public class XORPatternFinder {
    private static final byte[] constantArray = {
        (byte) 0x1F, (byte) 0xF9, (byte) 0xF5, (byte) 0x99, (byte) 0xAC, (byte) 0x9B, (byte) 0x58, (byte) 0x7B,
        (byte) 0x9F, (byte) 0x65, (byte) 0xE0, (byte) 0x7D, (byte) 0xAA, (byte) 0x3F, (byte) 0xCD, (byte) 0xB9,
        (byte) 0x49, (byte) 0xD7, (byte) 0xB2, (byte) 0xCE, (byte) 0xAA, (byte) 0x8F, (byte) 0x0C, (byte) 0x75,
        (byte) 0x81, (byte) 0x73, (byte) 0xB5, (byte) 0x51, (byte) 0xF3, (byte) 0x6E, (byte) 0x98, (byte) 0x80,
        (byte) 0x52, (byte) 0x82, (byte) 0xE2, (byte) 0x8D, (byte) 0xAB, (byte) 0xB3, (byte) 0x4D, (byte) 0x66,
        (byte) 0x99, (byte) 0x7C, (byte) 0xB6, (byte) 0x7C, (byte) 0xFA, (byte) 0x6F, (byte) 0x83, (byte) 0xBC,
        (byte) 0x4D, (byte) 0xCB, (byte) 0xD5
    };
    public static void main(String[] args) {
        findValidCandidates();
    }
    private static void findValidCandidates() {
        System.out.println("Valid candidates for Array1:");
        for (int pos = 0; pos < 8; pos++) {
            System.out.printf("\nPosition %d (XORs with indices %s):\n", pos,
                            getAffectedIndices(pos));
            findCandidatesForPosition(pos);
        }
        System.out.println("\nValid candidates for Array2:");
        for (int pos = 0; pos < 8; pos++) {
            System.out.printf("\nPosition %d (XORs with indices %s):\n", pos,
                            getAffectedIndices(pos + 8));
            findCandidatesForPosition(pos + 8);
        }
    }
    private static void findCandidatesForPosition(int pos) {
        StringBuilder validBytes = new StringBuilder();
        StringBuilder resultingChars = new StringBuilder();

        for (int b = 0; b < 256; b++) {
            byte candidate = (byte) b;
            if (isValidByte(candidate, pos)) {
                if (validBytes.length() > 0) {
                    validBytes.append(", ");
                    resultingChars.append(", ");
                }
                validBytes.append(String.format("0x%02X", candidate));
                resultingChars.append(getResultingChars(candidate, pos));
            }
        }

        System.out.println("Bytes: " + validBytes);
        System.out.println("Chars: " + resultingChars);
    }
    private static String getResultingChars(byte candidate, int startPos) {
        StringBuilder chars = new StringBuilder();
        for (int i = startPos; i < constantArray.length; i += 16) {
            chars.append((char)(constantArray[i] ^ candidate));
        }
        return chars.toString();
    }
    private static String getAffectedIndices(int startPos) {
        StringBuilder indices = new StringBuilder();
        for (int i = startPos; i < constantArray.length; i += 16) {
            if (indices.length() > 0) indices.append(", ");
            indices.append(i);
        }
        return indices.toString();
    }
    private static boolean isValidByte(byte candidate, int startPos) {
        for (int i = startPos; i < constantArray.length; i += 16) {
            int result = constantArray[i] ^ candidate;
            if (!isAllowedChar((char)result)) {
                return false;
            }
        }
        return true;
    }
    private static boolean isAllowedChar(char c) {
        return (c >= 'A' && c <= 'Z') ||
               (c >= 'a' && c <= 'z') ||
               (c >= '0' && c <= '9') ||
               c == '{' || c == '}';
    }
}