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levenshtein

Written By 1 on Sunday, September 30, 2012 | 10:04 AM

int levenshtein ( string $str1 , string $str2 )

Calculate Levenshtein distance between two strings

The Levenshtein distance is defined as the minimal number of characters you have to replace, insert or delete to transform str1 into str2. The complexity of the algorithm is O(m*n), where n and m are the length of str1 and str2 (rather good when compared


<?php
// input misspelled word
$input 'carrrot';

// array of words to check against
$words  = array('apple','pineapple','banana','orange',
                
'radish','carrot','pea','bean','potato');

// no shortest distance found, yet
$shortest = -1;

// loop through words to find the closest
foreach ($words as $word) {

    
// calculate the distance between the input word,
    // and the current word
    
$lev levenshtein($input$word);

    
// check for an exact match
    
if ($lev == 0) {

        
// closest word is this one (exact match)
        
$closest $word;
        
$shortest 0;

        
// break out of the loop; we've found an exact match
        
break;
    }

    
// if this distance is less than the next found shortest
    // distance, OR if a next shortest word has not yet been found
    
if ($lev <= $shortest || $shortest 0) {
        
// set the closest match, and shortest distance
        
$closest  $word;
        
$shortest $lev;
    }
}

echo 
"Input word: $input\n";
if (
$shortest == 0) {
    echo 
"Exact match found: $closest\n";
} else {
    echo 
"Did you mean: $closest?\n";
}

?>


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