Use min() builtin function, update Go minimum version to 1.21

benchstat does not indicate any performance regression.

goos: linux
goarch: amd64
pkg: github.com/agnivade/levenshtein
cpu: AMD Ryzen 7 7840U w/ Radeon  780M Graphics
                       │ before.txt  │             after.txt              │
                       │   sec/op    │   sec/op     vs base               │
Simple/ASCII-16          134.3n ± 0%   134.5n ± 0%       ~ (p=0.135 n=20)
Simple/French-16         253.8n ± 0%   253.5n ± 0%       ~ (p=0.155 n=20)
Simple/Nordic-16         499.4n ± 0%   498.1n ± 0%  -0.26% (p=0.005 n=20)
Simple/long_string-16    1.853µ ± 0%   1.852µ ± 0%       ~ (p=0.878 n=20)
Simple/Tibetan-16        414.3n ± 0%   414.4n ± 0%       ~ (p=0.952 n=20)
All/ASCII/agniva-16      136.4n ± 0%   136.4n ± 0%       ~ (p=0.941 n=20)
All/ASCII/arbovm-16      193.0n ± 0%   192.6n ± 0%       ~ (p=0.151 n=20)
All/ASCII/dgryski-16     198.6n ± 0%   198.8n ± 1%       ~ (p=0.292 n=20)
All/French/agniva-16     255.9n ± 0%   255.9n ± 0%       ~ (p=0.899 n=20)
All/French/arbovm-16     332.1n ± 0%   331.6n ± 0%       ~ (p=0.857 n=20)
All/French/dgryski-16    333.2n ± 0%   333.1n ± 0%       ~ (p=0.732 n=20)
All/Nordic/agniva-16     500.1n ± 0%   499.9n ± 0%       ~ (p=0.673 n=20)
All/Nordic/arbovm-16     604.1n ± 0%   606.6n ± 0%  +0.41% (p=0.041 n=20)
All/Nordic/dgryski-16    612.4n ± 0%   612.4n ± 0%       ~ (p=0.984 n=20)
All/Tibetan/agniva-16    414.4n ± 0%   414.5n ± 0%       ~ (p=0.753 n=20)
All/Tibetan/arbovm-16    501.4n ± 1%   499.1n ± 1%       ~ (p=0.262 n=20)
All/Tibetan/dgryski-16   504.9n ± 0%   504.8n ± 0%       ~ (p=0.888 n=20)
geomean                  365.7n        365.6n       -0.03%

go.mod

@@ -1,6 +1,6 @@
 module github.com/agnivade/levenshtein
 
-go 1.13
+go 1.21
 
 require (
 	github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0

levenshtein.go

@@ -71,7 +71,7 @@ func ComputeDistance(a, b string) int {
 		for j := 1; j <= lenS1; j++ {
 			current := x[j-1] // match
 			if s2[i-1] != s1[j-1] {
-				current = min(min(x[j-1]+1, prev+1), x[j]+1)
+				current = min(x[j-1]+1, prev+1, x[j]+1)
 			}
 			x[j-1] = prev
 			prev = current
@@ -80,10 +80,3 @@ func ComputeDistance(a, b string) int {
 	}
 	return int(x[lenS1])
 }
-
-func min(a, b uint16) uint16 {
-	if a < b {
-		return a
-	}
-	return b
-}