Excel Sheet Column Number

ExcelSheetColumnNumber.go

func titleToNumber(s string) int {
    sum := 0
    l := len(s) -1
    for i :=len(s)-1; i>=0;  i-- {
        sum += int((s[i]-64)) * int(math.Pow(float64(26), float64(l-i) ))
    }
    return sum 
}

//-----------------------------------------------------------------
func titleToNumber(s string) int {
	bytes := []byte(s)
	var ret int
	for i := range bytes {
		ret = 26 * ret + int(bytes[i] - 'A' + 1)
     }
	return ret
}