#include <iostream>
#include <string>
#include <iomanip>
#include <typeinfo>
using namespace std;

int main() {
  string num1, num2;
  string num3;
  bool flag1(false), flag2(false);
  int choose, carry = 0;

  while (flag1 == false || flag2 == false) {
    if (flag1 == false) {
      cout << "Please enter number one! \n";
      cin >> num1;
      for (int i = 0; i < num1.length(); i++) {
        if (!(num1[i] == '0' || num1[i] == '1'))
        {
          cout << "  Binary1     is     not     valid.  \n";
          flag1 = false;
          break;
        }
        else {
          flag1 = true;
        }
      }
    }
    if (flag2 == false && flag1 != false) {
      cout << "Please enter number two! \n";
      cin >> num2;
      for (int i = 0; i < num2.length(); i++)
      {
        if (!(num2[i] == '0' || num2[i] == '1'))
        {
          cout << "  Binary2     is     not     valid.  \n";
          flag2 = false;
          break;
        }
        else {
          flag2 = true;
        }
      }
    }
  }



int size = num1.length() > num2.length() ? num1.length()-1 : num2.length()-1;

  if (num1.length() > num2.length())
  {
    num2.insert(0, num1.length()-num2.length(), '0');
  }
  else
  {
    num1.insert(0, num2.length()-num1.length(), '0');
  }
  cout << num1 << " " << num2 << endl;

int* sum=new int[num2.length()];

  cout << "1.Sum Or 2.Minus : ";
  cin >> choose;
  // cout << typeid(choose).name() << endl;
if (choose == 1) {
    for (int i = num1.length()-1; i >= 0; i--) {
        sum[i] = num1[i] ^ num2[i] ^ carry;
        carry = (num1[i] && num2[i]) || (carry && (num1[i] ^ num2[i]));
    }
    cout << carry;
    for (int i = 0;i <= num1.length()-1;i++) {
        cout << sum[i];
    }
    cout << endl;
}

if (choose == 2) {
    bool flag(false);
    carry = 0;
    for (int i = size; i >= 0; i--) {
        if (flag == true) {
            if (num2[i] == '0') {
                num2[i] = '1';
            } else {
                num2[i] = '0';
            }
        }
        if (num2[i] == '1') {
            flag = true;
        }
    }
    cout << "num2" << num2 << endl;
    for (int i = size; i >= 0; i--) {
        sum[i] = num1[i] ^ num2[i] ^ carry;
        carry = (num1[i] && num2[i]) || (carry && (num1[i] ^ num2[i]));
    }
    cout << carry;
    for (int i = 0;i <= size;i++) {
        cout << sum[i];
    }
    cout << endl;
}
  return 0;
}