure ordered sequence implements sorted sequences as defined here.
- This abstract data structure is generic and parameterized by a fixed key type [math]\displaystyle{ \kappa }[/math].
Insert at position
Input: A key [math]\displaystyle{ K \in \kappa }[/math] and a nonnegative integral position [math]\displaystyle{ p }[/math].
Output: a Boolean value, which is true if, and only if, [math]\displaystyle{ p\in\{0,\ldots,n\} }[/math], where [math]\displaystyle{ n }[/math] is the length of the list.
Precondition:
Postcondition: If the output ist true, a new element with the key [math]\displaystyle{ K }[/math] is inserted at position [math]\displaystyle{ p }[/math].
Find
Input: A key [math]\displaystyle{ K \in \kappa }[/math].
Output: A Boolean value, which is true if, and only if, [math]\displaystyle{ K }[/math] is currently contained in the sequence.
Precondition:
Postcondition:
Remove
Input: A key [math]\displaystyle{ K \in \kappa }[/math].
Output: A Boolean value, which is true if, and only if, [math]\displaystyle{ K }[/math] is currently stored in the sequence.
Precondition:
Postcondition: If the output is true, one occurrence of [math]\displaystyle{ K }[/math] is removed.