import java.util.Arrays;
import java.util.Random;
 
class ShuffleIndicies {
	public static void main (String[] args) {
		int[] indicies = range(52);
		print("Before:", indicies);
		shuffleArray(indicies);
		print("After:", indicies);
	}
 
	// Fisher–Yates shuffle
	public static void shuffleArray(int[] ar) {
		Random r = new Random();
		for (int i = ar.length - 1; i > 0; i--) {
			int index = r.nextInt(i + 1);
			int t = ar[index];
			ar[index] = ar[i];
			ar[i] = t;
		}
	}
 
	public static final int[] range(int length) {
		return range(0, length);
	}
 
	public static final int[] range(int start, int length) {
		int[] range = new int[length - start + 1];
		for (int i = start; i <= length; i++) {
			range[i - start] = i;
		}
		return range;
	}
 
	public static void print(String label, int[] arr) {
		System.out.printf("%s\n%s\n", label, Arrays.toString(arr));
	}
}

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