Difference between revisions of "Linear Search"

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(Created page with "Linear search is a very simple search algorithm. In this type of search, a sequential search is made over all items one by one. Every item is checked and if a match is found t...")
 
(Added python code because I'm lazy to write in C#)
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{{Need_Expanding}}
 
Linear search is a very simple search algorithm. In this type of search, a sequential search is made over all items one by one. Every item is checked and if a match is found then that particular item is returned, otherwise the search continues till the end of the data collection.
 
Linear search is a very simple search algorithm. In this type of search, a sequential search is made over all items one by one. Every item is checked and if a match is found then that particular item is returned, otherwise the search continues till the end of the data collection.
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Here's a simple example in Python 3.
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<syntaxhighlight lang="python" line>
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ar = [["A", 1], ["B", 2], ["C", 3], ["D", 4], ["E", 5]];
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##Array to be searched
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def linearSearch(arr, toFind):
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    for x in arr: ##Goes by element 1 by 1
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        if  x[0] == toFind: return x[1]; ##If you find the item, return the value.
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    return None; #If you don't, return None for nothing.
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print ( "Looking for 'A'", linearSearch(ar, "A") );
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print ( "Looking for 'E'", linearSearch(ar, "E") );
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print ( "Looking for 'l'", linearSearch(ar, "l") );
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##Return:
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##Looking for 'A' 1
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##Looking for 'E' 5
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##Looking for 'l' None
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</syntaxhighlight>

Revision as of 21:56, 19 March 2017

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Linear search is a very simple search algorithm. In this type of search, a sequential search is made over all items one by one. Every item is checked and if a match is found then that particular item is returned, otherwise the search continues till the end of the data collection.

Here's a simple example in Python 3.

 1 ar = [["A", 1], ["B", 2], ["C", 3], ["D", 4], ["E", 5]];
 2 ##Array to be searched
 3 
 4 def linearSearch(arr, toFind):
 5     for x in arr: ##Goes by element 1 by 1
 6         if  x[0] == toFind: return x[1]; ##If you find the item, return the value.
 7     return None; #If you don't, return None for nothing.
 8 
 9 print ( "Looking for 'A'", linearSearch(ar, "A") );
10 print ( "Looking for 'E'", linearSearch(ar, "E") );
11 print ( "Looking for 'l'", linearSearch(ar, "l") );
12 
13 ##Return:
14 ##Looking for 'A' 1
15 ##Looking for 'E' 5
16 ##Looking for 'l' None