题解 | #整数与IP地址间的转换#

class HelloWorld {
    public static void main(String[] args) {
       Scanner in = new Scanner(System.in);
        String s = in.nextLine();
        String num = in.nextLine();

        String[] sp = s.split("\\.");
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < sp.length; i++) {
            String s1 = Integer.toBinaryString(Integer.parseInt(sp[i]));
            if (s1.length() == 8) {
                sb.append(s1);
            } else {
                int k = 8 - s1.length();
                while (k-- > 0) {
                    sb.append('0');
                }
                sb.append(s1);
            }

        }
        String str = sb.toString();
        int j = str.length();
        long sum = 0;
        int a = 0;
        while (j-- > 0) {
            int i = str.charAt(j) - '0';
            sum = (long) (Math.pow(2, a++) * i + sum);
        }
        System.out.println(sum);



        String s1 = Long.toBinaryString(Long.parseLong(num));
        StringBuilder sb2 = new StringBuilder();

        if (s1.length() < 32) {
            int k = 32 - s1.length();
            while (k-- > 0) {
                sb2.append('0');
            }
            sb2.append(s1);
            s1 = sb2.toString();
        }

        StringBuilder sb3 = new StringBuilder();
        for (int i = 0; i < 32; i = i + 8) {
            String sub = s1.substring(i, i + 8);
            j =8;
            sum = 0;
            a = 0;
            while (j-- > 0) {
                int i1 = sub.charAt(j)-'0';
                sum = (int) (Math.pow(2, a++) * i1 + sum);
            }
            sb3.append(sum).append('.');

        }
        System.out.println(sb3.toString().substring(0,sb3.length()-1));
    }
}