BV024bitOpIPAddrExample

#include <iostream>

int main()
{
    // 0xffff
    // hex system 0..9, a - 10 b - 11 c -12 d -13 e -14 f -15
    // ff -> f * 16 ^ 0 + f * 16 ^ 1 = 15 + 240 = 255
    //uint8_t byte{0x1a}; // 16^0 * a + 16^1 * 1 = 1 * 10 + 16 * 1 = 10 + 16 = 26
    //uint8_t byte{ 0b1111 }; // (1 * 2 ^ 0) + (1 * 2 ^ 1) + (1 * 2 ^ 2) + (1 * 2 ^ 3) = 1 * 1 + 1 * 2 + 1 * 4 + 1 * 8 = 15

    // ~ - bitwise NOT - unary op
    // << - bitwise shift left - binary op
    // >> - bitwise shift right - binary op
    // | - bitwise OR - binary op
    // & - bitwise AND - binary op
    // ^ - bitwise XOR - binary op

    // <<= a = a << 1 -> a <<= 1
    // >>= a = a >> 4 -> a >>= 4
    // |= a = a | b -> a |= b
    // &= a = a & 0b0101 -> a &= 0b0101
    // ^= a = a ^ 42 -> a ^= 42

    // /4
    uint8_t ip1{ 0b01100111 };
    uint8_t ip2{ 0b01101101 };
    uint8_t ip3{ 0b10100111 };
    uint8_t ip4{ 0b01101110 };

    uint8_t mask{ 0b11110000 };
    uint8_t maskLength{0};

    bool sameNet{ false };
    sameNet = ((ip1 & mask) == (ip3 & mask));

    std::cout << std::boolalpha << sameNet << '\n';

    //for (uint8_t invMask{ (uint8_t)~mask }; (invMask >>= 1); --maskLength);
    for (uint8_t maskSh{ mask }; maskSh; maskSh <<= 1, ++maskLength);

    /*for (uint8_t maskSh{ mask }; maskSh; maskSh <<= 1)
    {
        ++maskLength;
    }

    {
        uint8_t maskSh{ mask };
        while (maskSh != 0)
        {
            maskSh <<= 1;
            ++maskLength;
        }
    }*/


    std::cout << "maskLength = " << +maskLength << '\n';

    //ip1   0b01100111
    //mask  0b11110000

    //ip1   0b01100111
    //~mask 0b00001111
    //      0b00000111

    uint8_t host{0};
    uint8_t net{0};


    net = ip1 >> maskLength;
    host = ip1 & (~mask);

    std::cout << "ip1 = " << +ip1 << " net = " << +net << " host = " << +host <<'\n';

    net = ip2 >> maskLength;
    host = ip2 & (~mask);

    std::cout << "ip2 = " << +ip2 << " net = " << +net << " host = " << +host << '\n';

    net = ip3 >> maskLength;
    host = ip3 & (~mask);

    std::cout << "ip3 = " << +ip3 << " net = " << +net << " host = " << +host << '\n';

    net = ip4 >> maskLength;
    host = ip4 & (~mask);

    std::cout << "ip4 = " << +ip4 << " net = " << +net << " host = " << +host << '\n';

    return 0;
}