Splitting a String by the numbers in between

Question

I'm trying to split a String at the numbers. For example if I have

String x = 2A2B;

I want to be able to be able to split the String into parts and then print out "AABB" to the screen. Can anyone help me with that?

Answer 1

Below code snippet may help you

    String str = "3A2B";
    // split the string on
    String st[] = str.split("(?<=\\D)(?=\\d)");
    System.out.println(Arrays.toString(st));
    for (String s : st) {
        String intValue = s.substring(0, s.length()-1);
        int i = Integer.parseInt(intValue);
        char c = s.charAt(s.length()-1);
        while (i > 0) {
            System.out.print(c);
            i--;
        }
        System.out.println();

    }

Answer 2

Try using a java.util.Scanner

Scanner.nextInt()
Scanner.next()

They will help you with your task.

Answer 3

It can server your basic purpose:

String x = "2A2B";
int times = 0;
for(char ch:x.toCharArray()){
    if(Character.isDigit(ch)){
        times = times*10+(Integer.valueOf(String.valueOf(ch)));
    }else{
        do{
            System.out.print(ch);
            times--;
        }while(times > 0);
        times = 0;
    }
}

Answer 4

I would suggest using scanners + delimiters for this.

Scanner s = new Scanner(input).useDelimiter("\d");

Will read the string, splitting it by digits (\\d), and next() should first give "A", then "B"

Scanner s = new Scanner(input).useDelimiter("\D");

Will read the string, splitting by anything that's not a digit, next() should return "2", then "2"

Something like this maybe? (assuming there's always one number followed by one letter)

String rawSequence = "2U2D1L1R1L1R1B1A";
string newSequence = "";

Scanner scanLetters = new Scanner(rawSequence);
scanLetters.useDelimiter("\d");
Scanner scanNumbers = new Scanner(rawSequence);
scanLetter.useDelimeter("\D");

String[] letters = new String[ rawSequence.length()/2 ];
int[] amounts = new int[ rawSequence.length()/2 ];

for (int x = 0; x < rawSequence.length(); x++){
    letters[x] = scanLetters.next()
    numbers[x] = scanNumbers.next()
}

for (int i = 0, i < amounts.length, i++){
    for (int j = 0; j < amounts[i], j++){
        newSequence.concat(letters[i]);
    }
}