Create arrays from randomly placed letters in Java

Question

How can I create an 80-character string array with the letters a, b, and c? Each time, the places of these letters a, b and c need to be arranged randomly. For example abcbabcabcababbc ... abcba

 String[] str = new String[80];

see https://stackoverflow.com/questions/41107/how-to-generate-a-random-alpha-numeric-string for different approaches to creating a string with random characters — Sebastian Richner, Jan 09 '21 at 14:32
Loop over the array positions, get a random number 0-2, then put the appropriate character in that index — OneCricketeer, Jan 09 '21 at 14:41

score 1 · Accepted Answer · answered Jan 09 '21 at 15:02

You could use the Ascii values. Lower case letters start with 97 (a).

public static void main(String[] args) {
    Random r = new Random();
    String[] s = new String[80];
    for (int i = 0; i < 80; ++i) {
        s[i] = "" + ((char) (r.nextInt(3) + 97));
    }

    Arrays.stream(s).forEach(System.out::print);
}

Alternative solution:

public static void main(String[] args) {
    Random r = new Random();
    String[] letters = {"a", "b", "c"};
    String[] s = new String[80];
    for (int i = 0; i < 80; ++i) {
        s[i] = letters[r.nextInt(letters.length)];
    }

    Arrays.stream(s).forEach(System.out::print);
}

Create arrays from randomly placed letters in Java

1 Answers1