40 lines
778 B
Go
40 lines
778 B
Go
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package kong
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import "unicode/utf8"
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// https://en.wikibooks.org/wiki/Algorithm_Implementation/Strings/Levenshtein_distance#Go
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// License: https://creativecommons.org/licenses/by-sa/3.0/
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func levenshtein(a, b string) int {
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f := make([]int, utf8.RuneCountInString(b)+1)
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for j := range f {
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f[j] = j
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}
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for _, ca := range a {
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j := 1
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fj1 := f[0] // fj1 is the value of f[j - 1] in last iteration
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f[0]++
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for _, cb := range b {
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mn := min(f[j]+1, f[j-1]+1) // delete & insert
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if cb != ca {
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mn = min(mn, fj1+1) // change
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} else {
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mn = min(mn, fj1) // matched
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}
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fj1, f[j] = f[j], mn // save f[j] to fj1(j is about to increase), update f[j] to mn
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j++
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}
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}
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return f[len(f)-1]
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}
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func min(a, b int) int {
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if a <= b {
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return a
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}
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return b
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}
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