ShareDAV/vendor/github.com/alecthomas/kong/levenshtein.go

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