You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: convert_octal_to_hexadecimal.go
    path of file: ./repos/program/program/convert-octal-to-hexadecimal
    
    the code of the file until where you have to start completion: package main

import (
	"fmt"
	"strconv"
	"strings"
)

func main() {

	var octalStr string
	fmt.Println("Enter octal number")
	fmt.Scanln(&octalStr)

	// convert an octal str to a decimal number
	decimalNum, err
    
func main() {

	var octalStr string
	fmt.Println("Enter octal number")
	fmt.Scanln(&octalStr)

	// convert an octal str to a decimal number
	decimalNum, err := strconv.ParseInt(octalStr, 8, 64)
	if err != nil {
		fmt.Println("error occur when parse octal num")
		return
	}

	// Convert a decimal number to a hexadecimal number
	hexStr := strconv.FormatInt(decimalNum, 16)

	fmt.Printf("octal number %s converted to hexadecimal numberï¼š%s\n", octalStr, strings.ToUpper(hexStr))
}