public void cCalc() {

    oct1 = oct1 & sm1;
    oct2 = oct2 & sm2;
    oct3 = oct3 & sm3;
    oct4 = oct4 & sm4;

    String binString;
    binString = Integer.toBinaryString(sm1) + Integer.toBinaryString(sm2) +
            Integer.toBinaryString(sm3) + Integer.toBinaryString(sm4);

    int count = 0;
    for (int loop = 0; loop < binString.length(); loop++) {
        if (binString.charAt(loop) == '1') {
            count++;
        }
    }

    int hostBits = 32 - count;
    int hostsAvailable = (int) Math.pow(2, hostBits) - 2; //2^n - 2

    int extraBits = count - 24;
    int networksAvailable = (int) Math.pow(2, extraBits);

    System.out.println("Hosts per Network = " + hostsAvailable);
    System.out.println("Number of Networks = " + networksAvailable);

    String finalCalc = "";

    for (int loop = 1; loop <= networksAvailable; loop++) {
        //ID
        finalCalc = finalCalc + " Network ID: " + oct1 + "." + oct2 + "." + oct3 + "." + oct4;

        //Start
        oct4 = oct4 + 1;
        finalCalc = finalCalc + "\n Subnet Range(s): " + oct1 + "." + oct2 + "." + oct3 + "." + oct4 + " to ";

        //End
        oct4 = oct4 + hostsAvailable - 1;
        finalCalc = finalCalc + " " + oct1 + "." + oct2 + "." + oct3 + "." + oct4;

        //BroadcastAddress
        oct4 = oct4 + 1;
        finalCalc = finalCalc + "\n Broadcast address: " + oct1 + "." + oct2 + "." + oct3 + "." + oct4;

        //For next ID
        oct4 = oct4 + 1;

        finalCalc = finalCalc + "\n";

        setResult(finalCalc);

    }
}

这是我在子网范围计算器应用程序中的c类ip地址范围计算方法-虽然我了解c类所需的计算，但a类和b类的计算对我来说似乎是不可能的。
我怎么开始计算a和b级呢？在过去一周左右的时间里，我一直在用谷歌搜索和反复试验，但我似乎无法理解这一点。
任何建议或信息都会非常棒。
（请原谅我的代码可能不好，我是java的初学者）