diff --git a/eBook/exercises/chapter_11/min_interface.go b/eBook/exercises/chapter_11/min_interface.go
index eabfe31a5..52a3891d6 100755
--- a/eBook/exercises/chapter_11/min_interface.go
+++ b/eBook/exercises/chapter_11/min_interface.go
@@ -5,16 +5,19 @@ type Miner interface {
 	Len() int
 	ElemIx(ix int) interface{}
 	Less(i, j int) bool
+	Swap(i, j int)
 }
 
 func Min(data Miner) interface{} {
-	j := 0
+  min := data.ElemIx(0)
 	for i := 1; i < data.Len(); i++ {
-		if data.Less(i, j) {
-			j = i
+		if data.Less(i, i-1) {
+			min = data.ElemIx(i)
+		} else {
+			data.Swap(i, i-1)
 		}
 	}
-	return data.ElemIx(j)
+	return min
 }
 
 type IntArray []int
@@ -22,9 +25,11 @@ type IntArray []int
 func (p IntArray) Len() int                  { return len(p) }
 func (p IntArray) ElemIx(ix int) interface{} { return p[ix] }
 func (p IntArray) Less(i, j int) bool        { return p[i] < p[j] }
+func (p IntArray) Swap(i, j int)             { p[i], p[j] = p[j], p[i] }
 
 type StringArray []string
 
 func (p StringArray) Len() int                  { return len(p) }
 func (p StringArray) ElemIx(ix int) interface{} { return p[ix] }
 func (p StringArray) Less(i, j int) bool        { return p[i] < p[j] }
+func (p StringArray) Swap(i, j int)             { p[i], p[j] = p[j], p[i] }