My code is having only one for loop, still I'm getting time out for test cases:8,9,10. Can anyone help me out?

        Scanner in = new Scanner(System.in);
        Deque deque = new ArrayDeque<>();
        int n = in.nextInt();
        int m = in.nextInt();
        int count=0;
        int ans=0;
        for (int i =0; i < n; i++) {
            int num=in.nextInt();
            if(deque.contains(num))
                count=deque.size();
            else{
                count=deque.size()+1;
                deque.addLast(num);
                if(i>=m-1)
                    deque.pollFirst();
            }
            if(count>ans)
                ans=count;
        }
        System.out.println(ans);