diff --git a/cmd/main.go b/cmd/main.go
new file mode 100644
index 0000000..eb958b6
--- /dev/null
+++ b/cmd/main.go
@@ -0,0 +1,23 @@
+package main
+
+import (
+	"fmt"
+	"unicode/utf8"
+)
+
+func main() {
+	b := []byte("你好")
+
+	sz := 0
+	var r rune
+
+	for i := 0; i < len(b); {
+		r, sz = utf8.DecodeRune(b[i:])
+		i += sz
+
+		fmt.Println(r, sz, i, string(r))
+	}
+
+	// fmt.Println(len(b))
+
+}
diff --git a/machines/machine.go b/machines/machine.go
index e60ccff..b6325b0 100644
--- a/machines/machine.go
+++ b/machines/machine.go
@@ -69,36 +69,35 @@ type Match struct {
 	Bytes       []byte // the actual bytes matched during scanning.
 }
 
-func computeLineCol(s []byte, prevTC, tc, line, col int) (int, int) {
-	// s := []rune(string(text))
+func computeLineCol(text []byte, prevTC, tc, line, col int) (int, int) {
 	if tc < 0 {
 		return line, col
 	}
 	if tc < prevTC {
 		for i := prevTC; i > tc && i > 0; i-- {
-			if s[i] == '\n' {
+			if text[i] == '\n' {
 				line--
 			}
 		}
 		col = 0
 		for i := tc; i >= 0; i-- {
-			if s[i] == '\n' {
+			if text[i] == '\n' {
 				break
 			}
 			col++
 		}
 		return line, col
 	}
-	for i := prevTC + 1; i <= tc && i < len(s); i++ {
-		if s[i] == '\n' {
+	for i := prevTC + 1; i <= tc && i < len(text); i++ {
+		if text[i] == '\n' {
 			col = 0
 			line++
 		} else {
 			col++
 		}
 	}
-	if prevTC == tc && tc == 0 && tc < len(s) {
-		if s[tc] == '\n' {
+	if prevTC == tc && tc == 0 && tc < len(text) {
+		if text[tc] == '\n' {
 			line++
 			col--
 		}