converting a string array with letters into an int array in java

Question

Ok im going to try and explain my problem here and what I need to do is convert a string array into an int array.

Here is part of what I have (well the initial set up)

   System.out.println("Please enter a 4 digit number to be converted to decimal ");
    basenumber = input.next();

    temp = basenumber.split("");
    for(int i = 0; i < temp.length; i++)
        System.out.println(temp[i]);

    //int[] numValue = new int[temp.length];
    ArrayList<Integer>numValue = new ArrayList<Integer>();

    for(int i = 0; i < temp.length; i++)
        if (temp[i].equals('0')) 
            numValue.add(0);
        else if (temp[i].equals('1')) 
            numValue.add(1);
                     ........
        else if (temp[i].equals('a') || temp[i].equals('A'))
            numValue.add(10);
                     .........
             for(int i = 0; i < numValue.size(); i++)
        System.out.print(numValue.get(i));

Basically what I am trying to do it set 0-9 as the actual numbers and then proceed to have a-z as 10-35 from the input string such as Z3A7 ideally would print as 35 3 10 7

Answer 1

Try this in your loop:

Integer.parseInt(letter, 36);

This will interpret letter as a base36 number (0-9 + 26 letters).

Integer.parseInt("2", 36); // 2
Integer.parseInt("B", 36); // 11
Integer.parseInt("z", 36); // 35

Answer 2

You can use this single line in the loop (assuming user doesn't enter empty string):

int x = Character.isDigit(temp[i].charAt(0)) ?
        Integer.parseInt(temp[i]) : ((int) temp[i].toLowerCase().charAt(0)-87) ;

numValue.add( x );

Explanation of the code above:

• temp[i].toLowerCase() => z and Z will convert to the same value.
• (int) temp[i].toLowerCase().charAt(0) => ASCII code of character.
• -87 => Substracting 87 for your specification.

Answer 3

Considering that you want to denote Z as 35, I have written the following function

UPDATE :

The ASCII value for Z is 90, so if you want to denote Z as 35 then you should subtract every character from 55 as (90-35=55):

public static int[] convertStringArraytoIntArray(String[] sarray) throws Exception {
    if (sarray != null) {
        int intarray[] = new int[sarray.length];
        for (int i = 0; i < sarray.length; i++) {
            if (sarray[i].matches("[a-zA-Z]")) {
                intarray[i] = (int) sarray[i].toUpperCase().charAt(0) - 55;
            } else {
                intarray[i] = Integer.parseInt(sarray[i]);
            }
        }
        return intarray;
    }
    return null;
}