20220602 Mathematics: Excel table column serial number

         Title Description ： Give you a string columnTitle , Express Excel Column names in the table . return The column sequence number corresponding to the column name .

         coded ：

    public int titleToNumber(String columnTitle) {
        Long result=0L;
        if (null == columnTitle){
            return result.intValue();
        }
        char[] chars = columnTitle.toCharArray();
        for(int i=0;i<chars.length;i++)
        {
            result = (result+chars[i]-'A'+1) * 26;
        }
        result = result / 26;
        return result.intValue();
    }