update book code

eBook/exercises/chapter_6/varargs.go

@@ -0,0 +1,23 @@
+// Q10_varargs.go
+package main
+
+import (
+	"fmt"
+)
+
+func main() {
+	printInts()
+	println()
+	printInts(2, 3)
+	println()
+	printInts(0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
+}
+
+func printInts(list ...int) {
+//	for i:=0; i<len(list); i++ {
+//		fmt.Printf("%d\n", list[i])
+//	}
+	for _, v := range list {
+		fmt.Printf("%d\n", v)
+	}
+}