added yamltool sort

cmd/lcstest/main.go

@@ -0,0 +1,137 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"time"
+)
+
+// from: https://github.com/peter-evans/patience/blob/main/lcs.go
+func LCS[T comparable](a, b []T, equals func(T, T) bool) [][2]int {
+	// Initialize the LCS table.
+	lcs := make([][]int, len(a)+1)
+	for i := 0; i <= len(a); i++ {
+		lcs[i] = make([]int, len(b)+1)
+	}
+
+	// Populate the LCS table.
+	for i := 1; i < len(lcs); i++ {
+		for j := 1; j < len(lcs[i]); j++ {
+			if equals(a[i-1], b[j-1]) {
+				lcs[i][j] = lcs[i-1][j-1] + 1
+			} else {
+				lcs[i][j] = max(lcs[i-1][j], lcs[i][j-1])
+			}
+		}
+	}
+
+	// Backtrack to find the LCS.
+	i, j := len(a), len(b)
+	s := make([][2]int, 0, lcs[i][j])
+
+	for i > 0 && j > 0 {
+		switch {
+		case equals(a[i-1], b[j-1]):
+			s = append(s, [2]int{i - 1, j - 1})
+			i--
+			j--
+		case lcs[i-1][j] > lcs[i][j-1]:
+			i--
+		default:
+			j--
+		}
+	}
+
+	// Reverse the backtracked LCS.
+	for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 {
+		s[i], s[j] = s[j], s[i]
+	}
+
+	return s
+}
+
+func LCSDiff[T comparable](a, b []T, equals func(T, T) bool,
+	diff func(T), same func(T, T)) {
+	res := LCS(a, b, equals)
+
+	i2 := 0
+	isame := 0
+	for isame < len(res) {
+		// process [i1..isamee1[ and [i2..isame2[
+		for i2 < res[isame][1] {
+			diff(b[i2])
+			i2++
+		}
+		// process same elements -> no diff so normally not
+		same(a[res[isame][0]], b[res[isame][1]])
+		i2++
+		isame++
+	}
+	for i2 < len(b) {
+		diff(b[i2])
+		i2++
+	}
+}
+
+const letters = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+
+func randString(n int) string {
+	res := make([]byte, n)
+	for i := range n {
+		res[i] = letters[rand.Int()%len(letters)]
+	}
+	return string(res)
+}
+
+func main() {
+	input1 := []string{"ab", "cd", "myidenticalstring"}
+	input2 := []string{"ab", "ce", "myidenticalstrings", "fg"}
+	t0 := time.Now()
+	res := LCS(input1, input2, func(s1 string, s2 string) bool {
+		res := LCS([]rune(s1), []rune(s2), func(r rune, r2 rune) bool {
+			return r == r2
+		})
+		score := min(float64(len(res))/float64(len(s1)),
+			float64(len(res))/float64(len(s2)))
+		return score > 0.90
+	})
+	dt := time.Now().Sub(t0).Microseconds()
+	fmt.Printf("time %v us, len %v\n", dt, len(res))
+	for i, pair := range res {
+		fmt.Printf("%d: %v\n", i, pair)
+	}
+
+	// [0..i1[ and [0..i2[ already handled
+	// isame: res[0..isame[ have been handled
+	//i1 := 0
+	i2 := 0
+	isame := 0
+	for isame < len(res) {
+		// process [i1..isamee1[ and [i2..isame2[
+		for i2 < res[isame][1] {
+			fmt.Printf("DIFF|ADD %s\n", input2[i2])
+			i2++
+		}
+		// process same elements -> no diff so normally not
+		fmt.Printf("SAME     %s %s\n", input1[res[isame][0]], input2[res[isame][1]])
+		i2++
+		isame++
+	}
+	for i2 < len(input2) {
+		fmt.Printf("DIFF|ADD %s\n", input2[i2])
+		i2++
+	}
+
+	LCSDiff(input1, input2, func(s1 string, s2 string) bool {
+		res := LCS([]rune(s1), []rune(s2), func(r rune, r2 rune) bool {
+			return r == r2
+		})
+		score := min(float64(len(res))/float64(len(s1)),
+			float64(len(res))/float64(len(s2)))
+		return score > 0.90
+	}, func(s string) {
+		fmt.Printf("DIFF %v\n", s)
+	}, func(s1 string, s2 string) {
+		fmt.Printf("SAME %v %v\n", s1, s2)
+	})
+}