Method scramble

app/src/main/java/solver/HalfTurn.java:100–126

(Random r)

    }

    public static String scramble(Random r) {
        int cp1, cp2;
        do {
            cp1 = r.nextInt(24);
            cp2 = r.nextInt(24);
        } while (cpd[cp1 * 24 + cp2] < 0);
        int ep1, ep2, ep3;
        do {
            ep1 = r.nextInt(24);
            ep2 = r.nextInt(24);
            ep3 = r.nextInt(24);
        } while (epd[ep1][ep2][ep3] < 0);
        for (int d = 0; d < 20; d++) {
            if (search(cp1, cp2, ep1, ep2, ep3, d, -1)) {
                if (d < 2) return scramble(r);
                if (d < 4) {
                    continue;
                }
                StringBuilder sb = new StringBuilder();
                for (int i = 1; i <= d; i++) {
                    sb.append(turn[seq[i]]).append("2 ");
                }
                return sb.toString();
            }
        }
        return "error";
    }
}