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public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StreamTokenizer in = new StreamTokenizer(br);
        PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));

        in.nextToken();
        int n = (int)in.nval;

        out.println(find(n));
        out.flush();
        out.close();
        br.close();
    }

    private static int find(int n) {

        int n2 = 0, n5 = 0;
        int p = 1;

        for(int i=2;i<=n;i++){
            int tmp = i;
            while (tmp%5==0) {
                n5++;
                tmp/=5;
            }

            while (tmp%2==0) {
                n2++;
                tmp/=2;
            }

            p=(p*tmp)%10;
        }

        for(int i=0;i<n2-n5;i++){
            p=(p*2)%10;
        }
        return p;
    }