hamming.go

func hexToBinary(hexnum string) string {
	if hexnum == "0" {
		return "0000"
	} else if hexnum == "1" {
		return "0001"
	} else if hexnum == "2" {
		return "0010"
	} else if hexnum == "3" {
		return "0011"
	} else if hexnum == "4" {
		return "0100"
	} else if hexnum == "5" {
		return "0101"
	} else if hexnum == "6" {
		return "0110"
	} else if hexnum == "7" {
		return "0111"
	} else if hexnum == "8" {
		return "1000"
	} else if hexnum == "9" {
		return "1001"
	} else if hexnum == "a" || hexnum == "A" {
		return "1010"
	} else if hexnum == "b" || hexnum == "B" {
		return "1011"
	} else if hexnum == "c" || hexnum == "C" {
		return "1100"
	} else if hexnum == "d" || hexnum == "D" {
		return "1101"
	} else if hexnum == "e" || hexnum == "E" {
		return "1110"
	} else {
		return "1111"
	}
}

// THIS FUNCTION TAKES HEX STRING REPRESENTATIONs OF THE TWO STRINGS AS ARGUMENTS
func hamming(s1 string, s2 string) int {
	//hex1 := fmt.Sprintf("%x", s1)
	//hex2 := fmt.Sprintf("%x", s2)

	bytes_s1, _ := hex.DecodeString(s1)
	bytes_s2, _ := hex.DecodeString(s2)

	bytes_str1 := fmt.Sprintf("%x", bytes_s1)
	bytes_str1 = strings.Join(strings.Fields(bytes_str1), "")

	bytes_str2 := fmt.Sprintf("%x", bytes_s2)
	bytes_str2 = strings.Join(strings.Fields(bytes_str2), "")

	bin_str1 := ""
	bin_str2 := ""

	for _, char := range bytes_str1 {
		bin_str1 += hexToBinary(fmt.Sprintf("%c", char))
	}
	for _, char := range bytes_str2 {
		bin_str2 += hexToBinary(fmt.Sprintf("%c", char))
	}
	distance := 0

	for i := 0; i < len(bin_str1); i++ {
		if bin_str1[i] != bin_str2[i] {
			distance++
		}
	}
	return distance
}