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#define NUM_BITS 8

#include <iostream>


struct Number{
    int num : NUM_BITS;
    Number(){}
    Number(const int& bruh){
        num = bruh;
    }
    operator int() const { return num; }
    Number& operator=(const int& bruh){
        num = bruh;
        return (*this);
    }
};

using namespace std;

bool isNegative(const int& num){
    //This gets the bitwise and of num and 10000000000000000000000000000000
    //This implicit casts to bool, which means (num & (1 << 31)) != 0
    return (num & (1 << 31));
}

void printBinaryNumber(const int& num, const int numBits){
    for(int i = numBits; i > 0; --i){
        //8..1
        int bitMask = 1 << (i-1);
        if(num & bitMask){ //Test the bit
            cout << '1';
        }else{
            cout << '0';
        }
    }
}

void printCarryBits(const int& a, const int& b, const int numBits){
    int answer = 0;
    
    bool carry = false;
    for(int i = 0; i < numBits; ++i){
        //8..1
        int bitMask = 1 << i;
        bool aBit = a & bitMask;
        bool bBit = b & bitMask;
        if(aBit && bBit || aBit && carry || bBit && carry){ //Carry bit is true next
            if(carry)
                answer |= bitMask;
            carry = true;
        }else{
            if(carry)
                answer |= bitMask;
            carry = false;
        }
    }
    printBinaryNumber(answer, 8);
}


void printBorrowBits(const int& a, const int& b, const int numBits){
    int answer = 0;
    
    bool carry = false;
    for(int i = 0; i < numBits; ++i){
        //8..1
        int bitMask = 1 << i;
        bool aBit = a & bitMask;
        bool bBit = b & bitMask;
        if((!(aBit ^ carry)) && bBit){ //Carry bit is true next
            if(carry)
                answer |= bitMask;
            carry = true;
        }else{
            if(carry)
                answer |= bitMask;
            carry = false;
        }
    }
    printBinaryNumber(answer, 8);
}

void doProblem(const int& a, const int& b, const char& sign, const int& result, const int& numBits){
    if(sign == '+'){
        cout << ' '; printCarryBits(a, b, numBits); cout << endl;
    }else{
        cout << ' '; printBorrowBits(a, b, numBits); cout << endl;
    }
    cout << ' '; printBinaryNumber(a, numBits); cout << endl;
    cout << sign; printBinaryNumber(b, numBits); cout << endl;
    cout << "----------" << endl;
    cout << ""; printBinaryNumber(result, numBits + 1); cout << " = " << result;
    cout << endl;
}

int main(){
    
    Number a = 0b110;
    Number b = 0b011;
    cout<< a << endl << b << endl;
    
    doProblem(a, b, '+', a + b, NUM_BITS);
    doProblem(a, b, '-', a - b, NUM_BITS);
    doProblem(-a, b, '+', -a + b, NUM_BITS);
    doProblem(a, b, '-', -a - b, NUM_BITS);
    

    return 0;
}
//===============Header File==================
#include <iostream>
#include <sstream> //stringbuf
#include <utility> //exchange

//Couple rules:
//Characters given through the getter functions have to be removed from the buffer.
    //This is so that bufferEmpty() == buffer.in_avail() > 0 basically always.
    //skipWhitespace doesn't remove the text from the buffer, but it does return the number of characters.
//nextWord will trim whitespace before the word
//nextInt will trim non-numbers before the number
//hasNextInt and hasNextWord will trim the whitespace. If you think you need it, you should get nextWhitespace before doing any of those.
//Whitespace after a word or an int is left on the buffer.
//nextWhitespace will (get and) remove whitespace until the end of the line, including the newline character, but stops before the next line.
    //nextWhitespace won't read the next line when called before the end of the line, and it won't prompt the user for the next line if interactive.
        //If nextWhitespace is called after reading the end of the line, then it will read a new line into the buffer, which will prompt the user.
    //It acts like nextLine, but if there's something non-whitespace on the current line it stops there.
class Scanner {
    public:
        std::stringbuf buffer;
        std::istream& input;
        
        Scanner(std::istream& in = std::cin) : buffer(), input(in) {}
        
    //Buffer debugging
        bool fillBuffer();
    
        bool bufferEmpty();
        void printBufferEmpty();
        std::string getBuffer();
        size_t bufferLength();
        void printBufferStats();
    
    //Int
        bool hasNextInt();
        int nextInt();
    
    //Word
        bool hasNextWord();
        std::string nextWord();
    
    //Line
        bool hasNextLine();
    
    //Whitespace
        size_t skipWhitespace();    //Prob should be private, but I don't believe in that private shit.
        bool hasNextWhitespace();
        std::string nextWhitespace();
        std::string nextWhitespaceAll();
        std::string nextLine();
};

//===============Source File==================
bool Scanner::fillBuffer() {    //Returns if it had to get the next line from the input.
    const bool badInput = input.eof() || input.bad();
    const bool shouldFillBuffer = bufferEmpty() && !badInput;
    if (shouldFillBuffer) {
        std::string line;
        if (std::getline(input, line)) {
            buffer.str(buffer.str() + line + "\n");
        }
    }
    return shouldFillBuffer;
}

bool Scanner::bufferEmpty(){
    return buffer.str() == "";
}
void Scanner::printBufferEmpty(){
    std::cout << "The buffer is " << (bufferEmpty()? "" : "not") << " empty." << std::endl;
}

std::string Scanner::getBuffer(){
    return buffer.str();
}
size_t Scanner::bufferLength(){
    return buffer.str().length();
}
void Scanner::printBufferStats(){
    if(bufferEmpty()){
        std::cout << "The buffer is \"\"" << std::endl;
        return;
    }
    std::cout << "The length of the buffer is " << bufferLength() << std::endl;
    if(buffer.sgetc() == '\r'){
        std::cout << "The buffer is \\r\\n" << std::endl;
    }else if(buffer.sgetc() == '\n'){
        std::cout << "The buffer is \\n" << std::endl;
    }
}

bool Scanner::hasNextInt() {
    return hasNextWord() && (std::isdigit(buffer.sgetc()) || buffer.sgetc() == '-');
}

int Scanner::nextInt() {
    if (!hasNextInt()) {   //Will fill the buffer if not filled. Will also trim whitespace.
        return 0;
    }
    
    std::string num;
    size_t charactersRead = 0;
    while (buffer.in_avail() > 0 && (std::isdigit(buffer.sgetc()) || buffer.sgetc() == '-')) {
        num += buffer.sbumpc();
        ++charactersRead;
    }
    buffer.str(buffer.str().erase(0, charactersRead));
    return std::stoi(num);
}

bool Scanner::hasNextWord() {
    nextWhitespaceAll();
    return buffer.in_avail() > 0;
}

std::string Scanner::nextWord() {
    if (!hasNextWord()) {   //Will fill the buffer if not filled. Will also trim whitespace.
        return "";
    }
    
    std::string word;
    size_t charactersRead = 0;
    while (buffer.in_avail() > 0 && !std::isspace(buffer.sgetc())) {
        word += buffer.sbumpc();
        ++charactersRead;
    }
    buffer.str(buffer.str().erase(0, charactersRead));
    return word;
}

bool Scanner::hasNextLine() {
    return (!bufferEmpty()) || fillBuffer();
}

size_t Scanner::skipWhitespace() {   //Returns characters read
    size_t charactersRead = 0;
    while (buffer.in_avail() > 0 && std::isspace(buffer.sgetc())) {
        buffer.sbumpc();
        ++charactersRead;
    }
    return charactersRead;
}
bool Scanner::hasNextWhitespace(){
    fillBuffer();
    return buffer.in_avail() > 0 && std::isspace(buffer.sgetc());
}
std::string Scanner::nextWhitespace() {
    if (!hasNextWhitespace()) {   //Will fill the buffer if not filled
        return "";
    }
    const size_t charactersRead = skipWhitespace();
    std::string whitespace = buffer.str().substr(charactersRead);
    buffer.str(buffer.str().erase(0, charactersRead));
    return whitespace;
}
std::string Scanner::nextWhitespaceAll(){
    std::string whitespace;
    while(hasNextWhitespace()){
        std::string gottenWhiteSpace = nextWhitespace();
        whitespace += gottenWhiteSpace;
    }
    return whitespace;
}
std::string Scanner::nextLine(){
    if (!hasNextLine()) {
        return "";
    }
    
    fillBuffer();
    //Swap out the old buffer with an empty buffer, and get the old buffer as a variable.
    std::string line = std::exchange(buffer, std::stringbuf()).str();
    
    //Remove the newline.
    if(line[line.length() - 1] == '\n' || line[line.length() - 1] == '\r' ) line.pop_back();
    if(line[line.length() - 1] == '\r' || line[line.length() - 1] == '\n' ) line.pop_back();
    return line;
}


//=================Word and Int test=================
while(bruh.hasNextInt() || bruh.hasNextWord()){
    std::cout << "started loop" << std::endl;
    if(bruh.hasNextInt()){
        std::cout << "Int: " << bruh.nextInt() << " " << std::endl;
    }else{
        std::cout << "Word: " << bruh.nextWord() << " " << std::endl;
    }
    bruh.nextWhitespace();
}
//===================Line test======================
for(int count = 1; bruh.hasNextLine(); ++count){
    std::string line = bruh.nextLine();
    std::cout << "Line " << count << ": " << line << std::endl;
}