public static void FL(int []a, int k) {
		boolean flag=false;
		int x=-1, y=-1;
		for (int i = 0; i < a.length; i++) {
			int ans = a[i] ^ k;
			if (ans == 0) {
				if(!flag){
					flag=true;
					x=i;
				}
				y=i;
			}

		}
		System.out.println(x+" "+y);


	}