diff --git a/posseg/posseg.go b/posseg/posseg.go
index 6a431d6..d7996bd 100644
--- a/posseg/posseg.go
+++ b/posseg/posseg.go
@@ -128,15 +128,11 @@ func (p *Posseg) cutDAG(sentence string) chan WordTag {
 	go func() {
 		dag := p.DAG(sentence)
 		routes := p.Calc(sentence, dag)
-		x := 0
 		var y int
 		runes := []rune(sentence)
 		length := len(runes)
 		buf := make([]rune, 0)
-		for {
-			if x >= length {
-				break
-			}
+		for x := 0; x < length; {
 			y = routes[x].Index + 1
 			l_word := runes[x:y]
 			if y-x == 1 {
diff --git a/posseg/viterbi.go b/posseg/viterbi.go
index 580df76..1bccf8a 100644
--- a/posseg/viterbi.go
+++ b/posseg/viterbi.go
@@ -50,10 +50,10 @@ func viterbi(obs []rune) []string {
 			}
 		}
 		//use Go's map to implement Python's Set()
-		prev_states_expect_next := make(map[string]string)
+		prev_states_expect_next := make(map[string]int)
 		for _, x := range prev_states {
 			for y, _ := range probTrans[x] {
-				prev_states_expect_next[y] = y
+				prev_states_expect_next[y] = 1
 			}
 		}
 		tmp_obs_states := charStateTab.get(obs[t])