Java base转换程序给定值、它的base和new base

Question

我正在尝试弄清楚如何将特定基数中的任何值转换为不同基数中的相应表示。您将获得一个值、它的基数以及在.dat文件的每一行中值需要转换为的基数。

.dat文件中3行的示例，其中行中的第一个数字是值，然后是它所在的基数，然后是它需要转换为的基数：

10 10 2

AB 16 10

345 6 4

我相信我已经弄明白了，除了如何计算16和18等基数的字母值。请帮助：

public static void main( String args[] ) throws IOException
    {
        Scanner file = new Scanner(new File("baseConversion.dat"));
        //Keep looping while you can still read lines from the file
        while (file.hasNextLine())
        {
            //Read a line from the file -- read it as a string
            String line = file.nextLine();

            int firstSpace = line.indexOf(" ");
            int lastSpace = line.lastIndexOf(' ', line.length());
            String oldBase = line.substring(firstSpace + 1, lastSpace); 


            // Get the new base from the string
            int newBase = Integer.parseInt(line.substring(lastSpace + 1));


            //  Convert from the Old base to base 10
            int numberInBase10 = convertToTen(line.substring(0, firstSpace), Integer.parseInt(oldBase));
            System.out.println("Converted " + line.substring(0, firstSpace) + " from base " + oldBase + " to " +
            numberInBase10 + " in base 10\n");

            public static String convert(int numberInBase10, int base)
            {
            int quotient = numberInBase10 / newBase;
            int remainder = numberInBase10 % newBase;

            if(quotient == 0)
            {
                return Integer.toString(remainder);      
            }
            else
            {
                return convert(quotient, newBase) + Integer.toString(remainder);
            }
        }

        // DO THIS Print out results


        }
        file.close();
    }


    static int convertToTen(String num, int base)
    {

    int leng = num.length();
    int base10 = 0;
    int remainder = 0;
    int add = 0;


        for(int i = leng-1; i >=0; i--)
        {
            int intValueForC = 0;
            remainder = 0;

            char c = num.charAt(leng-i-1);
            if(!Character.isDigit(c))
            {
                intValueForC = c - 55;
            }
            else
            {
                intValueForC = c - 48;
            }
            add +=(intValueForC * Math.pow(base, i));

        }

        return add;
    }
}

Answer 1

你把这件事变得过于复杂了(除非这是家庭作业，而且你不允许使用库函数)。

String hex = "ABCDEF";
int decimal = Integer.parseInt(hex, 16);
String binary = Integer.toString(decimal, 2);