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public static void main(String[] args) throws IOException {

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));


        PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));

        String str = br.readLine();
        long n =Long.parseLong(str.trim());

        int count = 0;
        while (n > 0) {
            count += n & 1;
            n = n >> 1;
        }
        out.println(count);

        out.flush();
        out.close();
        br.close();
    }