allowed file to be entered as argument

main.go

@@ -21,10 +21,18 @@ func main() {
 	Error(err)
 
 	// Get name of file to be processed.
-	pterm.Printf(pterm.Cyan("What is the name of the file in this directory?: "))
-	reader := bufio.NewReader(os.Stdin)
-	input, err := reader.ReadString('\n')
-	Error(err)
+	args := os.Args[1:]
+
+	var input string
+
+	if len(args) > 0 {
+		input = args[0]
+	} else {
+		pterm.Printf(pterm.Cyan("What is the name of the file in this directory?: "))
+		reader := bufio.NewReader(os.Stdin)
+		input, err = reader.ReadString('\n')
+		Error(err)
+	}
 
 	// Create upcs array and push all upc strings into it
 	input = strings.TrimSpace(input)